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Scientific consensus: Earth's climate is warming
Multiple studies published in peer-reviewed scientific journals1 show that 97 percent or more of actively publishing climate scientists agree*: Climate-warming trends over the past century are extremely likely due to human activities.
American Association for the Advancement of Science
"The scientific evidence is clear: global climate change caused by human activities is occurring now, and it is a growing threat to society." (2006)
American Chemical Society
"Comprehensive scientific assessments of our current and potential future climates clearly indicate that climate change is real, largely attributable to emissions from human activities, and potentially a very serious problem." (2004)
American Geophysical Union
"Human‐induced climate change requires urgent action. Humanity is the major influence on the global climate change observed over the past 50 years. Rapid societal responses can significantly lessen negative outcomes." (Adopted 2003, revised and reaffirmed 2007, 2012, 2013)
American Medical Association
"Our AMA ... supports the findings of the Intergovernmental Panel on Climate Change’s fourth assessment report and concurs with the scientific consensus that the Earth is undergoing adverse global climate change and that anthropogenic contributions are significant." (2013)
American Meteorological Society
"It is clear from extensive scientific evidence that the dominant cause of the rapid change in climate of the past half century is human-induced increases in the amount of atmospheric greenhouse gases, including carbon dioxide (CO2), chlorofluorocarbons, methane, and nitrous oxide." (2012)
American Physical Society
"The evidence is incontrovertible: Global warming is occurring. If no mitigating actions are taken, significant disruptions in the Earth’s physical and ecological systems, social systems, security and human health are likely to occur. We must reduce emissions of greenhouse gases beginning now." (2007)
The Geological Society of America
"The Geological Society of America (GSA) concurs with assessments by the National Academies of Science (2005), the National Research Council (2006), and the Intergovernmental Panel on Climate Change (IPCC, 2007) that global climate has warmed and that human activities (mainly greenhouse‐gas emissions) account for most of the warming since the middle 1900s." (2006; revised 2010)
U.S. Global Change Research Program
"The global warming of the past 50 years is due primarily to human-induced increases in heat-trapping gases. Human 'fingerprints' also have been identified in many other aspects of the climate system, including changes in ocean heat content, precipitation, atmospheric moisture, and Arctic sea ice." (2009)
Intergovernmental Panel on Climate Change
“Warming of the climate system is unequivocal, and since the 1950s, many of the observed changes are unprecedented over decades to millennia. The atmosphere and ocean have warmed, the amounts of snow and ice have diminished, and sea level has risen.”
“Human influence on the climate system is clear, and recent anthropogenic emissions of greenhouse gases are the highest in history. Recent climate changes have had widespread impacts on human and natural systems.”
List of worldwide scientific organizations
The following page lists the nearly 200 worldwide scientific organizations that hold the position that climate change has been caused by human action.
Academia Chilena de Ciencias, Chile
Academia das Ciencias de Lisboa, Portugal
Academia de Ciencias de la República Dominicana
Academia de Ciencias Físicas, Matemáticas y Naturales de Venezuela
Academia de Ciencias Medicas, Fisicas y Naturales de Guatemala
Academia Mexicana de Ciencias,Mexico
Academia Nacional de Ciencias de Bolivia
Academia Nacional de Ciencias del Peru
Académie des Sciences et Techniques du Sénégal
Académie des Sciences, France
Academies of Arts, Humanities and Sciences of Canada
Academy of Athens
Academy of Science of Mozambique
Academy of Science of South Africa
Academy of Sciences for the Developing World (TWAS)
Academy of Sciences Malaysia
Academy of Sciences of Moldova
Academy of Sciences of the Czech Republic
Academy of Sciences of the Islamic Republic of Iran
Academy of Scientific Research and Technology, Egypt
Academy of the Royal Society of New Zealand
Accademia Nazionale dei Lincei, Italy
Africa Centre for Climate and Earth Systems Science
African Academy of Sciences
Albanian Academy of Sciences
Amazon Environmental Research Institute
American Academy of Pediatrics
American Anthropological Association
American Association for the Advancement of Science
American Association of State Climatologists (AASC)
American Association of Wildlife Veterinarians
American Astronomical Society
American Chemical Society
American College of Preventive Medicine
American Fisheries Society
American Geophysical Union
American Institute of Biological Sciences
American Institute of Physics
American Meteorological Society
American Physical Society
American Public Health Association
American Quaternary Association
American Society for Microbiology
American Society of Agronomy
American Society of Civil Engineers
American Society of Plant Biologists
American Statistical Association
Association of Ecosystem Research Centers
Australian Academy of Science
Australian Bureau of Meteorology
Australian Coral Reef Society
Australian Institute of Marine Science
Australian Institute of Physics
Australian Marine Sciences Association
Australian Medical Association
Australian Meteorological and Oceanographic Society
Bangladesh Academy of Sciences
Botanical Society of America
Brazilian Academy of Sciences
British Antarctic Survey
Bulgarian Academy of Sciences
California Academy of Sciences
Cameroon Academy of Sciences
Canadian Association of Physicists
Canadian Foundation for Climate and Atmospheric Sciences
Canadian Geophysical Union
Canadian Meteorological and Oceanographic Society
Canadian Society of Soil Science
Canadian Society of Zoologists
Caribbean Academy of Sciences views
Center for International Forestry Research
Chinese Academy of Sciences
Colombian Academy of Exact, Physical and Natural Sciences
Commonwealth Scientific and Industrial Research Organization (CSIRO) (Australia)
Consultative Group on International Agricultural Research
Croatian Academy of Arts and Sciences
Crop Science Society of America
Cuban Academy of Sciences
Delegation of the Finnish Academies of Science and Letters
Ecological Society of America
Ecological Society of Australia
Environmental Protection Agency
European Academy of Sciences and Arts
European Federation of Geologists
European Geosciences Union
European Physical Society
European Science Foundation
Federation of American Scientists
French Academy of Sciences
Geological Society of America
Geological Society of Australia
Geological Society of London
Georgian Academy of Sciences
German Academy of Natural Scientists Leopoldina
Ghana Academy of Arts and Sciences
Indian National Science Academy
Indonesian Academy of Sciences
Institute of Ecology and Environmental Management
Institute of Marine Engineering, Science and Technology
Institute of Professional Engineers New Zealand
Institution of Mechanical Engineers, UK
InterAcademy Council
International Alliance of Research Universities
International Arctic Science Committee
International Association for Great Lakes Research
International Council for Science
International Council of Academies of Engineering and Technological Sciences
International Research Institute for Climate and Society
International Union for Quaternary Research
International Union of Geodesy and Geophysics
International Union of Pure and Applied Physics
Islamic World Academy of Sciences
Israel Academy of Sciences and Humanities
Kenya National Academy of Sciences
Korean Academy of Science and Technology
Kosovo Academy of Sciences and Arts
l'Académie des Sciences et Techniques du Sénégal
Latin American Academy of Sciences
Latvian Academy of Sciences
Lithuanian Academy of Sciences
Madagascar National Academy of Arts, Letters, and Sciences
Mauritius Academy of Science and Technology
Montenegrin Academy of Sciences and Arts
National Academy of Exact, Physical and Natural Sciences, Argentina
National Academy of Sciences of Armenia
National Academy of Sciences of the Kyrgyz Republic
National Academy of Sciences, Sri Lanka
National Academy of Sciences, United States of America
National Aeronautics and Space Administration
National Association of Geoscience Teachers
National Association of State Foresters
National Center for Atmospheric Research
National Council of Engineers Australia
National Institute of Water & Atmospheric Research, New Zealand
National Oceanic and Atmospheric Administration
National Research Council
National Science Foundation
Natural England
Natural Environment Research Council, UK
Natural Science Collections Alliance
Network of African Science Academies
New York Academy of Sciences
Nicaraguan Academy of Sciences
Nigerian Academy of Sciences
Norwegian Academy of Sciences and Letters
Oklahoma Climatological Survey
Organization of Biological Field Stations
Pakistan Academy of Sciences
Palestine Academy for Science and Technology
Pew Center on Global Climate Change
Polish Academy of Sciences
Romanian Academy
Royal Academies for Science and the Arts of Belgium
Royal Academy of Exact, Physical and Natural Sciences of Spain
Royal Astronomical Society, UK
Royal Danish Academy of Sciences and Letters
Royal Irish Academy
Royal Meteorological Society (UK)
Royal Netherlands Academy of Arts and Sciences
Royal Netherlands Institute for Sea Research
Royal Scientific Society of Jordan
Royal Society of Canada
Royal Society of Chemistry, UK
Royal Society of the United Kingdom
Royal Swedish Academy of Sciences
Russian Academy of Sciences
Science and Technology, Australia
Science Council of Japan
Scientific Committee on Antarctic Research
Scientific Committee on Solar-Terrestrial Physics
Scripps Institution of Oceanography
Serbian Academy of Sciences and Arts
Slovak Academy of Sciences
Slovenian Academy of Sciences and Arts
Society for Ecological Restoration International
Society for Industrial and Applied Mathematics
Society of American Foresters
Society of Biology (UK)
Society of Systematic Biologists
Soil Science Society of America
Sudan Academy of Sciences
Sudanese National Academy of Science
Tanzania Academy of Sciences
The Wildlife Society (international)
Turkish Academy of Sciences
Uganda National Academy of Sciences
Union of German Academies of Sciences and Humanities
United Nations Intergovernmental Panel on Climate Change
University Corporation for Atmospheric Research
Woods Hole Oceanographic Institution
Woods Hole Research Center
World Association of Zoos and Aquariums
World Federation of Public Health Associations
World Forestry Congress
World Health Organization
World Meteorological Organization
Zambia Academy of Sciences
Zimbabwe Academy of Sciences
Last edited by EdwardHeisler (2017-10-15 14:25:05)
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GLOBAL CLIMATE CHANGE
VITAL SIGNS OF THE PLANET
Read the NASA reports at:
Last edited by EdwardHeisler (2017-10-15 16:25:15)
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If those sea level records are correct then we should by now have seen some stable islands (in areas where the land is not sinking) actually being inundated. I've seen no evidence that's happened.
As for global temperature, I know that central London is often 3 or 4 degrees hotter than the surrounding countryside. With growing population and growing urbanisation there must be an increase in temperatures recorded simply because urban and suburban areas are warmer. How is that accounted for? Statistically? If so, then you are straight into the statistical hall of mirrors where people's beliefs play a large part in the outcome.
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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The Reality of Climate Change: 10 Myths Busted
By Jeanna Bryner, Live Science Managing Editor | April 4, 2012
Dynamic Earth
Earth is a dynamic sphere and, it turns out, so is the planet's climate, otherwise known as the long-term trend of global weather conditions. It's no wonder questions and myths abound about what exactly is going on in the atmosphere, in the oceans and on land. How can we tell our orb is actually warming and whether humans are to blame? Here's a look at what scientists know and don't know about some seemingly murky statements on Earth's climate.
Myth: Even before SUVs and other greenhouse-gas spewing technologies, Earth's climate was changing, so humans can't be responsible for today's global warming.
Science: Climate changes in the past suggest that our climate reacts to energy input and output, such that if the planet accumulates more heat than it gives off global temperatures will rise. It's the driver of this heat imbalance that differs.
Currently, CO2 is imposing an energy imbalance due to the enhanced greenhouse effect. Past climate change actually provides evidence for our climate's sensitivity to CO2.
Myth: The planet can't be warming when my front yard is covered in several feet of snow. … This winter has been one of the chilliest, how is that possible in a warming world?
Science: Local temperatures taken as individual data points have nothing to do with the long-term trend of global warming. These local ups and downs in weather and temperature can hide a slower-moving uptick in long-term climate. To get a real bead on global warming, scientists rely on changes in weather over a long period of time. To find climate trends you need to look at how weather is changing over a longer time span. Looking at high and low temperature data from recent decades shows that new record highs occur nearly twice as often as new record lows.
For instance, a study published in the journal Geophysical Research Letters in 2009, found that daily record high temperatures occurred twice as often as record lows over the prior decade across the continental United States.
Myth: Global warming has stopped and the Earth has begun to cool.
Science: The last decade, 2000-2009, was the hottest on record, according to Skeptical Science. Big blizzards and abnormally chilly weather often raise the question: How can global warming be occurring when it's snowing outside? Global warming is compatible with chilled weather. "For climate change, it is the long-term trends that are important; measured over decades or more, and those long term trends show that the globe is still, unfortunately, warming," according to Skeptical Science.
Myth: Over the past few hundred years, the sun's activity, including the number of sunspots, has increased, causing the world to get warmer.
Science: In the last 35 years of global warming, the sun has shown a slight cooling trend, while the climate has been heating up, scientists say. In the past century, solar activity can explain some of the increase in global temperatures, but a relatively small amount. (Solar activity refers to the activity of the sun's magnetic field and includes magnetic field-powered sunspots and solar flares.)
A study published in the journal Atmospheric Chemistry and Physics in December 2011 revealed that even during a prolonged lull in the sun's activity, Earth still continued to warm. The study researchers found that the Earth absorbed 0.58 watts of excess energy per square meter than escaped back into space during the study period from 2005 to 2010, a time when solar activity was low.
Myth: There's no consensus on whether the planet is actually warming.
Science: About 97 percent of climate scientists agree that human-made global warming is happening. "In the scientific field of climate studies — which is informed by many different disciplines — the consensus is demonstrated by the number of scientists who have stopped arguing about what is causing climate change — and that's nearly all of them," according to Skeptical Science, a website dedicated to explaining the science of global warming.
Myth: Rick Santorum, GOP presidential nominee, summed up this argument in the news when he said: "The dangers of carbon dioxide? Tell that to a plant, how dangerous carbon dioxide is," he told the Associated Press.
Science: While it is true that plants photosynthesize, and therefore take up carbon dioxide as a way of forming energy with the help of the sun and water, this gas is both a direct pollutant (think acidification of oceans) and more importantly is linked to the greenhouse effect. When heat energy gets released from Earth's surface, some of that radiation is trapped by greenhouse gases like CO2; the effect is what makes our planet comfy temperature-wise, but too much and you get global warming.
Myth: Some have pointed to human history as evidence that warm periods are good for people, while the cold, unstable stints have been catastrophic.
Science: Climate scientists say any positives are far outweighed by the negative impacts of global warming on agriculture, human health, the economy and the environment. For instance, according to one 2007 study, a warming planet may mean an increased growing season in Greenland; but it also means water shortages, more frequent and more intense wildfires and expanding deserts.
Myth: Ice covering much of Antarctica is expanding, contrary to the belief that the ice cap is melting due to global warming.
Science: The argument that ice is expanding on Antarctica omit the fact that there's a difference between land ice and sea ice, climate scientists say. "If you are talking about the Antarctic ice sheet, we expect some gain in accumulation in the interior due to warmer, more moisture-laden air, but increased calving/ice loss at the periphery, primarily due to warming southern oceans," climate scientist Michael Mann, of Pennsylvania State University, told LiveScience. The net change in ice mass is the difference between this accumulation and peripheral loss. "Models traditionally have projected that this difference doesn't become negative (i.e. net loss of Antarctic ice sheet mass) for several decades," Mann said, adding that detailed gravimetric measurements, which looks at changes in Earth's gravity over spots to estimate, among other things, ice mass. These measurements, Mann said, suggest the Antarctic ice sheet is already losing mass and contributing to sea level rise.
Myth: Models are full of "fudge factors" or assumptions that make them fit with data collected in today's climate; there's no way to know if those same assumption can be made in a world with increased carbon dioxide.
Science: Models have successfully reproduced global temperatures since 1900, by land, in the air and the oceans. "Models are simply a formalization of our best understanding of the processes that govern the atmosphere, the oceans, the ice sheets, etc.," Mann said. He added that certain processes, such as how clouds will respond to changes in the atmosphere and the warming or cooling effect of clouds, are uncertain and different modeling groups make different assumptions about how to represent these processes.
Even so, Mann said, certain predictions are based on physics and chemistry that are so fundamental, such as the atmospheric greenhouse effect, that the resulting predictions — that surface temperatures should warm, ice should melt and sea level should rise — are robust no matter the assumptions.
Skeptic Arguments and What The Science Says
Here is a summary of global warming and climate change myths, sorted by recent popularity vs what science says.
1 "Climate's changed before" Climate reacts to whatever forces it to change at the time; humans are now the dominant forcing.
2 "It's the sun"
In the last 35 years of global warming, sun and climate have been going in opposite directions
3 "It's not bad" Negative impacts of global warming on agriculture, health & environment far outweigh any positives.
4 "There is no consensus"
97% of climate experts agree humans are causing global warming.
5 "It's cooling" The last decade 2000-2009 was the hottest on record.
6 "Models are unreliable" Models successfully reproduce temperatures since 1900 globally, by land, in the air and the ocean.
7 "Temp record is unreliable" The warming trend is the same in rural and urban areas, measured by thermometers and satellites.
8 "Animals and plants can adapt" Global warming will cause mass extinctions of species that cannot adapt on short time scales.
9 "It hasn't warmed since 1998"
Every part of the Earth's climate system has continued warming since 1998, with 2015 shattering temperature records.
10 "Antarctica is gaining ice" Satellites measure Antarctica losing land ice at an accelerating rate.
11 "Ice age predicted in the 70s" The vast majority of climate papers in the 1970s predicted warming.
12 "CO2 lags temperature" CO2 didn't initiate warming from past ice ages but it did amplify the warming.
13 "Climate sensitivity is low" Net positive feedback is confirmed by many different lines of evidence.
14 "We're heading into an ice age" Worry about global warming impacts in the next 100 years, not an ice age in over 10,000 years.
15 "Ocean acidification isn't serious" Ocean acidification threatens entire marine food chains.
16 "Hockey stick is broken" Recent studies agree that recent global temperatures are unprecedented in the last 1000 years.
17 "Climategate CRU emails suggest conspiracy" A number of investigations have cleared scientists of any wrongdoing in the media-hyped email incident.
18 "Hurricanes aren't linked to global warming" There is increasing evidence that hurricanes are getting stronger due to global warming.
19 "Al Gore got it wrong"
Al Gore's book is quite accurate, and far more accurate than contrarian books.
20 "Glaciers are growing" Most glaciers are retreating, posing a serious problem for millions who rely on glaciers for water.
21 "It's cosmic rays" Cosmic rays show no trend over the last 30 years & have had little impact on recent global warming.
22 "1934 - hottest year on record" 1934 was one of the hottest years in the US, not globally.
23 "It's freaking cold!" A local cold day has nothing to do with the long-term trend of increasing global temperatures.
24 "Extreme weather isn't caused by global warming" Extreme weather events are being made more frequent and worse by global warming.
25 "Sea level rise is exaggerated" A variety of different measurements find steadily rising sea levels over the past century.
26 "It's Urban Heat Island effect" Urban and rural regions show the same warming trend.
27 "Medieval Warm Period was warmer" Globally averaged temperature now is higher than global temperature in medieval times.
28 "Mars is warming"
Mars is not warming globally.
29 "Arctic icemelt is a natural cycle"
Thick Arctic sea ice is undergoing a rapid retreat.
30 "Increasing CO2 has little to no effect" The strong CO2 effect has been observed by many different measurements.
31 "Oceans are cooling" The most recent ocean measurements show consistent warming.
32 "It's a 1500 year cycle"
Ancient natural cycles are irrelevant for attributing recent global warming to humans.
33 "Human CO2 is a tiny % of CO2 emissions" The natural cycle adds and removes CO2 to keep a balance; humans add extra CO2 without removing any.
34 "IPCC is alarmist"
Numerous papers have documented how IPCC predictions are more likely to underestimate the climate response.
35 "Water vapor is the most powerful greenhouse gas"
Rising CO2 increases atmospheric water vapor, which makes global warming much worse.
36 "Polar bear numbers are increasing" Polar bears are in danger of extinction as well as many other species.
37 "CO2 limits will harm the economy"
The benefits of a price on carbon outweigh the costs several times over.
38 "It's not happening"
There are many lines of evidence indicating global warming is unequivocal.
39 "Greenland was green" Other parts of the earth got colder when Greenland got warmer.
40 "Greenland is gaining ice" Greenland on the whole is losing ice, as confirmed by satellite measurement.
41 "CO2 is not a pollutant"
Through its impacts on the climate, CO2 presents a danger to public health and welfare, and thus qualifies as an air pollutant
42 "There's no empirical evidence" There are multiple lines of direct observations that humans are causing global warming.
43 "CO2 is plant food"
The effects of enhanced CO2 on terrestrial plants are variable and complex and dependent on numerous factors
44 "Other planets are warming" Mars and Jupiter are not warming, and anyway the sun has recently been cooling slightly.
45 "It's clouds"
46 "Arctic sea ice has recovered" Thick arctic sea ice is in rapid retreat.
47 "There's no correlation between CO2 and temperature" There is long-term correlation between CO2 and global temperature; other effects are short-term.
48 "We're coming out of the Little Ice Age"
Scientists have determined that the factors which caused the Little Ice Age cooling are not currently causing global warming
49 "It cooled mid-century" Mid-century cooling involved aerosols and is irrelevant for recent global warming.
50 "Global warming stopped in 1998, 1995, 2002, 2007, 2010, ????"
Global temperature is still rising and 2010 was the hottest recorded.
51 "CO2 was higher in the past"
When CO2 was higher in the past, the sun was cooler.
52 "It warmed before 1940 when CO2 was low" Early 20th century warming is due to several causes, including rising CO2.
53 "Satellites show no warming in the troposphere" The most recent satellite data show that the earth as a whole is warming.
54 "It's aerosols"
Aerosols have been masking global warming, which would be worse otherwise.
55 "2009-2010 winter saw record cold spells"
A cold day in Chicago in winter has nothing to do with the trend of global warming.
56 "It's El Niño" El Nino has no trend and so is not responsible for the trend of global warming.
57 "Mt. Kilimanjaro's ice loss is due to land use"
Most glaciers are in rapid retreat worldwide, notwithstanding a few complicated cases.
58 "It's not us" Multiple sets of independent observations find a human fingerprint on climate change.
59 "It's a natural cycle"
No known natural forcing fits the fingerprints of observed warming except anthropogenic greenhouse gases.
60 "There's no tropospheric hot spot"
We see a clear "short-term hot spot" - there's various evidence for a "long-term hot spot".
61 "It's Pacific Decadal Oscillation"
The PDO shows no trend, and therefore the PDO is not responsible for the trend of global warming.
62 "Scientists can't even predict weather" Weather and climate are different; climate predictions do not need weather detail.
63 "IPCC were wrong about Himalayan glaciers"
Glaciers are in rapid retreat worldwide, despite 1 error in 1 paragraph in a 1000 page IPCC report.
64 "2nd law of thermodynamics contradicts greenhouse theory" The 2nd law of thermodynamics is consistent with the greenhouse effect which is directly observed.
65 "Greenhouse effect has been falsified" The greenhouse effect is standard physics and confirmed by observations.
66 "CO2 limits will hurt the poor"
Those who contribute the least greenhouse gases will be most impacted by climate change.
67 "Clouds provide negative feedback" Evidence is building that net cloud feedback is likely positive and unlikely to be strongly negative.
68 "The science isn't settled" That human CO2 is causing global warming is known with high certainty & confirmed by observations.
69 "Sea level rise predictions are exaggerated" Sea level rise is now increasing faster than predicted due to unexpectedly rapid ice melting.
70 "It's the ocean" The oceans are warming and moreover are becoming more acidic, threatening the food chain.
71 "IPCC were wrong about Amazon rainforests"
The IPCC statement on Amazon rainforests was correct, and was incorrectly reported in some media.
72 "Corals are resilient to bleaching" Globally about 1% of coral is dying out each year.
73 "CO2 effect is saturated" Direct measurements find that rising CO2 is trapping more heat.
74 "Volcanoes emit more CO2 than humans"
Humans emit 100 times more CO2 than volcanoes.
75 "Greenland ice sheet won't collapse"
When Greenland was 3 to 5 degrees C warmer than today, a large portion of the Ice Sheet melted.
76 "500 scientists refute the consensus" Around 97% of climate experts agree that humans are causing global warming.
77 "CO2 is just a trace gas"
Many substances are dangerous even in trace amounts; what really matters is the total amount of CO2 in the atmosphere.
78 "It's methane" Methane plays a minor role in global warming but could get much worse if permafrost starts to melt.
79 "CO2 has a short residence time"
Excess CO2 from human emissions has a long residence time of over 100 years
80 "CO2 measurements are suspect" CO2 levels are measured by hundreds of stations across the globe, all reporting the same trend.
81 "Humidity is falling" Multiple lines of independent evidence indicate humidity is rising and provides positive feedback.
82 "Neptune is warming" And the sun is cooling.
83 "Springs aren't advancing" Hundreds of flowers across the UK are flowering earlier now than any time in 250 years.
84 "Jupiter is warming" Jupiter is not warming, and anyway the sun is cooling.
85 "It's land use"
Land use plays a minor role in climate change, although carbon sequestration may help to mitigate.
86 "CO2 is not increasing" CO2 is increasing rapidly, and is reaching levels not seen on the earth for millions of years.
87 "Scientists tried to 'hide the decline' in global temperature" The 'decline' refers to a decline in northern tree-rings, not global temperature, and is openly discussed in papers and the IPCC reports.
88 "Record snowfall disproves global warming" Warming leads to increased evaporation and precipitation, which falls as increased snow in winter.
89 "They changed the name from 'global warming' to 'climate change'"
'Global warming' and 'climate change' mean different things and have both been used for decades.
90 "Solar Cycle Length proves its the sun" The sun has not warmed since 1970 and so cannot be driving global warming.
91 "CO2 is coming from the ocean"
The ocean is absorbing massive amounts of CO2, and is becoming more acidic as a result.
92 "IPCC overestimate temperature rise"
Monckton used the IPCC equation in an inappropriate manner.
93 "Pluto is warming"
And the sun has been recently cooling.
94 "CO2 is not the only driver of climate"
Theory, models and direct measurement confirm CO2 is currently the main driver of climate change.
95 "Peer review process was corrupted" An Independent Review concluded that CRU's actions were normal and didn't threaten the integrity of peer review.
96 "Arctic was warmer in 1940"
The actual data show high northern latitudes are warmer today than in 1940.
97 "Renewable energy is too expensive"
When you account for all of the costs associated with burning coal and other fossil fuels, like air pollution and health effects, in reality they are significantly more expensive than most renewable energy sources.
98 "Southern sea ice is increasing" Antarctic sea ice has grown in recent decades despite the Southern Ocean warming at the same time.
99 "Sea level rise is decelerating"
Global sea level data shows that sea level rise has been increasing since 1880 while future sea level rise predictions are based on physics, not statistics.
100 "CO2 limits will make little difference"
If every nation agrees to limit CO2 emissions, we can achieve significant cuts on a global scale.
101 "It's microsite influences"
Microsite influences on temperature changes are minimal; good and bad sites show the same trend.
102 "Lindzen and Choi find low climate sensitivity" Lindzen and Choi’s paper is viewed as unacceptably flawed by other climate scientists.
103 "Phil Jones says no global warming since 1995" Phil Jones was misquoted.
104 "Humans are too insignificant to affect global climate" Humans are small but powerful, and human CO2 emissions are causing global warming.
105 "Infrared Iris will reduce global warming"
The iris hypothesis has not withstood the test of time - subsequent research has found that if it exists, the effect is much smaller than originally hypothesized, and may even slightly amplify rather than reducing global warming.
106 "Dropped stations introduce warming bias" If the dropped stations had been kept, the temperature would actually be slightly higher.
107 "It's too hard" Scientific studies have determined that current technology is sufficient to reduce greenhouse gas emissions enough to avoid dangerous climate change.
108 "It's not urgent"
A large amount of warming is delayed, and if we don’t act now we could pass tipping points.
109 "It's albedo" Albedo change in the Arctic, due to receding ice, is increasing global warming.
110 "Tree-rings diverge from temperature after 1960" This is a detail that is complex, local, and irrelevant to the observed global warming trend.
111 "It's soot"
Soot stays in the atmosphere for days to weeks; carbon dioxide causes warming for centuries.
112 "Roy Spencer finds negative feedback" Spencer's model is too simple, excluding important factors like ocean dynamics and treats cloud feedbacks as forcings.
113 "Hansen's 1988 prediction was wrong"
Jim Hansen had several possible scenarios; his mid-level scenario B was right.
114 "It's global brightening" This is a complex aerosol effect with unclear temperature significance.
115 "Earth hasn't warmed as much as expected" This argument ignores the cooling effect of aerosols and the planet's thermal inertia.
116 "Arctic sea ice loss is matched by Antarctic sea ice gain" Arctic sea ice loss is three times greater than Antarctic sea ice gain.
117 "It's a climate regime shift"
There is no evidence that climate has chaotic “regimes” on a long-term basis.
118 "Solar cycles cause global warming" Over recent decades, the sun has been slightly cooling & is irrelevant to recent global warming.
119 "Less than half of published scientists endorse global warming"
Around 97% of climate experts agree that humans are causing global warming.
120 "A drop in volcanic activity caused warming" Volcanoes have had no warming effect in recent global warming - if anything, a cooling effect.
121 "Plant stomata show higher and more variable CO2 levels"
Stomatal data is not as direct as ice core measurements and hence not as precise.
122 "Over 31,000 scientists signed the OISM Petition Project"
The 'OISM petition' was signed by only a few climatologists.
123 "Ice isn't melting"
Arctic sea ice has shrunk by an area equal to Western Australia, and summer or multi-year sea ice might be all gone within a decade.
124 "IPCC ‘disappeared’ the Medieval Warm Period"
The IPCC simply updated their temperature history graphs to show the best data available at the time.
125 "Sea level is not rising"
The claim sea level isn’t rising is based on blatantly doctored graphs contradicted by observations.
126 "It's ozone"
Ozone has only a small effect.
127 "Climate is chaotic and cannot be predicted" Weather is chaotic but climate is driven by Earth's energy imbalance, which is more predictable.
128 "Freedom of Information (FOI) requests were ignored" An independent inquiry found CRU is a small research unit with limited resources and their rigour and honesty are not in doubt.
129 "Climate 'Skeptics' are like Galileo"
Modern scientists, not anti-science skeptics, follow in Galileo’s footsteps.
130 "The IPCC consensus is phoney"
113 nations signed onto the 2007 IPCC report, which is simply a summary of the current body of climate science evidence
131 "Tuvalu sea level isn't rising" Tuvalu sea level is rising 3 times larger than the global average.
132 "Naomi Oreskes' study on consensus was flawed" Benny Peiser, the Oreskes critic, retracted his criticism.
133 "Renewables can't provide baseload power"
A number of renewable sources already do provide baseload power, and we don't need renewables to provide a large percentage of baseload power immediately.
134 "Trenberth can't account for the lack of warming"
Trenberth is talking about the details of energy flow, not whether global warming is happening.
135 "Ice Sheet losses are overestimated" A number of independent measurements find extensive ice loss from Antarctica and Greenland.
136 "CRU tampered with temperature data" An independent inquiry went back to primary data sources and were able to replicate CRU's results.
137 "Melting ice isn't warming the Arctic" Melting ice leads to more sunlight being absorbed by water, thus heating the Arctic.
138 "Breathing contributes to CO2 buildup" By breathing out, we are simply returning to the air the same CO2 that was there to begin with.
139 "Satellite error inflated Great Lakes temperatures" Temperature errors in the Great Lakes region are not used in any global temperature records.
140 "Soares finds lack of correlation between CO2 and temperature"
Soares looks at short-term trends which are swamped by natural variations while ignoring the long-term correlation.
141 "We're heading into cooling" There is no scientific basis for claims that the planet will begin to cool in the near future.
142 "Murry Salby finds CO2 rise is natural"
Multiple lines of evidence make it very clear that the rise in atmospheric CO2 is due to human emissions.
143 "The sun is getting hotter" The sun has just had the deepest solar minimum in 100 years.
144 "Most of the last 10,000 years were warmer"
This argument uses regional temperature data that ends in 1855, long before modern global warming began.
145 "CO2 emissions do not correlate with CO2 concentration" That humans are causing the rise in atmospheric CO2 is confirmed by multiple isotopic analyses.
146 "It's waste heat"
Greenhouse warming is adding 100 times more heat to the climate than waste heat.
147 "Water vapor in the stratosphere stopped global warming" This possibility just means that future global warming could be even worse.
148 "It warmed just as fast in 1860-1880 and 1910-1940" The warming trend over 1970 to 2001 is greater than warming from both 1860 to 1880 and 1910 to 1940.
149 "An exponential increase in CO2 will result in a linear increase in temperature"
CO2 levels are rising so fast that unless we decrease emissions, global warming will accelerate this century.
150 "Record high snow cover was set in winter 2008/2009"
Winter snow cover in 2008/2009 was average while the long-term trend in spring, summer, and annual snow cover is rapid decline.
151 "Mauna Loa is a volcano"
The global trend is calculated from hundreds of CO2 measuring stations and confirmed by satellites.
152 "CERN CLOUD experiment proved cosmic rays are causing global warming"
The CERN CLOUD experiment only tested one-third of one out of four requirements necessary to blame global warming on cosmic rays, and two of the other requirements have already failed.
153 "97% consensus on human-caused global warming has been disproven"
The 97% consensus has been independently confirmed by a number of different approaches and lines of evidence.
154 "Venus doesn't have a runaway greenhouse effect"
Venus very likely underwent a runaway or ‘moist’ greenhouse phase earlier in its history, and today is kept hot by a dense CO2 atmosphere.
155 "Deniers are part of the 97%"
If anyone claims to be part of the 97 percent, it means they disagree with the contrarian argument that humans are having a minimal impact on global warming.
156 "Water levels correlate with sunspots"
This detail is irrelevant to the observation of global warming caused by humans.
157 "It's planetary movements"
Blaming global warming on the movements of other planets is little more than 'climastrology' and curve fitting without a physical basis.
158 "Antarctica is too cold to lose ice" Glaciers are sliding faster into the ocean because ice shelves are thinning due to warming oceans.
159 "Positive feedback means runaway warming" Positive feedback won't lead to runaway warming; diminishing returns on feedback cycles limit the amplification.
160 "Skeptics were kept out of the IPCC?"
Official records, Editors and emails suggest CRU scientists acted in the spirit if not the letter of IPCC rules.
161 "CO2 was higher in the late Ordovician"
The sun was much cooler during the Ordovician.
162 "Coral atolls grow as sea levels rise"
Thousands of coral atolls have "drowned" when unable to grow fast enough to survive at sea level.
163 "It's internal variability"
Internal variability can only account for small amounts of warming and cooling over periods of decades, and scientific studies have consistently shown that it cannot account for the global warming over the past century.
164 "CO2 increase is natural, not human-caused" Many lines of evidence, including simple accounting, demonstrate beyond a shadow of a doubt that the increase in atmospheric CO2 is due to human fossil fuel burning.
165 "No warming in 16 years"
Global surface temperatures have continued to rise steadily beneath short-term natural cooling effects, and the rise in global heat content has not slowed at all.
166 "A grand solar minimum could trigger another ice age"
Peer-reviewed research, physics, and math all tell us that a grand solar minimum would have no more than a 0.3°C cooling effect, barely enough to put a dent in human-caused global warming.
167 "Adapting to global warming is cheaper than preventing it"
Preventing global warming is relatively cheap; business-as-usual will cause accelerating climate damage costs that economists struggle to even estimate.
168 "It's CFCs"
CFCs contribute at a small level.
169 "Scientists retracted claim that sea levels are rising"
The Siddall 2009 paper was retracted because its predicted sea level rise was too low.
170 "Warming causes CO2 rise" Recent warming is due to rising CO2.
171 "Renewable energy investment kills jobs"
Investment in renewable energy creates more jobs than investment in fossil fuel energy.
172 "Schmittner finds low climate sensitivity"
The Schmittner et al. study finds low probability of both very low and very high climate sensitivities, and its lower estimate (as compared to the IPCC) is based on a new temperature reconstruction of the Last Glacial Maximum that may or may not withstand the test of time.
173 ""
The 97% consensus on human-caused global warming is a robust result using two independent methods (volunteer abstract ratings and scientist self-ratings) and consistent with similar previous surveys.
174 "Greenland has only lost a tiny fraction of its ice mass" Greenland's ice loss is accelerating & will add metres of sea level rise in upcoming centuries.
175 "DMI show cooling Arctic" While summer maximums have showed little trend, the annual average Arctic temperature has risen sharply in recent decades.
176 "Ben Santer and the 1995 IPCC report"
The IPCC operates by consensus. Ben Santer could not have and did not single-handedly alter the 1995 IPCC report. Accusations to the contrary are simply an attempt to re-write history.
177 "CO2 limits won't cool the planet"
CO2 limits won't cool the planet, but they can make the difference between continued accelerating global warming to catastrophic levels vs. slowing and eventually stopping the warming at hopefully safe levels
178 "It's a climate shift step function caused by natural cycles"
Natural cycles superimposed on a linear warming trend can be mistaken for step changes, but the underlying warming is caused by the external radiative forcing.
179 "Royal Society embraces skepticism" The Royal Society still strongly state that human activity is the dominant cause of global warming.
180 "It's only a few degrees" A few degrees of global warming has a huge impact on ice sheets, sea levels and other aspects of climate.
181 "It's satellite microwave transmissions"
Satellite transmissions are extremely small and irrelevant.
182 "CO2 only causes 35% of global warming"
CO2 and corresponding water vapor feedback are the biggest cause of global warming.
183 "IPCC graph showing accelerating trends is misleading"
All of the statements made in the IPCC report regarding the figure in question are correct and supported.
184 "Sea level fell in 2010" The temporary drop in sea level in 2010 was due to intense land flooding caused by a strong La Nina.
185 "Arctic sea ice extent was lower in the past"
Current Arctic sea ice extent is the lowest in the past several thousand years.
186 "UAH atmospheric temperatures prove climate models and/or surface temperature data sets are wrong"
The most likely explanation for UAH data warming less than expected is that the UAH data set is biased low.
187 "We didn't have global warming during the Industrial Revolution" CO2 emissions were much smaller 100 years ago.
188 "Ljungqvist broke the hockey stick"
Ljungqvist's temperature reconstruction is very similar to other reconstructions by Moberg and Mann.
189 "Hansen predicted the West Side Highway would be underwater"
Hansen was speculating on changes that might happen if CO2 doubled.
190 "Removing all CO2 would make little difference"
Removing CO2 would cause most water in the air to rain out and cancel most of the greenhouse effect.
191 "Great Barrier Reef is in good shape" Evidence clearly shows that both ocean warming and acidification due to human CO2 emissions are damaging the Great Barrier Reef
192 "Loehle and Scafetta find a 60 year cycle causing global warming"
Loehle and Scafetta's paper is nothing more than a curve fitting exercise with no physical basis using an overly simplistic model.
193 "Postma disproved the greenhouse effect" Postma's model contains many simple errors; in no way does Postma undermine the existence or necessity of the greenhouse effect.
194 "Underground temperatures control climate"
The amount of heat energy coming out of the Earth is too small to even be worth considering.
195 "Humans survived past climate changes"
Humans have been through climate changes before- but mostly cold ones and mostly in our far distant past.
196 "Heatwaves have happened before"
Global warming is increasing the frequency, duration and intensity of heatwaves.
197 "Climate change isn't increasing extreme weather damage costs"
The data and research are unclear whether climate change is increasing extreme weather damage costs, but many types of extreme weather are becoming more intense and/or frequent, and disaster costs from extreme weather events are rising.
Click on the following link and the response for a more detailed response.
https://skepticalscience.com/argument.php
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If you don't want to discuss the evidence, fair enough...you're simply arguing from authority which isn't an argument or listing assertions.
If rural areas show the "same" warming trend (to quote your claim) as areas that have been urbanised or suburbanised, that makes no sense at all. If AGW is true, there should still be a marked difference in the warming trend between rural and recently urbanised areas. Then what counts as "rural" - an isolated airport? Well most airports have grown dramatically in the last few decades and have been warming themselves as they grow. Who defines rural, surburban or urban?
Temperatures have to go up or down on average. The chances of them staying exactly the same are virtually zero. I don't think anyone is arguing that there has been an average temperature rise. How much it is in reality remains to be seen and the idea in any case that global warming is "bad" for the planet as a whole is extremely doubtful.
Finally, it's clear that fossil fuel energy is going to be beaten on unsubsidised price by solar plus storage within the next 20-30 years just about everywhere on the planet. It's not as though we are going to carry on pumping out CO2.
Last edited by louis (2017-10-15 15:48:02)
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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Closed minds do not accept evidence or argument.
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Just want to let you know that we do have a topic on this subject that you can also read through....
When Science becomes perverted by Politics.
There are many factors that cause the warming tripping point to go up as well that we know that we can slide it the other way as well.
Just as monitoring Co2 in the atmospher and water are not the only factors to any global warming.....
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I am always amazed at how people completely ignore irrigation. The amount of irrigation going on now is many, many times more than 50 years ago and that means much more water is being pumped into the atmosphere (as vapour) rather than into the oceans (as water). No one really knows whether water vapour is a positive or a negative for global warming (since clouds also reflect) but assuming it is a positive, then I am amazed no one really looks into this, while all research is focussed on CO2.
Just want to let you know that we do have a topic on this subject that you can also read through....
When Science becomes perverted by Politics.
There are many factors that cause the warming tripping point to go up as well that we know that we can slide it the other way as well.
Just as monitoring Co2 in the atmospher and water are not the only factors to any global warming.....
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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So why would we need to irrigate needs to be answered....as heat will cause the soil to dry right, so where is the heat coming from.....
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I am always amazed at how people completely ignore irrigation. The amount of irrigation going on now is many, many times more than 50 years ago and that means much more water is being pumped into the atmosphere (as vapour) rather than into the oceans (as water). No one really knows whether water vapour is a positive or a negative for global warming (since clouds also reflect) but assuming it is a positive, then I am amazed no one really looks into this, while all research is focussed on CO2.
From what I learned in my atmosphere class, although water vapor contributes more to the greenhouse effect than CO2, it's not as problematic since it precipitates out of the atmosphere as rain. That being said, I could very well see how irrigation and thus increased H2O in the atmosphere might contribute to increased warming.
The Earth is the cradle of the mind, but one cannot live in a cradle forever. -Paraphrased from Tsiolkovsky
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How climate change is "turning up the dial" on California wildfires
Experts say fires like those burning up California wine country will be more frequent, more intense and last longer as global temperatures rise. While no single fire can be said to have been caused by climate change, variations in temperature and precipitation are already affecting the complex dynamics that determine how wildfires develop and spread.
"With a warming climate, dry weather and reducing moisture, these kinds of catastrophes have happened and will continue to happen and we have to be ready to mitigate, and it's going to cost a lot of money," Brown said.
Scientists and fire experts back up that claim. They point to an alarming increase in the severity and frequency of wildfires in the West over the past several years, warning that the problem is only going to get worse.
Somewhat counterintuitively, more rain and snow in the winter lays the groundwork for more destructive wildfires. More precipitation in the winter means more vegetation can grow in the spring. Over the summer months, that vegetation dries out and becomes the fuel that feeds wildfires when ignited.
Higher temperatures in the summer months mean the trees, brush and grass are significantly drier once fire season rolls around. High-speed Diablo winds from the interior of the continent and increased evaporation due to higher temperatures contribute to drying out the plant life. Higher temperatures also mean fire season lasts longer.
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Water vapour doesn't immediately precipitate as rain or snow...conditions have to be right and so until it does the clouds are acting as a heat trap, of that there is no doubt (I can definitely vouch for that living in the UK where clouds = warmer and clear sky = colder). The only question is how far the reflective quality of clouds matches the heat trap effect in terms of overall insolation. There can be no doubt that huge irrigation schemes = more clouds.
louis wrote:I am always amazed at how people completely ignore irrigation. The amount of irrigation going on now is many, many times more than 50 years ago and that means much more water is being pumped into the atmosphere (as vapour) rather than into the oceans (as water). No one really knows whether water vapour is a positive or a negative for global warming (since clouds also reflect) but assuming it is a positive, then I am amazed no one really looks into this, while all research is focussed on CO2.
From what I learned in my atmosphere class, although water vapor contributes more to the greenhouse effect than CO2, it's not as problematic since it precipitates out of the atmosphere as rain. That being said, I could very well see how irrigation and thus increased H2O in the atmosphere might contribute to increased warming.
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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Ireland and Britain Brace for Unusual European Hurricane
The New York Times
By SUSANNE FOWLER
LONDON — Rain is no stranger to Ireland, but hurricanes?
Hurricane Ophelia, the 10th hurricane of the Atlantic season, was spinning toward Ireland on Sunday, bringing with it the potential for structural damage, significant coastal flooding and dangerously high seas.
In London, the Met Office, Britain’s meteorological service, said that Ophelia had been the most-eastern Category 3 Atlantic hurricane on record.
The last time weather watchers recorded 10 consecutive Atlantic hurricanes was in 1893.
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GLOBAL WARMING? HUMBUG!
LOL
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It's not a hurricane. The fact that the NYT are pretending it's still a hurricane that's hitting Ireland is indicative of how people propagandise on behalf of AGW. We had a really bad storm in 1987 in the UK - known as the Great Storm. Since then, nothing as destructive. What does that prove? Nothing either way. You can always find a weather record. Truth is until this year, we've had a v. quiet period for hurricanes.
https://www.ncdc.noaa.gov/sotc/tropical-cyclones/201613
The tropical storm figures in the Atlantic basin look like they have dropped significantly since 2006, compared with the previous period. No doubt you'll find some way to show that is indicative of global warming.
You can always find a "record" for something if you really want to.
Ireland and Britain Brace for Unusual European Hurricane
The New York Times
By SUSANNE FOWLERLONDON — Rain is no stranger to Ireland, but hurricanes?
Hurricane Ophelia, the 10th hurricane of the Atlantic season, was spinning toward Ireland on Sunday, bringing with it the potential for structural damage, significant coastal flooding and dangerously high seas.In London, the Met Office, Britain’s meteorological service, said that Ophelia had been the most-eastern Category 3 Atlantic hurricane on record.
The last time weather watchers recorded 10 consecutive Atlantic hurricanes was in 1893.
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GLOBAL WARMING? HUMBUG!
LOL
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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Very long post. And I've had this argument so many times that I'm tired of it. Let me start by saying I used to believe in environmental stuff, but then "climate warriors" started claiming all fossil fuels must stay in the ground, they want to shut down all coal mines, all oil wells, all tar sands, even all natural gas. They want to shut down all oil pipelines. Cold turkey on all fossil fuels. That's just not possible!
The main problem is most people who believe anything on this issue fall into one of two camps: climate change deniers who try to claim climate change isn't happening, or climate warriors who claim the sky is falling. Of course the truth is somewhere in the middle.
Science documents global cooling from the beginning of the industrial revolution of 1855 until 1970. There was global warming during World War 1 and World War 2, but even between the wars there was global cooling. In the 1960s and 1970s, scientists were extremely worried about global cooling. They thought an interglacial period lasts 10,000 years, and it's been 11,000 years since the end of the last ice age, so we're over due for the next one. Some scientists seriously suggested dropping big thermonuclear bombs on the polls to halt global cooling. Luckily other scientists pointed out how much radioactive fallout that would cause, so no one did it. Then in 1979 one scientist published a paper about global warming. The entire science community at the time responded with "Are you nuts?!? Get with the program!!! We just spent two decades on the problem of global cooling!" But science is not a democracy, it doesn't matter how many agree with you, the only thing that matters is the data. He had data to back up is claims. They checked his data, doubled checked, triple checked, and checked again. It clearly showed global warming since 1970. Remember this was 1979, so global warming only existed for 9 years at that time. Data still showed global cooling form 1855 until 1970. Scientists were still skeptical, worried he "cherry picked" data that agrees with what he wanted to say, so checked outer sources. When that still agreed, they took new measurements. It all confirmed global warming.
But just as the entire establishment was skeptical about change then, an even broader establishment doesn't want to hear anything now.
Since year 2000, global warming has dramatically slowed. In fact it is a little faster than the pace of nature, but not much. From year 2000 until late 2014, the pace of global warming was so close to the pace of nature that you could say "good enough". In fact several scientists have published papers saying exactly that. But many scientists get funding to work on global warming, they don't want to jeopardize that funding.
Details: industry in 1855 burned coal to fire steam engines. Diesel-electric locomotives were developed from the early 1890s to late 19-teens, went into production in 1920. Some railroad companies replaced steam locomotives with diesel-electric throughout the 1920s, however here in Canada the CN railroad still used steam in the 1960s. A coal-burning steam power plant was built in downtown Winnipeg after a major storm brought down a power line from hydroelectric dams in northern Manitoba. That prevented blackouts, and hot water from condensed steam was piped to office buildings downtown. The last buildings stopped using it in the 1980s. Some cities started enacted pollution control in the 1880s, but the US federal government didn't start until 1928. At that time it was just "monitoring" in eastern cities. Throughout the 1950s pollution controls became more strict, and more so through the 1960s. In 1970 Congress re-wrote the "Clean Air Act". Notice global climate changed reversed from cooling to warming in 1970. Not a coincidence.
Smoke and soot from coal burning are "aerosols" that block sunlight. A dark cloud can block sunlight; ever feel a warm summer day, then a dark cloud passes overhead and you can feel a wave of cool pass over you as the shadow of that cloud? Coal smoke can do that. When industry began in 1855, smoke stacks just drew smoke out of the building, spewing soot over the immediate neighbourhood. People complained, so factories had to do something. They built taller smoke stacks, which spewed soot farther down-wind. People in that neighbourhood complained. So factory owners hired engineers who designed a tall smoke stack with a round cross-section instead of square, which would create an up-draft to draw smoke and soot into the clouds. They realized the soot would eventually fall when those clouds rained, but hoped it would be an uninhabited forest, and most importantly wherever it fell couldn't be trace back to them. However, it turned out these smoke stacks created such a good up-draft that it drew smoke and soot into the lower stratosphere. We live in the troposphere, the lower atmosphere close to the ground. Commercial jet airliners fly in the lower stratosphere, but in the 1800s there were no aircraft. The troposphere and stratosphere do not mix well, once something gets into the stratosphere, it's very difficult to get it out. It took decades to recover from 115 years of man-made global cooling.
As of year 1994, the temperature of the planet equalled what it was before the industrial revolution of 1855. Yes, that means all the global warming from 1970 to 1994 undid the man-made global cooling. But that doesn't take into account natural global warming. We're in an interglacial period, still warming out of the last ice age. Science has been able to reconstruct temperatures from 1550 to 1855; that's 305 years before the industrial revolution. There was very slow and steady natural global warming. If you assume the planet would have continued at that pace, then in year 2000 the temperature of the planet is what it would have been if humans hadn't messed with it. Notice what I just said. All the global warming that nature would have done from 1855 to year 2000, that's 145 years, was condensed to just 6 years, from 1994 to year 2000. That makes it look bad. But still, it doesn't change the fact that as of year 2000, the temperature was what it would have been if humans hadn't messed with it.
In year 2000, the rate of global warming dramatically slowed. Again, that's not coincidence. There's a deep ocean cycle that takes 1,000 years to completely one cycle. That will push the climate back to nature's schedule. So when we removed pollution, that contributed to restore the natural climate. From year 2000 until late 2014, the rate of global warming was almost the pace of nature. Again, I'm assuming the rate of global warming from 1550 to 1855 is the pace of nature. The rate from year 2000 to late 2014 was a little faster than nature, but good enough.
Soot in the lower stratosphere did a couple things. It dimmed sunlight causing global cooling, but also prevented radiant heat from escaping into space. That caused days to warm slowly, and nights to cool slowly. That changed weather to be mild, calm, predictable. Remember scientists tried to predict weather from the Renaissance, starting 1300. They weren't able to. That wasn't because they were stupid, scientists back then were just as smart as scientists today. Weather was far more extreme, chaotic, unpredictable. In the 20th century weather changed, became far more mild, consistent, predictable. Only then could science develop methods to predict weather. Now we have satellites and supercomputers to model the atmosphere of the entire planet, so the ability to deal with weather that is once again chaotic and extreme. But realize this extreme weather is not just due to global warming, it's also due to our blanket of soot in the stratosphere. Radiant heat at night can escape into space. I don't know about you, but I don't want the pollution back. But if we don't restore the blanket of soot in the atmosphere, we will continue to have extreme weather. This is our planet's natural weather.
According to NOAA, the number of tropical storms in the Atlantic has not increased. The proportion that intensify to become hurricanes has. Hurricanes are a giant convection current, carrying heat from the surface of the ocean to the top of the troposphere. Scientists have measured the temperature of the lower stratosphere since 1990. It has been dropping steadily. It spiked up when volcanoes erupted: Mount Pinatubo and that Icelandic volcano who's name I cannot pronounce. My ex is of Icelandic descent, so I have a bit of a mental block there. In both cases the temperature of the lower stratosphere increased, then plummeted. Not just to what was or what it would have been, it dropped significantly lower. Then stabilized, continued to cool at the same pace as before the eruption. Volcanic ash had caused warmed the stratosphere, then flushed out soot. This is mother nature cleaning up our mess. As of year 2010, the temperature of the lower stratosphere has completely stabilized, it isn't dropping any more. Air quality measurements state the only soot that remains in the lower stratosphere since 2010 is from jet aircraft exhaust. This confirms that global climate change is driven by removing pollution, not carbon emissions. But realize the consequence. The top of a hurricane is the top of the troposphere, where it touches the lower stratosphere. During hurricane season in the Caribbean and Gulf of Mexico, the lower stratosphere is -60°C. Hurricanes are convection currents, driven by temperature difference. Surface water has increased in temperature, while the lower stratosphere has dramatically cooled. That increased the temperature difference at both ends. That has increase the number and intensity of hurricanes. But again, this is our planet's natural weather. How many hurricanes existed in the first half of the 1800s? Were weather records even kept then?
I did say the temperature in year 2000 is what it would have been, and the pace of warming from then until late 2014 was so close to nature that it's good enough. Unfortunately, it didn't stay that way. Rapid global warming is back. But that means the goal is not to return to the artificially frigid temperatures of the 1960s or 1970s. The goal is to return to what it was just 3 years ago. I'm sure there are some older folks who think whatever the climate was when they were a child is what it should be. Reality doesn't care about your childhood. That wasn't not natural, that was the result of over 100 years of pollution causing global cooling. We've cleaned up pollution, and this is what we get.
Some people obsess over CO2 levels. Some thing it should be 200 parts per million (ppm). But ice cores from Greenland and Antarctica show the only time it was that low was during an ice age. During the very coldest years of the last 4 ice ages, CO2 got down to 180 ppm. However, during most of the ice ages it was 200 ppm. During interglacial periods it was always 300 ppm. The problem is CO2 levels have exceeded 400 ppm. That implies we have to do something. Not panic, not overreact, not claim we have to go cold-turkey on all fossil fuels. Just reduce a little. After all, 80 million years ago when dinosaurs roamed, CO2 was 1,000 ppm. And 500 million years ago, before dinosaurs evolved, CO2 was 7,000 ppm. That's 0.7%. When CO2 is 2,000 ppm it will smell stuffy. At 2% (20,000 ppm) it will give you a mild headache. At 10% (100,000 ppm) it's lethal. So increasing CO2 only affects global warming. And global warming until year 2000 was caused by removing pollution. Global warming until late 2014 was insignificant. Global warming since late 2014 is due to carbon emissions, but that's only 3 years.
I live in Canada. All electric cars won't survive a Canadian winter. Lithium-iron-phosphate batteries will freeze at -20°C. Winter here can get down to -40°C; real temperature, not wind chill. It only gets that cold at night, and only the coldest night of the year, but does happen. When I was a child it would happen a couple nights each winter. Then it became more rare. The last time was January 2005. But temperatures below -30°C happen several nights each winter. Each winter usually has a 2 week stretch where the daytime high does not get above -20°C (-4°F). In 2013 weather set a new record; not any record low, but the longest stretch with daytime temperatures below -20°C. It was 90 days (3 months). Any lithium ion battery that is lithium-iron-phosphate will be destroyed as soon as the battery freezes to -20°C. The cost of a new battery for an electric car costs as much as a used car. That means the car is destroyed. In the last 5 years there is a new type of lithium ion battery: lithium cobalt. It's more expensive because it uses cobalt instead of iron. For a battery of the same size, same weight, it provides the same charge so same range, and same power so same performance. The difference is it handles cold better. It will provide power to -30°C, and can be stored down to -40°C. But that means when winter temperature at night gets below -30°C, the car won't start. And temperature here does get down to -40°C once in a while; that will still destroy the battery. And although these batteries will provide power to -30°C, between -20°C and -30°C it's performance reduced. That means the closer the cold gets to -30°C, the shorter the range before your battery gives out.
The solution is nickel-metal-hydride batteries. A lithium ion battery provides 30% greater charge, so that much greater range, but nickel-metal-hydride can survive a Canadian winter. Car makers test vehicles with that battery in Thompson, a small mining town 8 hour drive straight north of Winnipeg. You think Winnipeg is cold? Thompson is colder. Notice the Toyota Prius uses nickel-metal-hydride, as do most hybrids.
Furthermore, how do you heat a car in winter? An electric heater? When temperature is below -30°C, that will consume so much power that an electric heater would drain your battery. With an electric car, no power means your car won't move. A hybrid car burns gasoline, so produces heat. When I was a teenager in the late 1970s, a typical car would give 15 miles per gallon. A Prius will give 54 miles per gallon, as will most hybrids. There are a couple cars on the market today that provide 100 miles per gallon. A hybrid with a nickel-metal-hydride battery is all you need. It won't completely eliminate fossil fuels, just reduce. That's good enough.
Plants are starves of CO2. Chloroplasts are enslaved cyanobacteria. They evolved when Earth had a 95% CO2 atmosphere. The enzyme of the first step of photosynthesis is sensitive to the ratio of O2:CO2. There's too much O2, the intermediate compound binds to O2 instead of CO2, so has to be recycled. That takes energy. Some weeds have evolved to concentrate CO2 in their leaf tissues, reducing this. Concentrating CO2 takes energy, but with Earth's current levels, overall it saves energy. Weeds that do this are called C4, because the compound used to concentrate CO2 has 4 carbon atoms. Plants that don't are called C3, because the intermediate compound in the first step of photosynthesis has 3 carbon atoms. Weeds have that same compound, but that's what they're called. Corn is a C4 plant, so grows as fast as weeds, but most food crops and trees are C3. The point is plants love CO2; from their perspective more CO2 is good. When there's more CO2, they grow faster. But unfortunately we're producing CO2 faster than they can remove it. Again this means we have to reduce the rate at which we emit CO2, but not completely stop it. Again that means reduce, not go cold-turkey.
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One thing is for sure, the climate is mind boggingly complex and affected in varying degrees by a wealth of factors: insolation, earth's spinning, probably electro magnetism, air flows, sea currents, sea temperature, reflectivity, freezing or melting of ice to name a few.
I agree about the point about industrial pollution possibly blocking sunlight. But the truth is we don't know for sure. As I have pointed out irrigation schemes around the world in v. hot countries must be adding billions, maybe trillions of tonnes of water vapour into the atmosphere every year.
I am fine with a precautionary approach of reducing CO2 emissions but I hate the arrogant certainty with which the AGW lobby make their pronouncements. Switching to natural gas makes a huge impact. On top of that solar and wind energy are becoming ever more price competitive with fossil fuels (and already winning out in some parts of the world. I believe within 30 years the fossil fuel industry will be dead effectively because solar plus storage will be so cheap.
Very long post. And I've had this argument so many times that I'm tired of it. Let me start by saying I used to believe in environmental stuff, but then "climate warriors" started claiming all fossil fuels must stay in the ground, they want to shut down all coal mines, all oil wells, all tar sands, even all natural gas. They want to shut down all oil pipelines. Cold turkey on all fossil fuels. That's just not possible!
The main problem is most people who believe anything on this issue fall into one of two camps: climate change deniers who try to claim climate change isn't happening, or climate warriors who claim the sky is falling. Of course the truth is somewhere in the middle.
Science documents global cooling from the beginning of the industrial revolution of 1855 until 1970. There was global warming during World War 1 and World War 2, but even between the wars there was global cooling. In the 1960s and 1970s, scientists were extremely worried about global cooling. They thought an interglacial period lasts 10,000 years, and it's been 11,000 years since the end of the last ice age, so we're over due for the next one. Some scientists seriously suggested dropping big thermonuclear bombs on the polls to halt global cooling. Luckily other scientists pointed out how much radioactive fallout that would cause, so no one did it. Then in 1979 one scientist published a paper about global warming. The entire science community at the time responded with "Are you nuts?!? Get with the program!!! We just spent two decades on the problem of global cooling!" But science is not a democracy, it doesn't matter how many agree with you, the only thing that matters is the data. He had data to back up is claims. They checked his data, doubled checked, triple checked, and checked again. It clearly showed global warming since 1970. Remember this was 1979, so global warming only existed for 9 years at that time. Data still showed global cooling form 1855 until 1970. Scientists were still skeptical, worried he "cherry picked" data that agrees with what he wanted to say, so checked outer sources. When that still agreed, they took new measurements. It all confirmed global warming.
But just as the entire establishment was skeptical about change then, an even broader establishment doesn't want to hear anything now.
Since year 2000, global warming has dramatically slowed. In fact it is a little faster than the pace of nature, but not much. From year 2000 until late 2014, the pace of global warming was so close to the pace of nature that you could say "good enough". In fact several scientists have published papers saying exactly that. But many scientists get funding to work on global warming, they don't want to jeopardize that funding.
Details: industry in 1855 burned coal to fire steam engines. Diesel-electric locomotives were developed from the early 1890s to late 19-teens, went into production in 1920. Some railroad companies replaced steam locomotives with diesel-electric throughout the 1920s, however here in Canada the CN railroad still used steam in the 1960s. A coal-burning steam power plant was built in downtown Winnipeg after a major storm brought down a power line from hydroelectric dams in northern Manitoba. That prevented blackouts, and hot water from condensed steam was piped to office buildings downtown. The last buildings stopped using it in the 1980s. Some cities started enacted pollution control in the 1880s, but the US federal government didn't start until 1928. At that time it was just "monitoring" in eastern cities. Throughout the 1950s pollution controls became more strict, and more so through the 1960s. In 1970 Congress re-wrote the "Clean Air Act". Notice global climate changed reversed from cooling to warming in 1970. Not a coincidence.
Smoke and soot from coal burning are "aerosols" that block sunlight. A dark cloud can block sunlight; ever feel a warm summer day, then a dark cloud passes overhead and you can feel a wave of cool pass over you as the shadow of that cloud? Coal smoke can do that. When industry began in 1855, smoke stacks just drew smoke out of the building, spewing soot over the immediate neighbourhood. People complained, so factories had to do something. They built taller smoke stacks, which spewed soot farther down-wind. People in that neighbourhood complained. So factory owners hired engineers who designed a tall smoke stack with a round cross-section instead of square, which would create an up-draft to draw smoke and soot into the clouds. They realized the soot would eventually fall when those clouds rained, but hoped it would be an uninhabited forest, and most importantly wherever it fell couldn't be trace back to them. However, it turned out these smoke stacks created such a good up-draft that it drew smoke and soot into the lower stratosphere. We live in the troposphere, the lower atmosphere close to the ground. Commercial jet airliners fly in the lower stratosphere, but in the 1800s there were no aircraft. The troposphere and stratosphere do not mix well, once something gets into the stratosphere, it's very difficult to get it out. It took decades to recover from 115 years of man-made global cooling.
As of year 1994, the temperature of the planet equalled what it was before the industrial revolution of 1855. Yes, that means all the global warming from 1970 to 1994 undid the man-made global cooling. But that doesn't take into account natural global warming. We're in an interglacial period, still warming out of the last ice age. Science has been able to reconstruct temperatures from 1550 to 1855; that's 305 years before the industrial revolution. There was very slow and steady natural global warming. If you assume the planet would have continued at that pace, then in year 2000 the temperature of the planet is what it would have been if humans hadn't messed with it. Notice what I just said. All the global warming that nature would have done from 1855 to year 2000, that's 145 years, was condensed to just 6 years, from 1994 to year 2000. That makes it look bad. But still, it doesn't change the fact that as of year 2000, the temperature was what it would have been if humans hadn't messed with it.
In year 2000, the rate of global warming dramatically slowed. Again, that's not coincidence. There's a deep ocean cycle that takes 1,000 years to completely one cycle. That will push the climate back to nature's schedule. So when we removed pollution, that contributed to restore the natural climate. From year 2000 until late 2014, the rate of global warming was almost the pace of nature. Again, I'm assuming the rate of global warming from 1550 to 1855 is the pace of nature. The rate from year 2000 to late 2014 was a little faster than nature, but good enough.
Soot in the lower stratosphere did a couple things. It dimmed sunlight causing global cooling, but also prevented radiant heat from escaping into space. That caused days to warm slowly, and nights to cool slowly. That changed weather to be mild, calm, predictable. Remember scientists tried to predict weather from the Renaissance, starting 1300. They weren't able to. That wasn't because they were stupid, scientists back then were just as smart as scientists today. Weather was far more extreme, chaotic, unpredictable. In the 20th century weather changed, became far more mild, consistent, predictable. Only then could science develop methods to predict weather. Now we have satellites and supercomputers to model the atmosphere of the entire planet, so the ability to deal with weather that is once again chaotic and extreme. But realize this extreme weather is not just due to global warming, it's also due to our blanket of soot in the stratosphere. Radiant heat at night can escape into space. I don't know about you, but I don't want the pollution back. But if we don't restore the blanket of soot in the atmosphere, we will continue to have extreme weather. This is our planet's natural weather.
According to NOAA, the number of tropical storms in the Atlantic has not increased. The proportion that intensify to become hurricanes has. Hurricanes are a giant convection current, carrying heat from the surface of the ocean to the top of the troposphere. Scientists have measured the temperature of the lower stratosphere since 1990. It has been dropping steadily. It spiked up when volcanoes erupted: Mount Pinatubo and that Icelandic volcano who's name I cannot pronounce. My ex is of Icelandic descent, so I have a bit of a mental block there. In both cases the temperature of the lower stratosphere increased, then plummeted. Not just to what was or what it would have been, it dropped significantly lower. Then stabilized, continued to cool at the same pace as before the eruption. Volcanic ash had caused warmed the stratosphere, then flushed out soot. This is mother nature cleaning up our mess. As of year 2010, the temperature of the lower stratosphere has completely stabilized, it isn't dropping any more. Air quality measurements state the only soot that remains in the lower stratosphere since 2010 is from jet aircraft exhaust. This confirms that global climate change is driven by removing pollution, not carbon emissions. But realize the consequence. The top of a hurricane is the top of the troposphere, where it touches the lower stratosphere. During hurricane season in the Caribbean and Gulf of Mexico, the lower stratosphere is -60°C. Hurricanes are convection currents, driven by temperature difference. Surface water has increased in temperature, while the lower stratosphere has dramatically cooled. That increased the temperature difference at both ends. That has increase the number and intensity of hurricanes. But again, this is our planet's natural weather. How many hurricanes existed in the first half of the 1800s? Were weather records even kept then?
I did say the temperature in year 2000 is what it would have been, and the pace of warming from then until late 2014 was so close to nature that it's good enough. Unfortunately, it didn't stay that way. Rapid global warming is back. But that means the goal is not to return to the artificially frigid temperatures of the 1960s or 1970s. The goal is to return to what it was just 3 years ago. I'm sure there are some older folks who think whatever the climate was when they were a child is what it should be. Reality doesn't care about your childhood. That wasn't not natural, that was the result of over 100 years of pollution causing global cooling. We've cleaned up pollution, and this is what we get.
Some people obsess over CO2 levels. Some thing it should be 200 parts per million (ppm). But ice cores from Greenland and Antarctica show the only time it was that low was during an ice age. During the very coldest years of the last 4 ice ages, CO2 got down to 180 ppm. However, during most of the ice ages it was 200 ppm. During interglacial periods it was always 300 ppm. The problem is CO2 levels have exceeded 400 ppm. That implies we have to do something. Not panic, not overreact, not claim we have to go cold-turkey on all fossil fuels. Just reduce a little. After all, 80 million years ago when dinosaurs roamed, CO2 was 1,000 ppm. And 500 million years ago, before dinosaurs evolved, CO2 was 7,000 ppm. That's 0.7%. When CO2 is 2,000 ppm it will smell stuffy. At 2% (20,000 ppm) it will give you a mild headache. At 10% (100,000 ppm) it's lethal. So increasing CO2 only affects global warming. And global warming until year 2000 was caused by removing pollution. Global warming until late 2014 was insignificant. Global warming since late 2014 is due to carbon emissions, but that's only 3 years.
I live in Canada. All electric cars won't survive a Canadian winter. Lithium-iron-phosphate batteries will freeze at -20°C. Winter here can get down to -40°C; real temperature, not wind chill. It only gets that cold at night, and only the coldest night of the year, but does happen. When I was a child it would happen a couple nights each winter. Then it became more rare. The last time was January 2005. But temperatures below -30°C happen several nights each winter. Each winter usually has a 2 week stretch where the daytime high does not get above -20°C (-4°F). In 2013 weather set a new record; not any record low, but the longest stretch with daytime temperatures below -20°C. It was 90 days (3 months). Any lithium ion battery that is lithium-iron-phosphate will be destroyed as soon as the battery freezes to -20°C. The cost of a new battery for an electric car costs as much as a used car. That means the car is destroyed. In the last 5 years there is a new type of lithium ion battery: lithium cobalt. It's more expensive because it uses cobalt instead of iron. For a battery of the same size, same weight, it provides the same charge so same range, and same power so same performance. The difference is it handles cold better. It will provide power to -30°C, and can be stored down to -40°C. But that means when winter temperature at night gets below -30°C, the car won't start. And temperature here does get down to -40°C once in a while; that will still destroy the battery. And although these batteries will provide power to -30°C, between -20°C and -30°C it's performance reduced. That means the closer the cold gets to -30°C, the shorter the range before your battery gives out.
The solution is nickel-metal-hydride batteries. A lithium ion battery provides 30% greater charge, so that much greater range, but nickel-metal-hydride can survive a Canadian winter. Car makers test vehicles with that battery in Thompson, a small mining town 8 hour drive straight north of Winnipeg. You think Winnipeg is cold? Thompson is colder. Notice the Toyota Prius uses nickel-metal-hydride, as do most hybrids.
Furthermore, how do you heat a car in winter? An electric heater? When temperature is below -30°C, that will consume so much power that an electric heater would drain your battery. With an electric car, no power means your car won't move. A hybrid car burns gasoline, so produces heat. When I was a teenager in the late 1970s, a typical car would give 15 miles per gallon. A Prius will give 54 miles per gallon, as will most hybrids. There are a couple cars on the market today that provide 100 miles per gallon. A hybrid with a nickel-metal-hydride battery is all you need. It won't completely eliminate fossil fuels, just reduce. That's good enough.
Plants are starves of CO2. Chloroplasts are enslaved cyanobacteria. They evolved when Earth had a 95% CO2 atmosphere. The enzyme of the first step of photosynthesis is sensitive to the ratio of O2:CO2. There's too much O2, the intermediate compound binds to O2 instead of CO2, so has to be recycled. That takes energy. Some weeds have evolved to concentrate CO2 in their leaf tissues, reducing this. Concentrating CO2 takes energy, but with Earth's current levels, overall it saves energy. Weeds that do this are called C4, because the compound used to concentrate CO2 has 4 carbon atoms. Plants that don't are called C3, because the intermediate compound in the first step of photosynthesis has 3 carbon atoms. Weeds have that same compound, but that's what they're called. Corn is a C4 plant, so grows as fast as weeds, but most food crops and trees are C3. The point is plants love CO2; from their perspective more CO2 is good. When there's more CO2, they grow faster. But unfortunately we're producing CO2 faster than they can remove it. Again this means we have to reduce the rate at which we emit CO2, but not completely stop it. Again that means reduce, not go cold-turkey.
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Climate is complicated enough that there is no one cause to pin change on, much to the chagrin of politicians. The Earth has had ice ages when atmospheric CO2 was low and when it was high, going all the way back to the start of oxygen content in the air around 2+ billion years ago. Over that interval, the sun has brightened by around 10-15% if the astrophysics guys are to be believed.
Continental placement, ocean circulation, insolation variations with solar constant and with orbital variations, changes in tectonics or at least heat in the core, changes in radioactive decay sources, changes in the basic density as well as the composition of the air, all of things (more besides) have been going on.
It is just as stupid to argue that we somehow "know" that humans are causing global warming, as it is to argue against it, from just one or two issues. We "know" (with certainty) nothing. We never have and we never will. There is no certainty. There are only models that seem to serve well, such as classical thermodynamics, and many others. Some of these seem to serve very well indeed, so it is foolish to bet against them.
As for climate change, the best model we have for the Pleistocene ice ages is orbital-change-induced variation of insolation on the northern hemisphere where most of the land area (with vegetation) is. It's a pretty good (not perfect) model of the last 3-4 million years, but it is not causal enough to explain the choice of, or the shift between, the controlling frequency of the 3 candidates: 100 kyr, 40 kyr, or 26 kyr.
That model says the giant glaciers should already be forming in eastern Canada, after a nominal 10 kyr interglacial. THAT is why scientists in the 1960's were thinking that global cooling was coming. I remember this quite well. No temperature records or emissions concerns were involved then. They had only started measuring atmospheric CO2 (the Keeling curve) in 1958, after all. The disparity between that orbital insolation cycles model, and what has been happening erratically ever since (interrupted-but-resuming warming), says something about this latest cycle is different, throwing the model off. No more certain than that!
The most obvious difference is us and our technological civilization. Something about us is disturbing the balance. Is it our CO2 emissions? Maybe, these have been steadily growing exponentially since about 1750, until very, very recently. Is it CH4 and CO2 emissions from our agricultural practices? Maybe. These have been operating for 10 kyr, but got industrialized into mass production over about the last century. Is it our other pollution? Could be, we already know we have caused ozone holes, acid rain, and many of our cities have heat plumes that disrupt local weather rain patterns. Could it be something else? Sure, but what?
Is there any certainty to any of this? No. There never will be, certainly not on a time scale useful for taking corrective action, if such should be found necessary.
But there are suggestive things that we do know with good probability. Before there was modern climate science, there were "natural science" observations of glacial retreat, starting in the 19th century. That hasn't changed, the ice is still retreating, accelerated, if anything. Where's there's ice melting, there's the heat to cause it. That's just well-accepted physics. That extra heat has to be coming from somewhere. And most of our energetic activities create heat, one way or another.
Now, other well-accepted physics says the "greenhouse effect" is quite real. Gases that absorb more infrared radiation instead of freely transmitting it will act as a blanket, so that surfaces within that blanket must be at higher temperatures to radiate effectively through it. And well-accepted physics says that energy is conserved: whatever system you want to define must balance input with output in order to remain steady state, If imbalanced, that state will change. Some gases transmit less infrared: CO2, CH4, and H2O being among the larger such actors, as can be measured in the laboratory. These happen to be our most voluminous emissions. Certainty? No. Probability? Yes, rather high actually.
Water is the oddball. It changes phase and also reflects visible insolation when condensed. Is it more cause or more effect? We don't know. We're not gonna know, not in time to do anything.
OK, say we agree that we emit too much CO2. Should we stop all fossil fuel use instantly? No, that would kill thousands of people and utterly crash our economies and our civilization. Should we favor cleaner technologies over dirtier ones? Probably. Natural gas has been displacing coal in power plants, being much cheaper and more available, with shale fracking technology. Pound for pound, it reduces CO2 emissions, that we have measured. Is it enough? No, the Keeling curve is still going up.
Now, wind and solar are making some inroads into power generation, since the installation prices have come down enough to be competitive in some way. Perhaps some extra incentives would be beneficial to speed that process up. Seems logical enough. But there are limits: the intermittency of these sources seems to indicate that they should be no more than roughly 20% of the mix until the energy storage problem is licked. It ain't licked yet. Maybe that is something we should be attempting with more resources and effort.
And as RobertDyck indicated, battery cars don't work in the cold northlands. Neither does 100% biodiesel (it freezes too easily). As I said, there's limits. Which really means more ice will melt and seas will rise. Maybe not what the climate scientists predict, but even half a meter over a few years is quite the disaster to cope with. More than enough.
How sure are we this really will happen? Seems rather probable, since the ice melt observations and the climate model calculations point to the same end. Two independent sources saying the same result! Probability seems very high. Certainty? No, never.
Seems to me the proper public policy is to favor a "best practical speed" approach to cleaner energy sources, and to favoring the renewables within those practical deployment limitations, while devoting significant resources to solving the energy storage problem. Two other solutions we also need are efficient transmission over the grid (we lose 50% of our electricity to I^2R losses), and a new version of nuclear that doesn't create such a noxious waste stream (that would be thorium-based fission.)
Those are the things that make the most sense to me. The thing that makes the least sense to me is to make this issue a matter of political belief, where the two sides exaggerate everything all out of proportion, and far beyond the bounds of whatever facts we can know. Of the two sides, I find the "conservatives" the more egregious by denying more science, but that is just my opinion. The rest stands as more fact-based. Facts in the sense of what can be known with high probability. There is no certainty.
GW
Last edited by GW Johnson (2017-10-16 11:04:40)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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Of course we had the Medieval warming period as well - the pre-industrial warming - which allowed the Vikings to successfully settle Greenland for a while. Supposedly as a result of increased insolation and reduced volcanic activity, plus changes in ocean currents...well maybe. I can't any of those three are easy to measure at this distance of time.
Climate is complicated enough that there is no one cause to pin change on, much to the chagrin of politicians. The Earth has had ice ages when atmospheric CO2 was low and when it was high, going all the way back to the start of oxygen content in the air around 2+ billion years ago. Over that interval, the sun has brightened by around 10-15% if the astrophysics guys are to be believed.
Continental placement, ocean circulation, insolation variations with solar constant and with orbital variations, changes in tectonics or at least heat in the core, changes in radioactive decay sources, changes in the basic density as well as the composition of the air, all of things (more besides) have been going on.
It is just as stupid to argue that we somehow "know" that humans are causing global warming, as it is to argue against it, from just one or two issues. We "know" (with certainty) nothing. We never have and we never will. There is no certainty. There are only models that seem to serve well, such as classical thermodynamics, and many others. Some of these seem to serve very well indeed, so it is foolish to bet against them.
As for climate change, the best model we have for the Pleistocene ice ages is orbital-change-induced variation of insolation on the northern hemisphere where most of the land area (with vegetation) is. It's a pretty good (not perfect) model of the last 3-4 million years, but it is not causal enough to explain the choice of, or the shift between, the controlling frequency of the 3 candidates: 100 kyr, 40 kyr, or 26 kyr.
That models says the giant glaciers should already be forming in eastern Canada, after a nominal 10 kyr interglacial. THAT is why scientists in the 1960's were think global cooling was coming. I remember this quite well. The disparity between that model and what has been happening erratically ever since (interrupted-but-resuming warming) says something in this cycle is different, throwing the model off.
That difference is us and our technological civilization. Something about us is disturbing the balance. Is it CO2 emissions? Maybe, these have been steadily growing exponentially since about 1750, until very recently. Is it CH4 and CO2 emissions from our agricultural practices? Maybe, these have been operating for 10 kyr, bt got industrialized into mass production over about the last century. Is it our other pollution? Could be, we already know we have caused ozone holes, acid rain, and many of our cities have heat plumes that disrupt local weather rain patterns.
Is there any certainty to any of this? No. There never will be, certainly not on a time scale useful for taking corrective action, if such should be found necessary.
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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Compared to the glaciation versus interglacials of the Pleistocene ice ages, things like the Medieval Warm period versus "the little ice age" are tiny small change. Marbles compared to house-sized boulders. You can see the effect of the marbles as the Vikings in Greenland, and the famines produced by the consecutive cold summers and harsh winters of the little ice age. Now imagine what full deglaciation or full reglaciation would do to our planetwide civilization. Doing nothing to forestall the fairly-reliably predictable disaster is not an option. How we stay closer to the status quo climate-wise is the only option we have. If that. Mother nature may have other ideas. While we definitely can affect her, she is still more powerful than we are.
GW
Last edited by GW Johnson (2017-10-16 11:14:45)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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Again looking at data from ice cores from Greenland and Antarctica. As snow falls, the snow at these locations just don't melt. The snow accumulates, gets crushed to form ice. Air trapped between snow flakes gets trapped as bubbles in the ice. This gives us a sample of Earth's atmosphere, year by year, going back thousands of years. Some ice cores go back 400,000 years, a few go back 450,000 years. The first lesson is interglacial periods do not last 10,000 years. Scientists of the 1960s and 1970s were wrong. The last 3 interglacial periods lasted 20,000 years each. The one 4 interglacial periods ago lasted 30,000 years.
Ice ages occur on average every 100,000 years. But there's variation. That's if you measure from the beginning of one ice age to the beginning of the next. Or the end of one to the end of the next. Pick a point in the cycle, it's 100,000 years to the same point in the next cycle. Interglacial periods were 125,000 years ago, 225,000 years ago, 325,000 years ago, and 400,000 years ago. That's because the last ice age lasted 25,000 years longer than usual. The two ice ages before that were normal: 80,000 years of ice plus 20,000 years of warm "interglacial" period. The ice age before that was 25,000 years shorter than usual.
When you look at the pattern of temperatures, the last 3 interglacial periods were very consistent. Their peak temperature was 6°C above the pre-industrial temperature. So when politicians debated in Paris whether to limit global warming to 2°C or 1.5°C above the pre-industrial temperature, I had to laugh. What makes them think they're in control? What makes them think they can do that? Nature will raise the temperature far above that. Or does someone claim we had cars and coal burning power plants 325,000 years ago? However, the good news is if we do follow that same pattern, the peak of 6°C above the pre-industrial temperature will not arrive for another 2,000 years. In geological terms that very near. In terms of a human life span, that's not close at all.
However, if you look more closely, the pattern of global warming from the end of the ice age 11,000 years ago until the beginning of the industrial revolution of 1855 more closely followed the pattern 4 interglacial periods ago. That's 400,000 years ago. That interglacial period had a peak temperature of only 3°C above the pre-industrial temperature. And that interglacial period lasted 30,000 years. That's what we were doing before humans messed with it. It warmed more slowly than usual, and cooled more slowly, resulting in more years before the next ice age. Messing with the climate could cause the pattern to more closely match the last 3; that means rapid global warming followed by rapid cooling. You could argue we should return to the natural pattern, because that would limit global warming and delay the next ice age. But what is the impact of measures you propose?
Here in Canada, environmental activists argue to shut down all pipelines. The Prime Minister is trying to play both sides. He campaigned that he will impose a carbon tax, and is currently pressuring provincial governments to work with him to do that. At the same time he approved new oil pipelines: expansion of Line 3 from the Alberta oil patch to Chicago, twinning the Trans-Mountain pipeline to Vancouver harbour, and the "Energy East" project to convert an existing natural gas pipeline to oil. He disapproved the Northern Gateway pipeline because that would have gone through native land that has never been ceded to the crown. We certainly don't want to take more land from aboriginal people. And it looks like the Keystone XL pipeline will proceed. "Energy East" has been cancelled for economic reasons, but the rest are proceeding. Environmentalists who voted for him are now unhappy.
And Line 9 was built during the administration of Pierre Trudeau, father of our current Prime Minister. That pipeline was built to deliver Alberta oil to Ontario and Quebec. It connects to Line 3 outside Chicago, extends northeast crossing into Canada just north of Detroit, then connecting to all refineries in southern Ontario, ended outside Montreal. A spur of that pipeline extends north up Michigan to Sault St. Marie, Michigan, then under the river to Sault St. Marie Ontario. When Prime Brian Mulroney was elected, he shut down that pipeline. The owner of the pipeline couldn't leave it sitting idle after investing millions of dollars, so built an extension from Montreal to Portland Maine, then reversed the flow. It was used to deliver Middle East oil to the American midwest: Chicago/Detroit area. During the election of 2006, I proposed reversing it again, using it for what it was built for. The administration of Prime Minister Stephen Harper did so. Now it delivers Alberta oil to Ontario and Quebec. Of course that means the midwest is cut off from Middle East oil. They have to use a combination of American oil, and Canadian oil. But with fracking, there's a lot more domestic American oil now. Americans who want to stop importing Middle East oil are happy. Canadians in Ontario and Quebec are happy because Alberta oil is now less expensive than Middle East oil. But environmentalist are not happy.
My primary concern is the *expletive* carbon tax! I live in Winnipeg, in the province of Manitoba. Here electrical power is generated 100% by hydro-electric dams and windmills. We have 100% green, environmentally friendly, sustainable power generation. And the Manitoba Hydro utility uses biodiesel for their vehicles. They use 100% biodiesel in summer, but have to blend petroleum diesel when temperatures get cold. When it's so cold that biodiesel gels, they have to add enough petroleum diesel to keep it flowing through fuel lines. During the coldest months of winter, they do have to use pure petroleum diesel. That utility also subsidizes home owners to improve insulation, offers a loan to replace your furnace with a high efficiency one, offers a "rent to buy" plan for a new high efficiency furnace. They even had people walk door-to-door giving away low-flow shower heads, pipe insulation, and pamphlets on energy conservation. We do everything right now. There's nothing a carbon tax could do that we aren't doing already. You don't penalize those who do things right! A carbon tax here would be just a cash grab! Luckily the Premier of our province is fighting it.
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I have always favoured a precautionary approach of trying to minimise human impact on the global ecosystem and keep to historic atmospheric parameters - but that doesn't mean you have to accept the AGW propaganda which asserts we know various things as fact when we don't.
Compared to the glaciation versus interglacials of the Pleistocene ice ages, things like the Medieval Warm period versus "the little ice age" are tiny small change. Marbles compared to house-sized boulders. You can see the effect of the marbles as the Vikings in Greenland, and the famines produced by the consecutive cold summers and harsh winters of the little ice age. Now imagine what full deglaciation or full reglaciation would do to our planetwide civilization. Doing nothing to forestall the fairly-reliably predictable disaster is not an option. How we stay closer to the status quo climate-wise is the only option we have. If that. Mother nature may have other ideas. While we definitely can affect her, she is still more powerful than we are.
GW
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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Actually science (as a body of knowledge and a method of acquiring and assessing knowledge) knows nothing as fact. It only has hypotheses and theories that have not been disproven by repeatable experiment and/or observation.
The more a theory is tested, the more chance there is that it does represent fact, but it only clocks up a probability of a string of 9s at best. It can never get to 100%. That marginal probability of theory being wrong enables science to move forward, but it also enables charlatans, the confused, the possessors of closed minds and those with investment (emotional or real) in them to continue to promote theories which have not been tested and scrutinised. This includes climate change.
The theory of manmade climate change, unfortunately, has attached to it what looks a lot like a gravy train. This gives ammunition to it's detractors and distracts from the observational and experimental support, which has not found the theory incorrect as far as I can tell.
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I would trust the researchers more if they didn't have a vested interest in getting a particular result.
The whole scientific establishment needs to be torn down and rebuilt. It's rotten.
"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony
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Actually science (as a body of knowledge and a method of acquiring and assessing knowledge) knows nothing as fact. It only has hypotheses and theories that have not been disproven by repeatable experiment and/or observation.
The theory of manmade climate change, unfortunately, has attached to it what looks a lot like a gravy train.
A good example is the science theory that the Earth is round and not flat. What a gravy train for the transportation industry!
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The Earth being round is an observation.
Similarly, the temperature of the Earth's atmosphere, and any warming or cooling that is occurring, is an observation. Depending on the quality of the measurement, it may or may not be an accurate one. The idea that it is warming due to increased CO2 levels is a *theory*, which may or may not be supported by the data. The predictions of the temperature under different levels of CO2 are based on *models*, which have to be checked and verified against empirical data.
"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony
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