Climate and atmosphere mass - of the terraformed worlds

karov · 2004-08-01 09:43:06

The mass of the atmosphere defines its thermal and mechanical inertion. As a result significantly are smoothen the movements as well the temperature contrasts within it with the increase of its mass. As bigger is the mass, as stronger are the atmosphere`s abilities as thermo-carrier, able to transfer heat from the warmed areas toward the cooled and thus partially to equalize the horizontal temperature differences. If the atmosphere masses are not too small or too big compared with the ?arth`s ( say within the range of two orders of magnitude in the two directions ) the mean speed of the wind in the troposphere, as well the typical horizontal differences in the temperature ( including the difference between the equator and the poles) is inversely proportional to the square root of the planetary atmosphere mass. Of course: the scalehight in lower gravity, the effects of the Coriolis force if the body rotates fast enough, the topography, the shear amount of illumination, spectra of the incoming light, the greenhousing... all they impose deviations of this general thermodynamical consequence, but very real is the tendency toward growing stronger the winds and increasing of the temperatural differences with decreasing the mass of the atmosphere. The coefficient of increase/decrease of the atmosphere dynamics interacts with the effects due to the absolute size of the terraformed planetary-mass body.

Hence:
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Mars has a third earth`s gravity and total area. The ~1/3 G needs three times more air weight to produce 1 bar. These three times higher are situated on three times smaller surface - so the atmosphere of the terraformed Mars equals the Earth`s in initial thermodynamics. The linear dimensions of Mars are ~1/2 the Earths with almost equal sol lenght, and bigger Coriolis force, so very earth-like overall climatic picture should be observed, better smoothen cause of the bigger proximity equator-poles, but the coriolis effect will more effectivelly divide the new atmosphere in cells... If 0.3 bars are chosen than generally with 1/3 total atmosphere mass we should expect ( puting asside the action of the rest of the important factors ) almost three times stronger winds and three times bigger differences in the temperature of the insolated vs. cooled areas.
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The Moon: 1/6th gravity and 1/16th surface area. The mass of projected 1 bar terraformed lunar atmosphere is 6/16th the earth`s. That means the winds will be 60% faster, and the temperature differences 60% bigger than on earth, calculated on mass basis. The shear lunar size is ~4 times smaller than earth`s. So it occurs that, perhubs the heat will be 4/1.6 times more evenly distributed on-surface than here.
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Venus: If the Atitarev design is chosen, with 3 bars of ambient presure at the ground -- than ~3 times slower winds and ~3 times smaller differences in the temperature would occur. No practical Coriolis effect. Thus, perhubs, quite pleasant and moderate tempreature ( over the freezing point of water at ~3 bars ) might be kept globewide - day/night; equator/poles...

This thermodynamical property by mass of the planetary earth-like atmospheres gives us good orientation point.

Please point me links and sources about the other factors` ( mainly the planetary circumference, the atmosphere scalehight and the axial rotation rate) action over the heat distribution, hence temperature differences on terraformed planets.
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Interesting is also the mode of action of the primary gas in concern with the biosphere and the greenhousing ( putting asside the water ) -- the CO2, which partial pressure could be manipulated in broader limits under the poisonous level via traditional industrial and biosperic means, without to depend on billions of years long geological cycles:

Now we have 0.03% CO2 in the earth`s atmosphere. In the end of XIXth century Svanthe Arenius pointed out that the increase of the CO2 amount in the atmosphere raises the total average temperature in all areas, and vice versa. But, the increase/decrease of the CO2 quantities influence in different manner the different latitudes - minimal change at the equator and the latitude where the change reaches its maximum is as higher as bigger is the change in the CO2 content. If the total quantity of CO2 is diminished to 2/3ths the modern level - maximal cooling ( with ~3 K ) occurs at 40 degrees latitude; if the CO2 level is doubled, than maximal increase of the temperture is observed on 60 degrees latitude ( with +6 K ). At the poles the impact of varying CO2 level slowly diminishes. It is weaker during the summer and stronger in the winter. If the change of the CO2 level is in geometric progression, the temperature change is aritmethical... I think in the exact CO2 earth`s mechanism is involved also the coriolic cells` effect, but even on slower rotating bodies we could let the CO2 to be at certain level in order to arrange the prefered climate in the chosen latitudes...

Is someone of you able to make or to point some modeling software, taking into account the general behavior and properties of an earth-like composition atmosphere at sea-level standart presure in differing: gravity (i.e. troposphere hight), axial rotation, CO2 levels, water content, planetary circumference...

atitarev · 2004-08-01 21:04:00

Hi Georgi,

Interesting topic. Pity, I am too busy these days.

I didn't have any luck with my search for Venus climate simulation pages. Although, I found this:

http://www.users.globalnet.co.uk/~mfogg/simul.htm]The Terraforming Simulator Project

http://www.users.globalnet.co.uk/~mfogg … m.html]The Actual Simulator You'll need Java run-time environment.

This simulation was used to calculate what variables should be achieved to terraform Mars (not new) but I'm posting in case someone hasn't seen it.

Agree with all the points, only with the Lunar climate - not sure - if we get the coriolis effect because of the slow rotation then the winds will go East-West-East and the poles remain cold but the temperature will spread evenly along the latitudes.

As for the Venus terraforming - could you help to prepare a summary that I could send for discussion/comments to a couple of people - Gerald Nordley, Paul Birch and people who contributed to the Venus discussion. The former (G.N.) replied to me and we had a discussion about Mercury terraformation. The latter (P.B.) wasn't very enthusiastic but we may try to get his help anyway. If we get some support on the key points the paper will have much better value. I mean, this hasn't been discussed in details in any page I saw - non-traditional terraformation of Venus - no spinning up, no permanent shades (after terraforming not during!), higher pressure, hotter and wetter climate but here we are - a realistic method. The major big expenditures will be on building chimneys, shuttles to remove gas, magnetic fields, temporary sun shields, technology to bring water and oxygen, clean the remaining 3 bars of the atmosphere.

How good is it going to be remains to be proved and discussed - it's all based on the assertion that Venus is still in the habitable thermal zone (180% of the Earth) and the correct balance of atmosphere-hydrosphere composition and amount will give us a tolerable climate - different from Earth but the one life could adjust to - the 3 bars atmosphere required to give more albedo, keep the temperatures even on the lit and the dark side (having 56 Earth days long days and nights), better radiation protection combined with installed magnetic fields.

Another point on the topic is that having a larger (taller) mass of the atmosphere on the smaller bodies including Mars and the Moon makes almost all elevation levels habitable! Think about it: if Martian atmosphere has to be 3 times higher than Earth to achieve one bar - there won't be much difference in pressure between 0 sea level and the top of the largest volcanoes. Olympus Mons could even have a huge lake in its caldera. (I can foresee angry comments from the Reds - leave Olympus Mons alone!)

karov · 2004-08-01 22:37:39

Hi Anatolii,

Thank you very much for the simulator. It would be just perfect if similar is available, but with more variables encompasing things like - diameter, rotational rate, surface gravity of the planets, spectrum of the illumination. Such way one could check his ideas for all distinct-surface (ocean/land) selfrounded bodies within the Solar system, and indeed others non-present here examples. We have to outline the bottom boundaries of the classical open-skyed terraformation. The upper limit is the lack of distinct surface in the gas giants, obviously and needs Birch`s tech for colonization...

In the topic about terraforming the smallest planets I tried to 'prove' that bodies with even 1% earth`s surface gravity could be aired and via 'cryogenic' works in the two key atmosphere layers to be kept such earth-standard atmosphere around so looselly pulling planemos for billions of years. To extrapolate the global climatological patterns of the terraformed Charons or Vestas, where the troposphere hight is comparable with their radius and the top atmosphere layers have to be kept in place via non-gravitational ( plasmic-magnitospheric? ) means we need a little more sophisticated simulator.

Note: I think that when the bulk of the planemo atmosphere is within its gravitational sphere of influence -- this makes the lowest surface gravity boundary for terraformability. The leaks through the gravitational treshold could be prevented by 'merged' magnitospheres which not only to deflect the solar wind`s or radiation belt`s picking-up ions, but also to channel back-in the trying to escape atmospheric ions...

About the global climatological mass-factor influence I agree that I couldn`t determine ( mainly due to general lack of knowledge ) exact temperature distribution parameters on any body. But this law is very general , based on very fundamental scientific principles, so the other variables would indeed 'add colour' in the overall picture underlined with this basic thermodynamics` consequences... I`m highly inclined to accept your oppinion on the terMoon climate -- indeed stating I was actually asking questions, and now I`m closer to an answer.

I`ll participate in working out paper about Venusian terraforming in the discussed 2-3 bars, non-spining , non-sunshielding model. About Mr.Birch - I also exchanged several letters with him ( he kindly sent me a scanned copy of "A Visit to Suprajupiter") , where he expressed his scepticity about the stated by me "osteofixation" as an livable parallel tech of the centrtifuges and the cradles for preventing the bone-loss in micro- and low-g environments. It occurs that P.Birch is quite 1G-conservative, and doesn`t agrees with the idea that non-modified genetically standard humans could conquer all the spaces from 0 to >1G. May be I`m highly optimistic towards the development success in the cellular sircuitry re-regulation, but having in mind the strong market demand pressure for such tech in the future, I hope that the trans-G roamers will have the good at time... P.Birch could point us various and powerfull means of transporting interplanetary of many gigatones of necessary for terraformation stuff. The G.Nordley article was very usefull for me to confirm some of my older whims, so I`ll be glad if he is involved in the paper production.

BTW, please get me acquiant with the Nordley`s comments about the terraforming of Mercury in the Mercury topic in this forum!!!

For the projected paper as co-autor I couldn`t contribute as much, but I can collect and re-think some of my posted here ideas, mainly about the sourses of material and the industrial vs. photosynthesis arguments.

About the practical pan-habitability of teraformed bodies with lesser surface gravity and hence, deeper atmospheres -- I pointed this by stating that the Moon is actually flat in meteorlogical sense. 1 Bar on Moon means troposophere brethable to ~70-80 km in hight!!!

Waiting for further points in the paper work agenda.

atitarev · 2004-08-02 17:56:41

Hi Georgi,

I posted G. Nordley's comment on June 27 in Mercury's thread and you read it.

Sorry for being slow with the paper work - it's a busy time for me with work and family commitments but I'm planning to start working on it anyway. If a draught is turned down by scientists at the start - there's no point in going further anyway - we'll look at other options.

P.S. You probably should spell it as Ghéorghy or Guéorgui to show the pronunciation - Georgie is a female name in English, by the way. My name is spelt with one "i" in English, although it's spelt Àíàòîëèé (switch to Cyrillic-Windows encoding) in Russian.

karov · 2004-08-03 08:31:47

OK. I`m bussy these weeks, too.

The ability ogf a world to retain atmosphere depends on the termodinamics of the troposphere and exobase, but in most case artificial magnetosphere should be deployed. Regarding the magnetosphere -- it could be designed in such manner than the ascending to escape ions to 'climb' against the vectors of the mag-force and thus very low-G worlds to be able to hold air cover for billions of years... That highly depends on the radius of the planemo`s Hill sphere - actually the sphere in which the gravity pull of the planet/moon dominates the objects movements over the gravitational interaction of the Sun or the major planet...

In "Terraformig smallest planets" I want to post a table which I made with all the PLANEtary Mass Objects in the Solar system (except some of the transneptunians with proper characteristics and of course the plenty of non-discovered, yet), with: diameter, mass, surface gravity in m/s2 and gees, projected troposphere hight, Hill sphere diameter, surface area...

Anatolii, please tell me how exactly to post it as a picture.

karov · 2004-08-03 08:38:03

Anatolii, please when you are ready with you paper about "Atitarev desing terraformed Venus" -- send it to me - if you prefer as a personal note - I promise to give comments and even to participate as co-autor of the final product if of course you let me in. Did you regard it as something that can be published in some magazine on paper?

BTW, I think the exact spelling of the pronunciation of my first name is not so important. All english speakers tend to george-ise it, so...

atitarev · 2004-08-03 14:21:39

We'll see how good it gets, Georgi - too early to talk about publishing in a magazine but who knows... It's a good idea.

To post an image here - you need to have that image somewhere on a website - you can find free hosts and publish you web pages and images there. In this forum, when you post you'll see the "image" button.

karov · 2004-08-06 16:21:42

We'll see how good it gets, Georgi - too early to talk about publishing in a magazine but who knows... It's a good idea.

We have to try. On paper it would last longer. I think it will get very well.

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#1 2004-08-01 09:43:06

Re: Climate and atmosphere mass - of the terraformed worlds

#2 2004-08-01 21:04:00

Re: Climate and atmosphere mass - of the terraformed worlds

#3 2004-08-01 22:37:39

Re: Climate and atmosphere mass - of the terraformed worlds

#4 2004-08-02 17:56:41

Re: Climate and atmosphere mass - of the terraformed worlds

#5 2004-08-03 08:31:47

Re: Climate and atmosphere mass - of the terraformed worlds

#6 2004-08-03 08:38:03

Re: Climate and atmosphere mass - of the terraformed worlds

#7 2004-08-03 14:21:39

Re: Climate and atmosphere mass - of the terraformed worlds

#8 2004-08-06 16:21:42

Re: Climate and atmosphere mass - of the terraformed worlds

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