Nuclear Winter on Venus

[sernpiat]

What's the prospect of cooling the planet Venus through Nuclear Winter?

 

[sernpiat]

I see.. thanks for the reply.

 

[Maddad]

The clouds of Venus actually work to hold thermal energy in. The planet would be colder without them. Sunlight's wavelengths are transparent to the clouds, so they penetrate to the surface. The ground re-radiates this energy at longer wavelengths that are opaque to the clouds, so the infrared radiation stays inside the cloud cover and warms the planet. Strip the clouds away and the ground would radiate it's heat off into space.

 

[slayera]

An theories on how much cooler the planet would be with no clouds or even less cover than now?<br />Are the clouds building, decaying, or do they maintain?

 

[sernpiat]

If there is some way we can remove those clouds, Venus is probably easier to work on than Mars... or is it still not?<br /><br /><br />The clouds are essentially sulphuric acid. What's the prospect of the venus's dusts thrown sky high reacting with them, thereby reducing the cloud?<br />

 

[alokmohan]

Why call it nuclear?

 

[nacnud]

Because a large nuclear bomb strike (on Earth) could kick up loads of dust and block the sun, hence nuclear winter.

 

[Maddad]

Venus is 70% of the distance to the Sun as compared to the Earth, so it gets twice the sunlight as compared to Earth. Without the cloud cover, polar latitudes might be livable. Trying to find the winter hemisphere will not help you because the inclination of Venus' orbit is only 3 degrees as compared to Earth's 23 degrees. There would not be much seasonality. Another consideration would be open bodies of water. If the thick atmosphere goes away by percipitating into water then you might see some significant thermal leveling. Offhand, I do not know the composition of Venus' atmosphere. I thought it was mostly carbon dioxide, but the exact numbers would make a difference.

 

[silylene old]

<i>Because a large nuclear bomb strike (on Earth) could kick up loads of dust and block the sun, hence nuclear winter.</i><br /><br />Most of the nuclear winter dust comes from the firestorms of burning forests, cities, refineries and oil wells....not the blasts themselves. Since Venus has very few of these features, it's unlikely a Venusian nuclear winter would be very effective. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[newtonian]

maddad- Good post. The mostly CO2 atmosphere of Venus is very thick indeed.<br /><br />silylene- agreed.<br /><br /><br />You all - Want to cool Venus? Not so easy. <br /><br />First of all, the main content of Venus’ greenhouse atmosphere is CO2.<br /><br /> On earth the early CO2 atmosphere has been locked up in earth’s crust mostly in the form of carbonates, mostly by the geologic carbon cycle, some also by the biologic carbon cycle. Interestingly, if you calculate the amount of CO2 that is in earth’s carbonates, you will find it is similar to the amount of CO2 in Venus’ atmosphere.<br /><br />However, in order to lock up CO2 by the geologic carbon cycle you would need oceans, as were on early earth (Genesis 1:2). <br /><br />Even with the immense atmospheric pressure on Venus’ surface, the surface is still too hot to maintain liquid water oceans. <br /><br />Actually, early earth was similar to Venus. However, while Venus experienced a runaway greenhouse effect, earth was fine-tuned to allow our very unlikely atmospheric and surface conditions.<br /><br />Earth may have had a number of condensation catastrophes, which were part of cycles involving the cooling of earth’s crust and the lowering of atmospheric pressure on earth’s surface. The key is that earth cooled and atmospheric as well as very high altitude water vapor condensed on the surface, while Venus heated up and its oceans evaporated into the atmosphere. <br /><br />BTW - hotter surface temperatures would also release CO2 from carbonates. This is one reason CO2 is one of the gasses in volcanic outgassing on earth.<br /><br />It is not humanly possible to reverse Venus’ greenhouse effect. It is difficult enough for us to repair the damage we have done to earth’s environment.<br /><br />Of course, if our sun goes to red giant, and Venus’ orbit recedes due to lower solar mass, then our sun may strip Venus of its toxic atmosphere (e.g., it also has sulphuric acid as noted by others), and then Venus could indeed co

 

[silylene old]

would be rather hard to "burn things" in a venusian atmosphere of only 2% oxygen anyways. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[sernpiat]

I had the delusion that it will be easier to colonize Venus than Mars... dump our nuclear warheads over Venus, kick up enough the dust to block out sun light for half a century, return later to find a cooler planet which is more hospitable to life...<br /><br />Newtonian: You mentioned that *earth was fine-tuned to allow our very unlikely atmospheric and suface conditions*. I guess it is really a miracle that Earth actually made it. (and yet we are posioning it)<br /><br />Am i right to think that it is easier to warm up a planet than to cool it? Does Mars has enough carbonate to liberate enough CO2 to warm itself up? <br /><br />I just fear that Mars may not have enough gravity to hold that additional gas.<br /><br />Biosphere with compressed CO2 may be a better alternative... localized greenhouse .. <br /><br /><br />

 

[lowendfreq]

quick call Brad Guth <br />http://guthvenus.tripod.com/

 

[alokmohan]

It is easy to adjust to lower gravity.

 

[Maddad]

crazyeddie<br />"<font color="yellow">There is no significant amounts of water anywhere on the planet.</font><br />Water though is simply hydrogen and oxygen. Venus has plenty of both, just as Earth did in the first billion years of the solar system. That oxygen is bound to rocks. Chemically re-arrange it and you get that missing water.<br /><br />sernpiat<br />"<font color="yellow">Am i right to think that it is easier to warm up a planet than to cool it? Does Mars has enough carbonate to liberate enough CO2 to warm itself up? I just fear that Mars may not have enough gravity to hold that additional gas.</font><br />Mars has a low mass, about 10% that of Earth, and therefore only about 40% the gravity of Earth. It also has almost no magnetic field, which on Earth deflects the solar wind. On Mars this unimpeeded solar wind kicks molecules in the outer atmosphere away into space. Both the higer gravity and the magnetic field conspire to help Earth hold onto its atmosphere. As a consequence, Earth's atmosphere today, 4,500 million years after creation, is 200 times denser than that of Mars. If Mars did get an atmosphere, it would quickly lose it again.<br /><br />However, quickly is a relative word. Since Human beings first stopped following herds of migrating animals and settled into places where they stayed all year around, civilization has been around less than 0.01 million years. If you created an atmosphere for Mars that you wanted to last as long as all of human civilization before us, then you just need that atmosphere to last a half millionth as long as the previous atmosphere.<br /><br />Put another way, if we bring an atmosphere to Mars, it will remain there as long as we do.

 

[newtonian]

maddad - good post. It is theorized that Venus had much more water, which through photo-dissociation (=photolysis) was separated into hydrogen and oxygen, hydrogen escaping and oxygen chemically bonding to other elements.<br /><br />Ditto earth, but to a lesser extent (thankfully).<br /><br />However, there is water in Venus' atmosphere, according to this reference concerning Venus:<br /><br />The proportion of water vapor in the atmosphere is now only 0.005%, but even so it accounts for about 25% of the present Venutian greenhouse effect. The other major contributors are carbon dioxide, sulphur dioxide and clouds and haze."- "The World of Science," 1991, by Andromeda Oxford Ltd. (distributed by Britannica), Volume 7 "The Universe," Page 56 under "Venus."<br /><br />Remember that is actually a large amount of water - the percentage is lowered due to the the vastly thicker atmosphere of Venus compared to earth (e.g. the much greater mass of CO2 in the Venutian atmosphere).<br /><br />Anyone have a more recent update on H2O percentage on Venus?

 

[Maddad]

I'm too tired to do it tonight, but you could use that information plus other easily available data to compute the mass of water vapor in the atmosphere of Venus. Do it in metric and you get an immediate translation into water volume which you can then compare to Earth.

 

[sinwisher]

all other things aside, using a large quantity of nukes on any planet we hope colonize would cause even further problems, such as massive doses of radiation, that last time I heard, were quite dangerous to us frail humans<br />

 

[sernpiat]

I was thinking of Hydrogen Bombs. We have so many of these (H bomb), I thought that if we could use them to help us colonize Venus, it would be pretty neat. Think about it: Weapon of Mass Destruction used to create a world suitable for life...<br /><br />I just being naive. <br /><br />After reading the posts here, I believe that it will be easier to warm up Mars then to cool Venus. <br /><br />

 

[newtonian]

sernpiat- As a compliment to maddad's post, note that Venus also has very little magnetic field -it would be a very dangerous place to live given that lack of protection from the solar wind and charged cosmic rays.<br /><br />However, your thoughts are very important here on earth.<br /><br />There would be ways we could either increase or decrease the temperature of our planet.<br /><br />We are now increasing the temperature, btw.<br /><br />I.e global warming.<br /><br />The subject is of real concern, both now and in the distant future when our sun is thought to go into red giant phase according to the popular standard model of stellar evolution as applied to our sun.<br />BTW- I have some doubts as to popular models.<br />

 

[glutomoto]

Maybe blue green algae can do it.<br /><br />Sure thing, if blue green algae can be taught to fly and the atmosphere not too dry.<br /><br />I think it was a Larry Niven article that made it sound like this could work. I tend to think venus is way to dry for the algae to work.<br /><br /> <div class="Discussion_UserSignature"> </div>

 

[newtonian]

What altitude?<br /><br />Venus' atmosphere changes temperature with elevation, one chart shows 750 degrees Kelvin near the surface, and gradually dropping to about 80 degrees Kelvin 100 km in altitude.<br /><br />This gradual decrease is in contrast with earth, which has a thermosphere which is much hotter- the stratosphere is also heated on earth - due to the ozone shield, I think.<br /><br />What temperatures can blue-green algae endure?<br /><br />Anyway, there are other factors, like sulphuric acid clouds, which make it impossible for algae to survive in the Venutian atmosphere.<br />

 

[newtonian]

maddad - concerning water on Venus.<br /><br />Your post is correct; note also my posted source indicating there is water in Venus' Atmosphere - .005% in a very massive atmosphere contribution to 25% of Venus' greenhouse effect.<br /><br />Also, note that sulfur dioxide is in the atmosphere, and clouds of sulfphuric acid.<br /><br />This chemical formula helps you see the relationship of these compounds:<br /><br />H2O (water) + SO2(sulfur dioxide) yields (=) H2SO4 (sulphuric acid)<br /><br />I know, that is not balanced. The extra oxygen atom can come from photolysis (=photodissociation) of either water or sulfur dioxide.<br /><br />It is likely photolysis is what removed much of the water, the hydrogen would escape into space, and the oxygen would combine with other atoms or compounds.

 

[Maddad]

The thermal profile of the earth's atmosphere is complicated. It decreases steadily with altitude (lapse rate of maybe 6 or 7 degrees per kilometer) until the tropopause at about 15 or so kilometers. It then warms again because of ozone trapping untraviolet light. This lasts until the mesopause at about 50 kilometers where the atmosphere steadily cools again. Finally, at maybe 90 kilometers or so, the atmospheric temperature reverses direction once again because of the interception of high energy cosmic rays. Although the density would make a good laboratory vacuum, the temperature can be as much as 1,000 Degrees Celsius.

 

[glutomoto]

I found...<br /> CYANOPHYTA <br />V. Thermal algae<br /> Blue-green algae of many types survive well at temperatures well over 50C., which is above the temperature most organisms can survive. Blue-green algae are found in hot springs around the world. Some of the algae in Yellowstone live in a normal temperature 85C, while overflow water 90C - boiling point at that altitude. The spectacular colors of the springs at Mammoth Hot Springs, etc., are due mainly to blue-green algae. They also contribute to the mineral depositions so characteristic of the springs.<br /><br /> Carbon Dioxide-Eating Microbe <br />1/10/01 BOZEMAN -- Wanted: Algae of the most adventurous type. Must grow in slime on scratchy plastic discs. A willingness to be periodically purged in favor of new recruits required. Above all, must have a hearty appetite for carbon dioxide and a tolerance for scalding temperatures.<br /><br />IIRC cyanobacteria is credited for making some very large changes to earth way back when, and left some of the oldest fossils. So when you said that changing venus wasn't humanly possible, it seemed right that natures tools might do it.<br /><br />I would also like to suggest that it is humanly possible, aren't we altering planet earth right now? Of course this line of thinking leads me to conclude that we would all have to move to venus. Might be worth doing just to prove brad guth wrong. <img src="/images/icons/laugh.gif" /> <img src="/images/icons/laugh.gif" /><br /><br /> <div class="Discussion_UserSignature"> </div>