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Global Warming Mostly Confirmed - On Mars
dinotrac writes "A just-completed 23 month study, carried out over the course of a Martian year, found that the Martian polar ice caps are rapidly eroding, sending large amounts of the greenhouse gas carbon dioxide into the Martian atmosphere. If this pattern continues over time, Mars could go from a planet whose winters are cold enough for dry-ice snow to having a shirt sleeve atmosphere. Humans would still have to provide for oxygen, but plants could go naked.
I wonder if this means tougher emission controls on the next Martian rover?"
This really shouldn't affect local global warming theories. After all, it's only been 23 months, and its the only data we have. We have no real historical record the way we do with earths temperature. (both with ice-cores and with recorded history).
And, earth and mars, obviously, have vastly different atmospheres.
The fact the temperature on mars increased slightly over the past 23 months doesn't actually change anything with regards to mans affect on the earths atmosphere. We already know that earth can change without us, it has in the past.
What we need to find out is how much (if any) effect on our climate we actually cause.
autopr0n is like, down and stuff.
recently overhyped global warming debate ?
I must say I find the accussation that Global Warming is over discussed, hyped, etc... bemusing. To me FOOTBALL is overhyped, CELEBRITY is overhyped, the WEATHER is overhyped- each of these are covered in every news bulletin in the world, every day.
Until people generally have the scientific background to understand these issues there should be more not less discussion in the media. Atmospheric effects of mans activities are poorly understood, so two main points of view are adopted - 'how can little old us effect something so big???' and 'don't piss in the bath'.
The greenhouse effect (the ability for certain atmospheric gases to trap more heat than others - leading to an overall warmer planet) is a scientific fact. Whether the effect is increasing or not is currently being debated - with the vast majority saying yes, it is.
The Mars results are interesting because they demonstrate that even without life, let alone industrial level life, the level of greenhouse gases in the atmosphere can change year on year.
What it does not, cannot, tell us is wether this is a cyclical or progressive change. Thats the same as here on earth. The earth is warmer now than it was 100 years ago.
I'm a 'don't piss in the bath' person myself.
Everyone warned the President what would happen if the US didn't sign on to the Kyoto Protocols.
And it's happening as we speak.
On Mars.
Damn you Bush! Damn you!
Um, yeah, well....
Plants are great, but they don't generate new oxygen, they just recycle the old stuff. If you start with 10^100 moles of CO2 and 10^100 moles of H2O, that works out to, 2*10^100 moles of C, 2*10^100 moles of H and 3*10^100 moles of O (1.5*10^100 moles of O2), right? So, all you need to do is:
a) find a massive source of CO2 (in the gigaton range, to start with) that will give you something close to earth atmospheric pressure
b) find a massive source of water (in the petaton range, to start with) to help with the atmospherics and the temperature stabilization
c) increase a and b to account for losses due to soil mineralization of the O
d) find a lichen that will grow (and reproduce) on Mars
oh yeah,
e) find some way to stimulate some plate tectonics to recycle the minerals and crack the O off the Fe in the crust (this is a long term goal, though)
The man who does not read good books has no advantage over the man who cannot read them. - Mark Twain
Given the "what if we..." comments following up here, I strongly recommend reading Kim Stanley Robinson's "Red Mars", "Green Mars" and "Blue Mars". The books start with a near-future colonization of Mars and go through one very well developed "what if" path, covering not just the technology but also the social and political engineering that follows. The idea of deliberate greenhouse warming shows up, among others.
Oh, yeah: they're also good reading, with an interesting set of characters.
Which impact will this discovery have on the recently overhyped global warming debate ?
It will give ammunition to people who, having an interest in not cutting back in CO2 emissions, want to argue that the global warming we've observed recently on earth is a "natural" phenomenon.
Firstly, this isn't an observation of increased temperature on mars. This is an observation of polar CO2 erosion. No temperature increase (which has been observed on earth) has been observed on Mars.
Secondly, we allready knew that climate change occurs periodically and naturally. The fact that Mars may be in the process of exiting a "dry ice age" at the moment indicates nothing about the earth.
Furthermore, I'm going to take common-sense issue with the scientists announcement that this (which they have observed over only 1 yr. martian) is "definitely not a seasonal trend." They can't know that. As an example, the ice sheets could melt in summers and reform every third or fourth winter which hapened to be extra cold. Point is there would be no long term change. I don't see any data on the actual rate at which these ice sheets are eroding, either.
The Earth, on the other hand, is allready warm by recent-meteorological standards (personally, I'm a great fan of the theory that the himalayas caused the ice ages by stripping CO2 out of the atmosphere - Nova did an episode about it.) The rate at which CO2 is going back into the earth's atmosphere is highly unusual given our knowledge of the climatic history of the earth so I don't see how our much-more-limited knowledge of the climate on Mars reveals much.
Speaking of flame wars, I have to resist the impulse to insult the previous poster. This has nothing to do with the ozone layer!
The good and new comes from no quarter where it is looked for, and is always something different from what is expected.
At such low pressure, some of the water in the soft tissues will vaporize and cause swelling of the human body (note that the blood will not vaporize, because it is always under sufficient pressure in the blood vessels). This can be prevented by "a properly fitted elastic garment", but such garments are only know to work at pressures of more than 20 millibars.
Which means that a lot of carbon dioxide would be needed until you could walk around without a space suit.
Just 23 months is pretty much nothing in terms of planetary cyclical events. Maybe this warming is just part of a very long cycle in Martian atmosphere, taking decades of even centuries, that we haven't observed yet. I'd hate to see the November 13, 2614 headlines of The Martian Times stating something like "Global cooling confirmed - atmosphere compromised".
(BTW, will Greenpeace stablish a Martian Chapter called "Redpeace"?)
"Trust me - I know what I'm doing."
- Sledge Hammer
Expect blue skies on Mars in less than an hour!
<joke>
"Pinky, you've left the lens cap of your mind on again." - P&TB
"I can see my house from here!" - ST:
This graph from this report shows a striking correlation between the length of solar cycles and mean temperature over the last hundred years (interesting that the length of the cycle should give the best correlation - the authors suggest the shorter solar cycles correspond to higher solar output).
Also, there is considerable historical evidence that the current change in climate is really pretty small beer compared to what has happened in the past:
"The Norwegian farmer Folke Vilgerdson made the first attempt to settle in Iceland in about 865 AD... He lost his cattle in a severe winter and disappointed went back to Norway after having seen a fjord filled up by sea ice. Therefore he called the country Iceland. Only a few years later, in 874, Ingolf Arnason succeeded. He was followed by many others, and settlement was completed in 930 AD... In 982, Erik the Red discovered new land West of Iceland. He called it Greenland; according to the Greenlander Saga this was only to persuade people to follow him... But the O(18) curve suggests that the name described a reality... So the drastic climatic change [warming] late in the ninth century may be part of the reason why Iceland and Greenland did not get the opposite names." (Dansgaard: Palaeo-Climatic Studies on Ice Cores, in Oeschger, Messerli and Svilar, 1980).
Here is another account, also suggesting that Greenland had a suprisingly comfortable climate at the time.
It can't hurt to cut down on CO2 emission, even if it's not the 100% cause of global warming.
Yes it can. It can remove cheap energy and transportation sources for billions of people, maintaining or increasing rates of poverty and starvation around the globe.
But if it turns out that it was the influence of man, there won't be an 'undo' button!
Yes, there will. The "undo" button will be to reduce CO2 emissions after we've proven that they are a problem, and watch them fall back to equilibrium. We haven't passed some invisible "point of no return"; the Earth isn't currently the hottest it's been this millenium, much less the hottest ever.
This means that the oxygen, nitrogen and carbon are probably in the soil. This would explain why Mars is so red (all that oxidized iron) and why the atmosphere is so rarefied (most of the gases are tied up as permafrost, adsorbed gas or chemical compounds like nitrates). It also means that the right kind of change can release them and make them into a thick atmosphere again.
Bob Zubrin of the Mars Society has written that we could start what would probably be a substantial greenhouse effect on Mars with only a few million tons of greenhouse gases (such as sulfur hexafluoride and methane) per year. This is the output of one large-scale industrial plant. Once you start heating the soil the adsorbed gases come out and the permafrost melts, leading to more warming and more gas release. Once you've got 200 millibars of atmosphere you can walk around outside with nothing fancier than a heavy parka and an oxygen mask. That's not bad for a planet that's currently an iceball with 7 millibars of fire-extinguisher contents for "air".
Scientists restrict study to entire physical universe; creationist
I'm shocked that a NASA scientist would make such sweeping statements and predictions based on what the article portrays as a few photographs over on year of Mars history.
They don't seem to rule out that this ice is being shifted to another location. Perhaps the other pole? Could it be settling underground in solid form? Yes, they make some comments about ravines and such, but the comments are superficial.
As I think I saw another poster mention, could it be a part of some longer event cycle? Could some other chemistry be at work, with the CO combining with something else instead of transforming to a gas?
There are lots of questions that weren't answered about the WHY and WHERE. Not to mention that this throws more evididence at the global warming issue of Earth. If Mars is warming, perhaps the Earth warming is a part of some larger issue such as a warmer period in a solar cycle. Perhaps we are moving through a warmer part of the galaxy/universe and that's making everything hotter. Perhaps the higher gaseous CO2 levels on earth are due do higher temperatures on the planet, and not the other way around.
Article X: The powers not delegated... by the Constitution...are reserved...to the people
the Earth isn't currently the hottest it's been this millenium, much less the hottest ever.
Hate to disagree, but it is the year 2001, making this millenium currently in its first year. Therefore, the temperatures being recorded now for this year are by definition the hottest of the millenium (and coldest too).
Lawrence Lessig is my personal hero.
>Yes it can. It can remove cheap energy and transportation sources for billions of people, maintaining or increasing rates of poverty and starvation around the globe.
I am always amazed at the short-sightedness of ppl. These ppl are already starving and inputing more energy will NOT imporve the situatation. Energy will NEVER be cheap again except for short durations. It will be in russia's interest to raise the price again and they will do so. OTH,had we passed Kyoto, then ppl (ecpecially USA) would have started working on increasing our efficiencient useage of energy as well as a conversion to something else. Segway is certainly interesting as would be the Highspeedmonorail.com. Personally, I think that as a society, that we are very short sighted. Oil has better uses than as energy. Think about all the plastics and pharmaceuticals that we use.
>Yes, there will. The "undo" button will be to reduce CO2 emissions after...
This is also an unknown. Somebody mentioned useing iron in the oceans. This may have the side affect of introducing red-bloom killing all life. Any number of actions that we take may actually introduce a number of side-effects that cuase more problems than they solve. Saying that we can do something on a QUICK global scale is truley the unknown and the ultimate in hubris.
Back on Topic, is Mars undergoing global warming? almost certainly it is. Just as earth is. The difference is that earth is suppose to be heading for ice age, if billions of years can be beleived. Mars will almost certainly head back as well unless we step in and perhaps cuase more sublimation of co2. Once we get there (most certainly not with the idiot that is in office) and look over the planet, I hope that we use some mirrors over the poles to keep the process going.
Yay! Another uninformed know-it-all!
There is no scientific debate about whether or not global warming (on earth) is occuring. We have global average temperatures for a 150 years. This data shows a clear warming trend over the last 12 years or so. No amount of wishful ignorance can make these numbers go away.
The debate is whether or not we are causing it. However, the ignorant often group them, which parallels the debate around evolution. People say that they don't "believe" evolution happens, when scientists have observed it happening. The scientific debate is over natural selection, and to what extent it is the main mechanism for evolution.
As long as people perpetuate inane talking-heads style opinion over scientific fact, our populus will remain ignorant. Which is to say, will always be the case.
Working toward a usable PDA environment in the spirit of Newton OS: Dynapad
Here are some "cool" animations where you can see the ice caps melting. Also, here's a JPL press release which is a little more level headed than the news coverage.
There are 10 types of people in this world, those who can count in binary and those who can't.
I always thought that the gravity on Mars was low enought that the atmosphere just leaked away.
The escape velocity at the surface of Mars is only a little less than 1/2 of what it is at the surface of the earth. The thermal velocity of a particle scales with the square root of temperature. Hence a gas particle on Mars would only have to be a fourth as hot as it's Earth bound cousin in order to escape.
Now the particle has to not only be hot, but also have enough room to move that it can get away into space without hitting other gases and cooling off. This isn't really a problem since light molecules naturally drift to the higher levels, and in the case of Mars, it's pretty rarified air to begin with. Atmospheres (in the inner planets) drop off dramatically in the scale of hundreds or thousands of kilometers, whereas the planet is several 100,000s of kilometers in radius, so being high in the atmosphere only cuts a few percent off of escape velocity.
Now the real problem here is when you look at the numbers. On Earth, H2 and He won't escape at room temperature. In fact, they have to be heated to between 10 and 100 times room temperature (Kelvin Scale) in order to escape. We assume that cosmic rays, solar wind, and other atmospheric phenomena can give this much energy to an appreciable percentage of H2 and He so that non-neglible amounts bleed away into space. In any case it's not a very fast process at current.
N2 and O2, being 7 and 8 times the mass of He would have to be heated to 7 and 8 times as hot as He to escape. Given the historic composition of the atmosphere on Earth we can assume that this degree of heating is rare enough to have a pretty neglible impact on atmospheric composition.
However, if you have a considerable incidence of unshielded ionizing radiation then single atoms of N and O might be present in significant quanities and would need only 3.5 and 4 times the temperature of He's escape.
As I said, in the beggining, on Mars you can escape while being only 1/4 the escape temperature on Earth. So, yes, it is possible that ionizing radiation produces enough atomic N and O that an appreciable portion of it can escape into space. Temperatures may even be high enough to bleed of non-trivial quantities of N2 and O2 from Mars, but remember it's still a rare event since the temperatures needed are well about the surface temperature and little of the air will ever get hot enough. Could this alone account for the thin martian atmosphere? Probably not. More likely the dominant phenonema involves gases being absorbed into rocks and mineral deposits.
On one final note, thermal differentiation of atmospheric composition was probably most important early in the life of the solar system when the sun was significantly hotter. What is around today isn't likely to change much by virtue of bleeding gases into space.
This should be glaringly obvious, but the author clearly didn't want the facts to get in the way of a good story.
1) This happens every year anyway. The martian atmosphere gets thicker every year as a result of its less-than-circular orbit. Every year, there are times when Mars is closer to the sun than the rest of the year, which allows the planet to absorb more solar energy, melting more of the carbon dioxide in the ice caps and adding to the atmosphere. This might actually snowball if it weren't for the fact that there are other times of the year where the CO2 starts to freeze out, snowballing in the other direction.
2) While it might be exciting and all that in a million years, you *might* not need a spacesuit to walk on the surface of mars, more than likely it's just a statistical anomaly because it was slightly warmer this year than last. As if we never see that sort of thing on earth or anything. The author saves this little tidbit of information for last, because otherwise there's not much of a story here at all. (and of course, there really isn't.)
3) This is, if anything, simply proof that some years the sun is hotter than others, which might be a much easier explanation for an increase in the average surface temperature of the earth in recent years over the theory that the media likes to push that we're all to blame. The media likes this theory simply because scaring people is good for business. As in this article, it's not the actual facts that matter as much as an exciting story.
"No problem. I have the capacity to do infinite work so long as you don't mind that my quality approaches zero."-Dilbert