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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?"
..tougher emission controls on the next Martian rover..
They have dogs there? So, emission controls like 'Don't crap of the Martian face' are needed?
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We must stop polluting the martian atmosphere! It's all man's fault! Damn those fossil fuels!
Oh wait, it's not man's fault.
Hmm. I wonder if we would pause to look at man's contribution to our own "global warming." Maybe we aren't as significant as we think.
I demand a million helicopters and a DOLLAR!
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.
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
True.
But one idea put forth about Global Warming on Earth is that there is an effect from solar flares. The CO2 posse has flatly rejected that, because of course you can't bitch about the sun.
Perhaps the warming on Mars's polar caps is evidence of an effect from the solar flares.
Or perhaps it's evidence that climates will undergo changes without American SUVs.
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.
The Ozone layer and global warming are NOT related. So many people see these as the same thing, and they are not. The hole in the ozone layer simply allows for more UVB to reach the ground. The UVB has been linked to skin cancer, cataracts, damage to materials like plastics, and harm to certain crops and marine organisms and that is it. The green house effect is where a blanket of gases is formed around the earth that traps radiation and is natural and we need it. It stabalizes our temperature. But too much of this effect is what is believed to cause global warming.
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.
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'.
Hear, here! Meterologists don't have the slightest idea of what is going on is our atmosphere these days. IANAM, but I am a mathematician who does some fluids, so I'm hearing from these atmosphere guys all of the time. No serious scientist claims to understand these mechanisms.
What we do know is that the tempature of the planet has risen, pretty dramatically, over the last century, and the amount of CO2 in the atmosphere has risen steadily over the last 300 years. This is not necessarily a causal relationship, but we do have a mechanism by which they would be related (i.e. more CO2 -> more greenhouse effect -> more temperatures). Of course, we don't know that we are causing any of it. For example, maybe the sun got brighter, or whatever, and so the earth heated up, and this caused many plants to die, leading to an increase in CO2. There is (speculative) evidence that we are causing it, however, to some degree.
I think you're right about the two major points. The first position people take is specious. There are many examples of humans causing drastic biological and environmental changes. We have certainly caused changes big enough to end up affecting us. Can we raise the temperature of the earth? Who knows. We can, however, release enough junk into the air to wreck our own worlds, we have proved this time and again. I guess I'm more in the "don't piss in the bath" camp, because once we mess it up, it may very well be permanent. It is worth our while to be cautious.
Another thing which the anti-global-warming politicians and pundits need to be worried about: if the earth is warming up independent of us, this is not a victory for them! For example, let's say that we have some very small affect on global warming, and most of the warming is some natural process. We will then need to curb our emissions even more, because then we have less room for error. For example, if you're on a fixed income, and inflation goes up, you have to spend less. It's not your fault inflation went up, but you have to spend less anyway. Not fair, but c'est la vie.
Come on, give it up, that's
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
All of these posts about sending up a machine to generate/liberate the CO2 and we can live on Mars in 20 years.
If it is that easy, why don't we just build a big plant here on earth to suck up all of the greenhouse gases and CFC's? Surely it must be easy to counteract the effects of the worlds ENTIRE industrial production. Then I can go buy an SUV and blast the A/C without any guilt.
It all sounds very simple in theory. Do you realize the volume of gas that you would have to generate? How about the amount of energy that you would have to produce to power the devices? Even the staunchest proponents of global warming say that it will take hundreds of years for the cumulative effects of our ENTIRE industrial system to spoil the Earth's atmosphere. What makes everyone thing that a couple of little plants that we put on Mars could do anything?
Peter Jennings: "Tax cuts proposed by President Bush could jeopardize funding for a NASA/EPA mission to restore ice caps on Mars."
Dan Rather: "Most scientists we talked to agreed the ice caps melted after the Mars rover landed. Have we created an SUV problem on Mars?"
Oprah: "On today's show we have Jane A. Token, NASA's Director of Space Ecology, to give us the women's perspective on the future of space exploration."
Tom Daschle: "We need the Republicans to stop blocking funding for our new program to hire Mars ice watchers as federal employees to raise the level of professionalism..."
I wrote parts of this stuff
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
Deploy a massive solar powered heating elements which raised the ambient temperature near the CO^2 glaciers. This might have the effect of accelerating the rate of melt, or sustaining a rate of melt if the change is seasonal.
I don't know what kind of heating system you'd want... the idea of monsterous hair dryers with heating elements blowing "hot air" over the martian glaciers is an amagingly funny image to conjure, but you could also bore pipes through the glacier and run hot liquid through the pipes... and I'm sure someone with a better science background than mine could come up with more.
Honestly though, this is something that's been talked about for years. Sci-fi authors have speculated about any number of ways in which we could terra-form mars. And many of them are scientifically sound. The problem is this:
Going to mars costs money. Terra-forming mars will cost alot of money. No individual, no matter how long lived, will ever see a teraforming project through from beginning to end... and few people are willing to start such a massively expensive endeavor when there is no payoff in thier own lifetime (nor the lifetimes of the next three or four generations).
Without doubt, this announcement is good news. It gives more for Sci-fi authors (self included) to work with to write plausable fiction. Remember, the best of sci-fi authors have a good grasp of physics / biology / astronomy when writing. That's why Aasimov and Sagan and the other Grand Masters have been able to write their imortal works... because they understand science well enough, that years later we aren't laughing and saying "wow, shows how little they knew!"
Okay, I'm done with my mini rant... back to work.
If I can't see it in Lynx I'm not interested.
The earth is warmer now than it was 100 years ago.
And significantly cooler than it was 900 years ago which was warmer than 100 years before that. etc. etc. ad nauseum.
What it does not, cannot, tell us is wether this is a cyclical or progressive change.
You are right - observing such a change on Mars tells us very little about whether the current global warming on earth is part of a cyclical or progressive change. Fortunately we have much more data on temperatures on earth and KNOW that there are cyclical changes and that over the most recent centuries the cycle has gone from temperatures significantly higher than today (the medieval warm) to temperatures significantly cooler than today (the little ice age).
I would agree it is worthwile studying the most recent upswing in temperatures because it is possible that human activity *could* be contributing to the most recent cycle of global warming. It seems though looking at the cycle of global climate change over the past millenium that our contribution is insignificant if it is present at all. We are neither at historically high temperatures nor experiencing changes that are particularly rapid.
I'm a 'don't piss in the bath' person myself.
Funny, that is how I think of those that would 'piss in the bath' of the global economy, wetting themselves in fear over what all the data suggests is a natural and cyclical change.
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.
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