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Water Vapor Causing Climate Warming
karvind writes "According to BBC, new studies suggest that water vapor rather than carbon dioxide in the atmosphere is the main reason why Europe's climate is warming. The scientists say that rising temperatures caused by greenhouse gases are increasing humidity, which in turn amplifies the temperature rise. This is potentially a positive feedback mechanism which could increase the impact of greenhouse gases such as CO2. Even though 2005 will probably be warmest year, climatologists still differ in opinion"
Assuming this your post wasn't completely tongue-in-cheek...
So, in order to "mine" the water vapor out of the atmosphere, you would need some way of condensing the vapor. Any sort of heat exchanger would work, but the laws of thermodynamics dictate that, in the end, you would just be heating the atmosphere up more than accomplishing anything else. This does assume that the control volume for the system is the earth itself, and you're not using space as your 'cold reservoir'--doing that gets into all sort of pesky heat transfer issues as space is rather non conductive. There is something to be said for radiation, but it would only really be effective if shielded from the sun. Anyway, since the most likely mediums for heat rejection would probably be either the atmosphere (you lose), the ocean (you lose again), or the terrestrial bits of the earth (you lose still), all you would be doing it heating the atmosphere up more and putting more water vapor into the atmosphere in the long run.
If your toast does not accquire any kind of royalty, please do not contact us. We can't help you.
It's that kind of black and white approach to this and other topics, both by the people and especially the media, that has trivialized the issue at hand.
it's always useful to apply Fisher's deduction:
"The more issues a person attempts to shoehorn down into an artificial liberal/conservative dichotomy, the more certain you can be that the person is an American."
Debate about climate change is a debate in the US because the whole issue is deconstructed and soundbitten into a pair of simplistic politicised extremes with nary a scrap serious reasoning left. If you actually read the IPCC reports, and the peer reviewed criticisms (as opposed to the op-ed pieces) there's a lot less debate than you might think, and neither position is anywhere as extreme as the soundbites and op-eds make out. The climate is warming, we have some decent ideas as to what factors are causing it (and they are many and diverse), and it seems human actions are somewhat of a factor. Don't take my word for it though, actually do some reading on your own.
Jedidiah.
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I wouldn't dispute that, since about 1800 it has. But there is a problem, which I've never seen adequately addressed, with the IPCC Hockey Stick curves. This the controversy with Mann et al. We do know from historical evidence that there actually was a Medieval Warm period, and the evidence is that it was hotter than now. There was also a cool period in around 1700. Both of these vanish from the record with the IPCC hockey stick curves. Then, if you get into how these curves were derived, lets say just that the derivation is very remote from any observational evidence.
So two things trouble one. First, the rewriting of history without apparent reason. Second, the lack of any explanation of what caused the Medieval Warm period. Not human activity, that's for sure - or at least, not the industrial revolution. And what caused the decline after it?
But there is a problem, which I've never seen adequately addressed, with the IPCC Hockey Stick curves. This the controversy with Mann et al. We do know from historical evidence that there actually was a Medieval Warm period, and the evidence is that it was hotter than now. There was also a cool period in around 1700. Both of these vanish from the record with the IPCC hockey stick curves. Then, if you get into how these curves were derived, lets say just that the derivation is very remote from any observational evidence.
That's a fairly strong claim. I think you'll find that Mann recognises medieval warm periods and cooler periods in the 1700s. The medieval warm period just isn't warmer than present temperatures in his reconstruction based on proxy data. In fact, that's the case for most reconstructions based on proxy data from a wide variety of sources. There are differences in the different reconstructions, but in general there's a reasonable amount of agreement. Don't take my word for it though, here's a plot with 10 different reconstructions along with full citations of the source papers for each so you can check the methodology on each of them. Given the variety of methods used for derivation amongst those reports, from glacier records to tree rings, it's at least resonably convincing.
As to alternative views - the only evidence I've seen for a significantly warmer medieval period is derived from exactly the same data as Mann's, in roughly the same manner, so if you think one is suspect... What we do have is one report by two Canadians, one an economist the other a businessman, claiming radically different results from everyone else using different slightly techniques. I'm not writing them off, but I would be interested to see a little more work on the issue, especially when there are discussions of issues with their techniques (and nice simplified versions) that seem quite reasonable.
None of this is to say that McIntyre and McKitrick are wrong, but one has to ask why you believe them and dismiss the ten other reports by different people that generally agree quite well.
Jedidiah.
Craft Beer Programming T-shirts
If you check my posts you will see that I have been saying this for years.
Most of this is probably due to a lot of land at high elevation. This causes a cooling because water vapour falls out at high elevation and cannot trap the incomming solar radiation. Furthermore we get a high reflection off the snow and ice as well.
In all likelihood the cooling from the Miocene was caused by mountain building with the himalyan plateau being the latest addition. The Rockys and Andies, Pyrannies, Alps and 2 Hellenic ranges appeared before the Himalain plateau was pushed up. In North America we have the Colorado Plateau.
As part of this cooling Antarctica froze over and that locked the planet into the current snowball earth. Prior to this freeze over Antactrica was cold - but still had significant amounts of water vapour which trapped solar energy falling during the Antarctic summers. After the freeze over, Antarctica became the dryest continent on the planet - with a huge increase in the loss of solar energy falling on Antarctica. So this is a powerful positive feedback mechanizm that locked us into the current snowball earth phase.
Since then a lot of erosion has taken place which my have moved us past the equilibrium point. Still - the ice on antarctica and the glaciers at high elevation have kept us locked into the snowball earth phase.
I suspect that irrigation is causing a warming. It makes a great deal of sense. But offsetting this is the distruction of the rain forests.
CO2 is negligable. During the ordovician levels of CO2 were 13x to 19x higher than now and the earth cooled.
Some have pointed out correctly that the sun was not as strong back then. While that is true - there was a fair amount of mountain building during the ordovician (taconic orogany) and this may have been what tipped the planet from the hot house into the snowball phase. The sun was also weaker when the planet came out of the snowball phase a few million years later.
For over 80% of the last 540 million years the earth has been about 22 degrees warmer on average than now. So it makes sense that the earth will warm up - we just do not know when.
Another thing is that we have had about 22 ice cycles in the last 2+ million years and typically with a frequency of about every 100,000 years or so. 5 million years ago there were trees north of the Arctic circle in Canada. This is probably true of Russia as well.
Since we have had a number of ice cycles (the last was at peak about 50,000 years ago) it would make sense that we will have another. If so then we may be within a few 1000 years of another ice age developing.
It really will depend on where the equilibrium points are and I don't think anyone has any real idea.
One thing that is really instructive is to look at a globe of the earth that has actual mountains on it. There is one at the Tyrrell Museum in Drumheller Alberta. When you look at this globe and see just how thin the atmosphere really is - 2/3 of it lies below 30,000 feet for instance (Mount Everest) - it becomes very clear that a lot of solar incident energy is simply reflected off into space.
Get rid of the mountains and you gain a very effective H2O blanket.
In the tropics at sea level and 35C the absolute H2O vapour in the atmosphere is over 8% (80,000 ppm). This is in contrast to CO2 levels of 365 PPM.
H2O is a stronger absorber than CO2 by far - in all wavelengths.
So I frankly do not think CO2 is even a factor to be honest. The models used by the IPCC do not take into consideration that water vapour levels may be changing. When your most significant variable is not handled properly then your model isn't very believable.
From a paleoclimate standpoint - CO2 can change climate. It did several times in the Precambrian. The thing is that in order to do this the CO2 levels had to climb to many 1000 PPM. This occurred back then because so much of the earth froze over that even the oceans may have frozen r