More reasons to hate humidity: It expands global warming, prof says

Feb 19, 2009

Here's yet another reason to hate humidity: it expands global warming, says a Texas A&M University professor.

Andrew Dessler, a professor in the Department of Atmospheric Sciences who specializes in research on climate, says that warming due to increases in greenhouse gases will lead to higher humidity in the atmosphere. And because water vapor itself is a greenhouse gas, this will cause additional warming. This process is known as water vapor feedback and is responsible for a significant portion of the warming predicted to occur over the next century.

"It's a vicious cycle - warmer temperatures mean higher humidity, which in turn leads to even more warming," Dessler explains.

The perspective by Dessler and co-author Steven Sherwood of the Climate Change Research Centre at the University of New South Wales is published in the current issue of Science magazine. In the article, they review and summarize the peer-reviewed evidence in support of a strong water vapor feedback and conclude that the evidence supporting it is overwhelming.

"For years, there was a debate over this mechanism, with some even questioning if the water vapor feedback existed at all. But recent work on this feedback has moved its existence and strength beyond argument," Dessler adds.

Predictions of significant global warming over the next 100 years by climate models require a strong water vapor feedback. Recent estimates suggest the earth will warm from 2 to 4 degrees Celsius (4 to 8 degrees Fahrenheit) over the next century - a scenario that could have devastating long-term consequences.

"Everything shows that the climate models are probably getting the water vapor feedback right, which means that unless we reduce emissions, it is going to get much, much warmer on our planet by the end of the century," he adds.

Many scientists believe such warming rates are already happening.

They can point to the summer of 2003, when a prolonged heat wave gripped Europe. According to the Earth Policy Institute, more than 35,000 people died that summer, with France recording over 14,000 deaths and Germany more than 7,000.

Additionally, warmer temperatures are having an adverse effect in the Arctic, where rapid loss of ice is now occurring.

"The only possible way future warming won't be significant is if there exists some sort of off-setting negative feedback, which has yet to be discovered," Dessler notes.

"Most scientists, myself included, judge that to be a pretty unlikely possibility."

Source: Texas A&M University

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OregonWind
4.3 / 5 (8) Feb 19, 2009
Not convinced about this but I would imagine, although this is only speculation of mine, that earth would see more rain and a lot of dry lands could turn into wet lands and probably more plants would flourish and eventually the GW would reverse. Could that also be the case?
MikeB
4.1 / 5 (9) Feb 19, 2009
The biosphere will flourish, the temperatures will moderate. The tropics will cool as the polar regions warm. As the sea levels slightly rise, vast areas that were unproductive will thrive. The deserts will blossom and the earth will become a virtual horn of plenty as mankind fills the new areas and brings a new era of wealth to the world.

Of course that is the optimistic outlook. The truth likely lies between the apocalyptic and the ideal.
Nartoon
4.3 / 5 (6) Feb 19, 2009
Is there some magical reason why Water Vapour would only provide positive feedback to AGW, and no other reasons, like El Ninos etc?
dachpyarvile
1.8 / 5 (5) Feb 20, 2009
Yes! More Hydrogen tech now! :)
mikiwud
3.7 / 5 (9) Feb 20, 2009
More water vapour = more clouds which reflect heat back into space and cause more rainfall which has a cooling effect. This is the NEGATIVE FEEDBACK ignored by the IPCC, big(mouth) AL and Little Jim the nutcase. Anyway, temperatures are falling.
Who but James Hanson could tell the GERMAN Chancelor that coal trains are TRAINS of DEATH and coal powered power stations are FACTORIES of DEATH then call sceptics deniers?
Soylent
2.9 / 5 (10) Feb 20, 2009
Who but James Hanson could tell the GERMAN Chancelor that coal trains are TRAINS of DEATH and coal powered power stations are FACTORIES of DEATH then call sceptics deniers?


He's verifiably correct. ~65k Germans die prematurely by ~14 years from particulate pollution every year. Most of that is coal power.

Every ~14 years you've killed 9 million people. Looks like a holocaust to me.

The reason they don't use nuclear is because technical illiterates think they can have another Chernobyl; but with coal power they're guaranteed one(about 10 each year in fact).
mikiwud
2.7 / 5 (7) Feb 20, 2009
Soylent.
This is the crap I expect from illiterate idiots!
You comletely missed the point.
If you do not know ANY history, don't make a pratt of yourself..shut the f--k up! Obviously Hanson did not realise what he was saying either.
BTW a large percentage of particulates come from diesel engines.
KBK
1 / 5 (5) Feb 20, 2009
I have feeling it is also a deal that takes place between solar activity, speed of change,and a potential capacity for the system to balance itself out. However, if the last be true..change could move so fast that a natural balance attempt by the system -if such a mechanism could realistically be considered to exist- might not be able to 'stem the tide', as it where.

IMHO, Soylent has some valid points. A bit of reason over that of emotion, please. Emotional responses are fine - but with some reason applied to the outburst is de rigueur, I feel.

Diesel fuel fumes are recognized as having within them....the most potent carcinogen known to mankind, as component of the particulate.

This is somehow OK?

WTF?

I have feeling it is also a deal that takes place between solar activity, speed of change,and a potential capacity for the system to balance itself out. However, if the last be true..change could move so fast that a natural balance attempt by the system -if such a mechanism could realistically be considered to exist- might not be able to 'stem the tide', as it where.

IMHO, Soylent has some valid points. A bit of reason over that of emotion, please. Emotional responses are fine - but with some reason applied to the outburst is de rigueur, I feel.

Diesel fuel fumes are recognized as having within them....the most potent carcinogen known to mankind, as component of the particulate.

This is somehow OK?

WTF?

The best way, by far, to IMMEDIATELY clean up coal and diesel fuel usage..is to burn with 'brown's gas'..as an accelerant. The losses of creating the browns gas are totally offset by the efficiency increase, the two are an incredible pair when put together.

Then, the final particulate output remains as 02 and water. That's it. All other particulate is destroyed, consumed by the action of the browns gas. I'd explain exactly why brown's gas is capable of this particular seemingly bizarre trick, but that explanation requires a considerable effort and space. look into it for yourself. it is a real and working science.
mikiwud
4 / 5 (8) Feb 20, 2009
Sorry to harp on about the same subject ,but
Does everyone think it is OK for Hanson to tell the Germans (and everyone else) that coal trains are the same as the Death Trains taking Jews to the Gas Chambers? (Death Factories)
If this the latest Warmist propaganda you are REALLY scaping the bottom of the barrel!
Modernmystic
3.7 / 5 (9) Feb 20, 2009
Sorry to harp on about the same subject ,but
Does everyone think it is OK for Hanson to tell the Germans (and everyone else) that coal trains are the same as the Death Trains taking Jews to the Gas Chambers? (Death Factories)
If this the latest Warmist propaganda you are REALLY scaping the bottom of the barrel!


Yes it's totally ludicrous. What they're forgetting is the BENEFITS that come from the power generated from those coal plants, without which the entire country would revert to pre-industrial life expectancy...talk about a holocaust.

You can't just look at one side of the issue, you have to take the good with the bad.
GrayMouser
4 / 5 (8) Feb 20, 2009
Sorry to harp on about the same subject ,but
Does everyone think it is OK for Hanson to tell the Germans (and everyone else) that coal trains are the same as the Death Trains taking Jews to the Gas Chambers? (Death Factories)...

No, Hansen has gone way over the edge. He's pathological on the subject.
3432682
4 / 5 (8) Feb 20, 2009
Global warming is the current version of the type of environmentalist hysteria which predicted global cooling in the 1970's. They have no clue either way, they just have to keep publishing something because taxpayers worldwide are paying scientists $10 B per year to do pro-warming research.

Anyone who is a skeptic is fired, attacked, villified, and morons like Hanson call for prosecution. It ain't science, folks, it's socialist politics. It infects all of academia and the media.

They want to spend trillions on "solutions" which are not yet feasible, such as solar. They continue to fight nuclear power, the only solution massive enough to do the job. They are selling pessimistic fairy dust.
dachpyarvile
4.3 / 5 (6) Feb 20, 2009
What I find really funny is that the same "scientists" who claim that adding H2O vapor to the atmosphere will increase warming also are the same ones pushing for increased usage of Hydrogen technology, the only by-product of such technology being H2O vapor!

How's _that_ for irony? :)
jonnyboy
3.7 / 5 (6) Feb 20, 2009
It is so rare for me to find a group of individuals intelligent enough to think it through and examine the facts not just the politics. To you a salute, to Soylent a pfffffffft.
dachpyarvile
4 / 5 (4) Feb 21, 2009
Sorry to harp on about the same subject ,but
Does everyone think it is OK for Hanson to tell the Germans (and everyone else) that coal trains are the same as the Death Trains taking Jews to the Gas Chambers? (Death Factories)
If this the latest Warmist propaganda you are REALLY scaping the bottom of the barrel!


Yes, I absolutely agree. I think such statements are overreaching the grasp of reality. And, what in hell's name does soylent's examples of diesel have to do with coal except in that train engines use it? Diesel fuel comes from oil, not coal. Truth be told, there is a lot of hypocrisy in the Gore camp. Read http://www.worldn...ID=54528 to see why.
Duude
5 / 5 (3) Feb 22, 2009
Actually, more people die world-wide from the cold then the heat. So, I suppose global warmers are really pushing population control.
dachpyarvile
5 / 5 (1) Feb 22, 2009
Actually, more people die world-wide from the cold then the heat. So, I suppose global warmers are really pushing population control.


True enough. I seem to recall that 25,000 died during a cold-snap in Europe in the not too distant past. Nowhere near that number died during the extreme heatwaves caused by the blast of hot winds Europe got from the Sahara.

And, most AGW advocates also actually are advocates of population control. A little research will show that to anyone who looks at the data.

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