Stratospheric water vapor decline credited with slowing global warming

By: Dr. Jeff Masters , 6:18 PM GMT on January 29, 2010

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After a steep rise in global average temperatures in the 1990s, the 2000s have seen relatively flat temperatures, despite increasing levels of CO2 emissions by humans. This reduced warming may be partially due to a sharp decrease in stratospheric water vapor that began after 2000, according to research published yesterday in Science by a team of researchers led by Dr. Susan Solomon of NOAA's Earth System Research Laboratory in Boulder. Water vapor is a potent greenhouse gas capable of significantly warming the planet, and its potency is much higher when it is located in the lower stratosphere where temperatures are extremely cold. Greenhouse gases located in cold regions of the atmosphere are more effective at heating the planet because they absorb heat radiation from the Earth's relatively warm surface, but then re-emit energy at a much colder temperature, resulting in less heat energy lost to space. Even though stratospheric water vapor can exist at concentrations more than 100 times lower than at the surface, the 10% drop in stratospheric water vapor since 2000 noted by Solomon et al. acted to slow down global warming by 25% between 2000 - 2009, compared to that which would have occurred due only to carbon dioxide and other greenhouse gases.


Figure 1. Stratospheric water vapor in the tropics, between 5°S - 5°N, as measured by the HALOE instrument on the Upper Atmosphere Research Satellite (UARS), between 1993 - 2005. The bottom portion of the plot shows the lower stratosphere, just above where tall thunderstorms are able to transport water vapor into the stratosphere. A strong yearly cycle is evident in the water vapor, due to the seasonal variation in heavy thunderstorms over the tropics. Once in the lower stratosphere, the waver vapor takes about 1.2 years to travel to the upper stratosphere, as seen in the bending of the contours to the right with height. Note that beginning in 2001, very low water vapor concentrations less than 2.2 parts per million by volume (ppmv) began appearing in the lower stratosphere, due to substantial cooling. Image credit: Rosenlof, K. H., and G. C. Reid (2008), Trends in the temperature and water vapor content of the tropical lower stratosphere: Sea surface connection, J. Geophys. Res., 113, D06107, doi:10.1029/2007JD009109.

The observations
We haven't been able to observe water vapor in the stratosphere very long--accurate global measurements only go back to 1991, when the HALOE instrument aboard the Upper Atmosphere Research Satellite (UARS) began taking data (Figure 1). Stratospheric water vapor showed an increase of about 0.5 parts per million by volume (ppmv) during the 1990s. But after 2000, a sudden drop of 0.4 ppmv was observed, and this decrease has persisted into 2009. To see how these changes impacted the amount of global warming, Solomon et al. fed the observations into a specialized high-resolution model that computed the change in heat from the fluctuating water vapor levels. They found that the increase in stratospheric water vapor in the 1990s led to about a 30% increase in the amount of global warming observed during that decade, and the decrease of 0.4 ppmv since 2000 led to a 25% reduction between 2000 - 2009.

How water vapor gets into the stratosphere
The stratosphere has two main sources of water vapor: transport from the lower atmosphere (the troposphere) via tall thunderstorms, and the chemical breakdown of methane gas into water vapor and carbon dioxide. With regard to greenhouse effect warming, transport of water vapor by thunderstorms is the most important source, since this mechanism delivers water vapor to the lowest part of the stratosphere, where temperatures are coldest and greenhouse gases are more effective at warming the climate. There is a limit as to how much water vapor that can enter the stratosphere via thunderstorms, though. Temperature decreases with altitude from the surface to the bottom of the stratosphere, where they begin to rise with height due to the solar energy-absorbing effect of the stratospheric ozone layer. As moisture-laden air rises in thunderstorms towards the lower stratosphere, it encounters the atmosphere's "cold point"--the coldest point in the lower atmosphere, at the base of the stratosphere. Since the amount of water vapor that can be present in the atmosphere decreases as the temperature gets colder, and moisture being transported to the stratosphere must traverse through the "cold point" of the atmosphere, the air gets "freeze dried" and loses most of its moisture.


Figure 2. The departure from average of tropopause temperature (dark line) and Sea Surface Temperature (light dashed line) for the tropical Pacific Ocean between 10°S - 10°N, from 1981 - 2007. The tropopause is the bottom boundary of the stratosphere. The SST data is for 139°W - 171°W longitude, and is from the NOAA Optimal Interpolation v2 data set. The tropopause data is from balloon soundings, for the region 171°W - 200°W. The SST is plotted so that the anomalies increase as one looks down. Note that prior to about 2000, tropopause temperatures and SSTs increased and decreased together, but that beginning in 2000 - 2001, a sharp climate shift occurred, and the two quantities became anti-correlated. The sudden drop in tropopause temperature in 2000 - 2001 caused a sharp drop in stratospheric water vapor. Image credit: Rosenlof, K. H., and G. C. Reid (2008), Trends in the temperature and water vapor content of the tropical lower stratosphere: Sea surface connection, J. Geophys. Res., 113, D06107, doi:10.1029/2007JD009109.

Why did stratospheric water vapor drop in 2000?
Tall thunderstorms capable of delivering water vapor into the stratosphere occur primarily in the tropics, particularly over the Western Pacific, where a huge warm pool with very high Sea Surface Temperatures (SSTs) exists. In 2000, this region experienced a sharp increase in SST of 0.25°C, which has remained consistent though the 2000s (Figure 2). Coincident with this increase in SST came a sharp drop in the "cold point" temperature of the tropopause--the lower boundary of the stratosphere. This reduction in "cold point" temperature meant that less water vapor could make it into the stratosphere over the Tropical Pacific, since more thunderstorm water was getting "freeze dried" out. Did global warming trigger this increase in Pacific SST, resulting in cooling of the "cold point" and less water vapor in the stratosphere? Or was it random variation due to some decades-long natural cycle? This key question was left unanswered by the Solomon et al. study, and observations of stratospheric water vapor don't go back far enough to offer a reasonable guess. One factor arguing against global warming having triggered a negative feedback of this nature is that prior to 2000, increases in Western Pacific SST caused increases in "cold point" temperatures--behavior opposite of what has been seen since 2000.

If global warming has triggered the decrease in stratospheric water vapor seen since 2000, it could mean that the climate models have predicted too much global warming, since they don't predict that such a negative feedback exists. On the other hand, if this is a natural cycle, we can expect the recent flattening in global temperatures to average out in the long run, with a return to steeper increases in temperature in the coming decades. Climate models currently do a poor job modeling the complex dynamics of water vapor in the stratosphere, and are not much help figuring out what's going on. Complicating the issue is the fact that about 15% of all thunderstorms capable of delivering water vapor into the stratosphere are generated by tropical cyclones (Rosenlof and Reid, 2008), and tropical cyclones are not well-treated by climate models. We also have to factor in the impact of stratospheric ozone loss, which acts to cool the lower stratosphere. This effect should gradually decrease in future decades as CFC levels decline, though. The stratosphere is a devilishly complicated place that can have a significant impact on global climate change, and we are many years from understanding what is going on there.

References
Romps, D.M., and Z. Kuang, "Overshooting convection in tropical cyclones", Geophysical Research Letters, 2009; 36 (9): L09804 DOI: 10.1029/2009GL037396

Rosenlof, K. H., and G. C. Reid (2008), Trends in the temperature and water vapor content of the tropical lower stratosphere: Sea surface connection, J. Geophys. Res., 113, D06107, doi:10.1029/2007JD009109.

Portlight Haiti update
Paul Timmons, who directs the Portlight.org disaster-relief charity that has sprung up from the hard work and dedication of many members of the wunderground.com community, was interviewed by NBC yesterday. The reporter doing the story is planning to follow the Portlight-donated goods to Haiti and interview the people with disabilities that receive the donations. It is uncertain when the story will be aired, but I'll try to give everyone a heads-up.

Next post
My next post will probably be Tuesday (Groundhog's Day), when I plan to discuss Phil's forecast for the rest of winter. I'll throw in my two cents worth, too.

Jeff Masters

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Quoting Tazmanian:
dont you guys find it odd with snow falling inn DC right now in DC the temper for them is 18 and they are geting snow dont you guys think it odd for them to be geting snow at a temper of 18??? i find it kind of rare and not some in you see or find all the time


It's the humidity -- it's always the humidity when you live on swampland, lol. That's our standard answer for anything; not much surprises us.

Seriously, it is a bit weird, Taz. DOES it have anything to do with the humidity, which is currently at 89 percent?

Member Since: August 19, 2008 Posts: 32 Comments: 1918
Quoting P451:


Nope. Not the cobra either. It was a name given to specialty models. It was still a 5.0 but it was heavily modified. It did 60 in first gear.

On the tip of my tongue but I just can't think of it.

Shame the kid killed himself in it.



Steeda, Rouch, P51
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dont you guys find it odd with snow falling inn DC right now in DC the temper for them is 18 and they are geting snow dont you guys think it odd for them to be geting snow at a temper of 18??? i find it kind of rare and not some in you see or find all the time
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We don't need no stinkin' winter tires! (Seriously, correct about "winter" tires, even all-weather radials didn't cut it on my Mustang.)



Photo by Don Olson, "Deer Herd in Playground," Friends of Sligo Creek website.
Member Since: August 19, 2008 Posts: 32 Comments: 1918
that one thing i dont like about winter storms for the E coast they are vary hard too forcast and some time the mode runs can be way way off has you can see with this storm there haveing now
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Quoting Tazmanian:
hey whay gives 1st they said the E Coast snow storm wont make it up too new york and i this look at the rader for new york and it looks like the snow is not too far off from there

i think they got the track for this storm way way off and talk about a mass up forcast for DC they where 1st saying that snow will not get too them but now they are geting like 1 too 2" per hr snow fall rats the track for this storm was way way off if any one have not noted it yet


yeah, it definitely went farther north than expected. Evansville Indiana (southern Indiana) was only supposed to get 1-3 inches, and they got 6-8
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hey whay gives 1st they said the E Coast snow storm wont make it up too new york and i this look at the rader for new york and it looks like the snow is not too far off from there

i think they got the track for this storm way way off and talk about a mass up forcast for DC they where 1st saying that snow will not get too them but now they are geting like 1 too 2" per hr snow fall rats the track for this storm was way way off if any one have not noted it yet
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Quoting AstroHurricane001:


Wow, that's ridiculous. Thanks for that.




You need winter tires.


no problem!
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Quoting tornadodude:


I have a tool on firefox that tells me where each website is from, and thus us what they gave me: link


Wow, that's ridiculous. Thanks for that.


Quoting AwakeInMaryland:
Guess you know it's SNOWING in the DelMarVa!



[Pic. from Friends of Sligo Creek website]

[I had a little red 1992 Mustang ragtop for quite awhile -- it was dangerous on wet roads, never mind in snow. It was fun, but all our cars will be at least front-wheel drive from now on.]


You need winter tires.
Member Since: August 30, 2008 Posts: 8 Comments: 2835
here is the truck I had:





then I sold it (Gas guzzler) and bought a '92 Honda Accord :p
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Guess you know it's SNOWING in the DelMarVa!



[Pic. from Friends of Sligo Creek website]

[I had a little red 1992 Mustang ragtop for quite awhile -- it was dangerous on wet roads, never mind in snow. It was fun, but all our cars will be at least front-wheel drive from now on.]
Member Since: August 19, 2008 Posts: 32 Comments: 1918
Quoting AstroHurricane001:


Explain? A few days ago I've heard people criticizing the CBC for censoring the rallies by Canadians Against Proroguing Parliament across the country, and giving in to the influences of the ruling Conservative party.


I have a tool on firefox that tells me where each website is from, and thus us what they gave me: link
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Ok, so this funny link
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Quoting tornadodude:
Lol this "Canadian" website is based in the US,

http://www.cbc.ca/canada/story/2010/01/28/ufo-newfoundland-pmo.html


Explain? A few days ago I've heard people criticizing the CBC for censoring the rallies by Canadians Against Proroguing Parliament across the country, and giving in to the influences of the ruling Conservative party.
Member Since: August 30, 2008 Posts: 8 Comments: 2835
Lol this "Canadian" website is based in the US,

http://www.cbc.ca/canada/story/2010/01/28/ufo-newfoundland-pmo.html
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Quoting Ossqss:
157, just curious. Considering all that is now happening with respect to the IPCC report, you are comfortable with non-scientific opinion from advocacy groups (ie. WWF on many) making global policy decisions for you? \\

Have a look, this only addresses one of the coming issues with the IPCC> There are many more coming out of the woodwork. I just don't like dishonesty, period. \

IPCC's Himalayan Glacier 'Mistake' No Accident

You do realize my comment has nothing to do with who is making decisions for me? I was just pointing out the fact that cal extrapolated a point from the doc's post that wasn't even really there. Nothing about the doc's post seemed biased towards either side of the argument. If anything, I'd say the information was suggesting a greater sense of caution in our decision-making, i.e. gather more data.

Frankly, I'm still pretty much of an agnostic on this issue. I don't see that the alleged falsification of data IN AND OF ITSELF means that the globe is not warming. I don't see sufficient evidence IN AND OF ITSELF that any warming taking place is man-made. I see there is a lot of information out there, some of it contradictory, some of it not well understood even by the scientists who are studying the data. I see the validity of erring on the side of caution, especially if it means we get beneficial side effects, such as a cleaner earth and better building standards, more inexpensive renewable energy sources, etc.

Your point, at least to me, is .... well.... irrelevant.
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This comparison (Jan. 27 vs Jan. 29) won't be available in these images for long, but here they are below, for SSTs. According to the Jan. 29 image, by that time the <8C zone on the Gulf Stream had already retreated to completely the Western Hemisphere.



Member Since: August 30, 2008 Posts: 8 Comments: 2835
Quoting Orcasystems:


Don't scare me like that... you made me run to the window saying WTF .... its to warm to be snowing



That's a problem for the Olympics, especially with so much rain in BC.
Member Since: August 30, 2008 Posts: 8 Comments: 2835
Quoting buckstop40:
So in one billion years, how much of the surface will have rotated through the core to be recycled? Supposing the sun does not run out of fuel before then.


Do you mean the earth's core running out of fuel or the Sun? Or are you talking about the surface of the Sun, or the plates of the Earth? If you do not get an answer here, you might want to try the Wikipedia Reference Desk.
Member Since: August 30, 2008 Posts: 8 Comments: 2835
So in one billion years, how much of the surface will have rotated through the core to be recycled? Supposing the sun does not run out of fuel before then.
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Rain, rain and more rain. 45 minutes from here, a lot of snow.
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Oh I just looked again, it was night then I guess I saw rain drifting sideways in the light assumed it was snow. Nice view in the light of day.
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Wunderground SST map for today:



The 8C+ zone of the Gulf Stream off Norway has almost completely retreated from the Western Hemisphere. Just yesterday, in fact only a bit more than 12 hours ago, there was still some water at that temperature clinging to the coast of central Norway. Now, it's almost gone. Just three days ago, there was actually some 10C water in that area, and now it's below 8C. I noticed that there is a storm in that region drifting southwest around another low pressure system over central Europe, and that must be having an effect on the current. East of Newfoundland, the Gulf Stream diversion continues to strengthen, and at that latitude the water is as warm as 16C. Nowhere else in the world at that northern latitude (aside from an area near Sakhalin) is that warm in the oceans, especially not in the Atlantic. This means that the diversion is strengthening, and that large storms will periodically continue to strengthen it.

The Humboldt Current has also retreated significantly from yesterday. Yesterday, the northernmost extent of the 20C line extended almost to the Peru-Chile border, reaching close to the 21C line on the northeastern side, close to the warm anomaly at the Peru-Chile coast. Today, it is retreating toward the 19C line. Just three days ago, a portion of the <19C water pointed northeast, toward the ENSO warm pool before being blocked and diverted equatorward. Currently it is pointed completely toward the coast, in a direction in which it can now only retreat.

Tropical Cyclone Nisha has almost dissipated, but its remnants are drifting toward 30C water, where it could potentially encounter low wind shear again (which is what tore it apart), and redevelop. However, the strong tropical cyclone scenario heading toward South America now appears unlikely. Although wind shear is currently strong and increasing ahead of the storm, which is moving into drier air, its remnants are protected by an anticyclone. A separate system is developing northeast of Fiji. The storm's winds have also pulled the ENSO warm pool eastward in the past few days.
Member Since: August 30, 2008 Posts: 8 Comments: 2835
It looked like snow was that just rain.
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Quoting gordydunnot:
Orca nice blog enjoyed watching snow fall on critter cam.


Don't scare me like that... you made me run to the window saying WTF .... its to warm to be snowing

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That still looks like one helluva shower wsw of Tampa in the gulf. Hope it dissipates before it gets to land. I imagine if it was serious Tampaspin would be on top of the situation.
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Quoting KEEPEROFTHEGATE:
no they will slow down to 90

lol

;) btw. a tempo limit in germany would help reduce emission. Something the us and most of the world has not to regulate - at last.
Member Since: September 22, 2005 Posts: 11 Comments: 2032
Quoting gordydunnot:
I guess that wont be doing a hundred plus on the autobahn today.
no they will slow down to 90

lol
Member Since: July 15, 2006 Posts: 169 Comments: 53296
I guess that wont be doing a hundred plus on the autobahn today.
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Quoting Orcasystems:
Your UFO is a French SLBM :)
yep unconfirm french missle test from sub near the french saint pierre islands off newfoundland
Member Since: July 15, 2006 Posts: 169 Comments: 53296
Orca nice blog enjoyed watching snow fall on critter cam.
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Your UFO is a French SLBM :)
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Sno Storm in germany with reported winds of up to 100 km/h and 24 cm snow. The worst storm system (effect wise) till winter begun here.




Member Since: September 22, 2005 Posts: 11 Comments: 2032
Taking time to respond to a few of the comments from last night...

282: That's not a UFO. That's the high cirrus tops of the anvil of the cumulonimbus cloud showing irridescence. Nacreous clouds in the stratosphere often take this effect as well.

Now, here is a real UFO in Canada, and one that coincided with the arrival of the Prime Minister back into Canada.

BTW, 191 is not propaganda. If that's propaganda, then so are 99% of political cartoons.
Member Since: August 30, 2008 Posts: 8 Comments: 2835
Quoting 954FtLCane:
BTW.. to the person who told me Iguanas weren't going to die after the cold snap in S Fla... read your facts.... we had tons of them die... I lost a bunch of plants also and a little skeletal surprise.... stench wise..... and we had the same at work... Iguanas died everywhere down here,,, oh well
i said they would be ok if it was cold one or two nights and as long as it warmed up to above 40 during the day then there may have been a higher survial rate but come on it was sub freezing for a week with day time highs barely reaching 40 you may not of made it if trap outside yourself
Member Since: July 15, 2006 Posts: 169 Comments: 53296
Yes Keeper you were the one that told me Iguanas wouldn't die.... can you fes up now that the stench is in the air and you were wrong...... fes up brother.....
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Quoting gordydunnot:
Looks like some rough weather cranking up in the mid gulf. Could get interesting in Central Fl. later today. There is a buoy out there with a wave height anomaly.But dont know how to interrupt it, looks like .3 meter sudden rise. Also buoy's right around it are showing counter clockwise rotation wind directions at speeds in the upper 20's. BP in the 29.79 area not to low.
here is latest still visible
Member Since: July 15, 2006 Posts: 169 Comments: 53296
Quoting P451:


Cold dry air in NJ and PA is just crippling it's northward movement.

I'm up for snow apparently but I don't see how it's possible.

\
well nj elected a republican... so no more snow ever.....
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BTW.. to the person who told me Iguanas weren't going to die after the cold snap in S Fla... read your facts.... we had tons of them die... I lost a bunch of plants also and a little skeletal surprise.... stench wise..... and we had the same at work... Iguanas died everywhere down here,,, oh well
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MAF provide positive ET hardware overview for early SD HLV test flight
“Orion Team: A few news bureaus and bloggers have been reporting on some major changes coming our way. Sometimes the number of reports gives the impression of validity when in fact they are all reporting on the same rumor,” noted Orion Project manager Mark Geyer, via one of several memos acquired by L2.

“I can tell you that I have not received any direction or information that would confirm what they are saying. That being said, it wouldn’t surprise me to find out that there will be some changes announced next week and that they may be significant.

http://www.nasaspaceflight.com/2010/01/maf-provide-positive-et-hardware-overview-for-early-sd-hlv-t est-flight/
Member Since: September 22, 2005 Posts: 11 Comments: 2032
Quoting gordydunnot:
Looks like some rough weather cranking up in the mid gulf. Could get interesting in Central Fl. later today. There is a buoy out there with a wave height anomaly.But dont know how to interrupt it, looks like .3 meter sudden rise. Also buoy's right around it are showing counter clockwise rotation wind directions at speeds in the upper 20's. BP in the 29.79 area not to low.

Micro-analyzing a shower... it sounds like
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Looks like some rough weather cranking up in the mid gulf. Could get interesting in Central Fl. later today. There is a buoy out there with a wave height anomaly.But dont know how to interrupt it, looks like .3 meter sudden rise. Also buoy's right around it are showing counter clockwise rotation wind directions at speeds in the upper 20's. BP in the 29.79 area not to low.
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Quoting P451:


Good god. I would have definitely murdered myself if I had a mustang. A friend of mine did. There was a specific model name for it. I can't recall it to save my life. It wasn't the Saleen it was something else. He tracked it at 184mph. The car was sick.

Anyone who lives around MD knows what this is. Fort McHenry tunnel. This was around 3am if I recall. I was doing over 100 easy. Can't get away with that these days. Cameras.




An interesting bit about these cars their digital speedometers only went to 85 in MPH and then they pegged. It was the law Ford told me. They did have an E/M switch though. That pegged at 199 kph (125mph). I'm surprised I never took a photo of the 199. I guess I was being safety conscience. lol. This was actually my first car, a cougar as well. 86 as well. Just a V6 but that thing had pep too.



The eventual happened, but, it actually wasn't my fault. A 72 LTD ran a stop sign. Yeah, I had no shot against that thing.





Yeah, that hurt. That's from 55 mph to a dead stop. Had a good cut along my shoulder to my chest from the seat belt. Cracked my shin against the bottom of the dash board assembly. Smacked my face on the steering wheel - despite wearing a seat belt. It just didn't quite catch in time. Still saved my ass though.


And that, is about as much as you bloggers will get into my life. My past life. Almost 20 years gone now. Can't believe it.


Shelby?
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AOI

AOI

AOI

AOI

Humor in Comments
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little cool this morning as the storm to the south drags down the cold air
Member Since: July 15, 2006 Posts: 169 Comments: 53296
Interesting read, but I think that stratospheric water vapor is just too small to have an effect. Even on days where the atmosphere has very high thin cirrus clouds, the ground is able to radiate normally. And this would be a lot more than 2-3 ppm from high cirrus. So I am skeptical that a small drop in stratospheric water vapor (2-3 ppm) would have any effect at all on surface temperatures. Interesting though.
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.