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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Had a 125ft driveway, in a tiered mountainous (relatively speaking) N NJ neighborhood.

House on one side. Wall up to the next house on the other. 20 ft slope up on front of driveway.

Imagine shoveling that.

As perspective, neighbor to the S was 20ft lower and neighbor to the N 25ft higher.
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I botched that didn't I? 70F. :)
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Deleted for blog speed.
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Quoting Seastep:


Don't miss it one bit.

Can't wait (was going to do it this year, but didn't work out) to send my daughter up to my sister up in Syracuse.

She keeps saying she likes it, but when we were in NJ, 5 minutes max and back in the house.

I think she is remembering the hot chocolate.


I truely do not miss it either, I grew up in West Hempstead, LI in the late 70's when we had 37" of snow fall within 2 weeks. I had to shovel that crap. I am in mild North TX, where it can be 70F in Dec, Jan and Feb!
Member Since: August 25, 2009 Posts: 20 Comments: 6785
TC Olga is no more, she is now a rain maker.

Member Since: September 30, 2007 Posts: 9 Comments: 15935
Quoting Bordonaro:
Nashville, TN, my daughters house at 4pm today. She lives 1 mi from the Nashville Int'l AP. She said so far they have about 4" and it's still snowing, I just finished giving her a hard time on Facebook!



Don't miss it one bit.

Can't wait (was going to do it this year, but didn't work out) to send my daughter up to my sister up in Syracuse.

She keeps saying she likes it, but when we were in NJ, 5 minutes max and back in the house.

I think she is remembering the hot chocolate.
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Quoting PcolaDan:


Isn't it fun to pick on the kids!!!! LOL

My daughter just told me there is a snowman at the door knocking!

Yes it is! I have 5 total. My eldest step-sons are 37 and 34. My 3 natural children are going to be 27, 26 and 23 in 2010. I have 10 grandchildren. And I am only 48!
Member Since: August 25, 2009 Posts: 20 Comments: 6785
Quoting Bordonaro:
Nashville, TN, my daughters house at 4pm today. She lives 1 mi from the Nashville Int'l AP. She said so far they have about 4" and it's still snowing, I just finished giving her a hard time on Facebook!



Isn't it fun to pick on the kids!!!! LOL
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A guy in a Prius passed me doing 60mph in a
40mph zone this morning. Had a Audobon Society
sticker on the back, must be what they call hyper mileage.
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Nashville, TN, my daughters house at 4pm today. She lives 1 mi from the Nashville Int'l AP. She said so far they have about 4" and it's still snowing, I just finished giving her a hard time on Facebook!

Member Since: August 25, 2009 Posts: 20 Comments: 6785
Quoting Chicklit:

yeah, no kiddin'
pot is illegal...while they approve drugs that mess up your capacity to think 24-7 and aren't even sure how they work (ie. seratonins et al.)
we all know that the world is not fair.
anyway, off to read about FDR's rise from elite opulence to populist prez.
ah...here's the moon.
mars the tiny dot to its left.


The Beehive cluster is also between the Moon and Mars tonight, so try to look for it if you have a telescope. The moon rises at sunset and sets at sunrise tonight.

In Canada, the Prime Minister is trying to pass a bill (C-15) without debate in the House of Commons. This is contrary to how the bill system works. All this while parliament is shut down, mostly due to the PM avoiding the Afghan detainee issue.
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Quoting transitzone:


Study of combined harm to community and individuals of various drugs, done by British scientists advising the government in 2006, results ignored becuase they weren't what the g'vmnt expected or wanted to see. I don't find the actual report at the moment, but here's the ranked results. Stay thirsty, my friends


LOL Interesting stuff. Actually didn't expect a response to this. The knowledge base here on Wunderground is deep. I like that.
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As mentioned, climate science is in its infancy. Why you get "coming ice age" and "coming global warming."

Which is fine, in perspective of a relatively new science. It works out over time as it evolves as more is learned.
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Nasa was once a remarkable organization.
Lost a bit of luster over the years.
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NASA Directed Toward Climate Change, But Not the Moon
Posted 2010-01-29
There will be money lacking for NASA's Constellation program, the program designated to return humans to the moon by 2020.

The White House will instead direct NASA funding to concentrate on Earth-science projects -- principally, researching and monitoring climate change, -- and on a new technology research and development program that will make human exploration of asteroids and the inner solar system possible.
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...WINTER STORM WARNING FOR ALL OF CENTRAL NC...

EVENING UPDATE:
STRONG LOW-MID LEVEL THETA-E SPREADING EAST INTO THE AREA IN ADVANCE
OF THE MATURE MID-LEVEL CYCLONE NEAR THE ARKLATEX...IN TANDEM WITH
SHEARED MID-LEVEL VORT ENERGY RESULTED IN A SW TO NE BAND OF
LIGHT TO MODERATE SNOW EXTENDING EAST TO WEST ACROSS THE WESTERN AND
CENTRAL PIEDMONT THIS EVENING BETWEEN 5 TO 8 PM. INTERESTING ENOUGH
THIS SNOW BAND IS IMPACTING THE MAJOR POPULATION CENTERS OF CENTRAL
NC...WITH AS MUCH AS 1.5 TO 2.0 INCHES OF SNOW ALREADY BEING
REPORTED IN BOTH THE TRIAD AND TRIANGLE
(SEE RDUPNSRAH FOR FULL LIST
OF SNOWFALL REPORTS). WHILE THERE WILL BE SOME BRIEF LULLS IN THE
MODERATE SNOWFALL...THIS EXPANSIVE/ELONGATED BAND EXTENDS ALL THE
WAY BACK ACROSS UPSTATE SC. SO MANY OF THE SAME AREAS COULD SEE
ANOTHER 1 TO 2 INCHES POSSIBLE THROUGH MIDNIGHT
...BEFORE THE
STRONGER ISENTROPIC LIFT SPREADS OVER THE AREA AFTER MIDNIGHT. AS
SUCH...WITH A 2 TO 3 INCH BASE LAYER OF SNOW IN PLACE BEFORE THE
ARRIVAL OF THE BEST FORCING...MAY HAVE TO RAISE SNOWFALL AMOUNTS IN
THE SWEET SPOT WHERE THIS BAND HAS FORMED
. BUT THAT WILL BE
ADDRESSED AT A LATER UPDATE AS WE CONTINUE TO MONITOR TRENDS.

Yes, I am in the snow sweet spot tonight! Anyone else?
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Quoting JFLORIDA:
Water vapor of course. By far.

All I ask is dont initiate a discussion unless it is going to be on a sourced technical level. There are some articles appearing in the popular press lately pointing out concentrations that have been known and discussed for 50 years. I hope this isn't what that inquiry is about.


Source is sat temps. Source is blog entry.

Bottom line is, it is a very uncertain, at best, theory, as it pertains to CO2.
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170: Yes, El Nino is weakening, but only because it's spreading out. I compared the SST maps from WeatherUnderground for December 29 and for today, and I found that in the month, all of northwestern Humboldt isotherms retreated south and east (except for a few of the equatorial ones, but the Humboldt doesn't even reach the equator anymore without dodging part of the ENSO warm pool), while all of the isotherms at the southwestern part of the current, the part that threatens to cut the Humboldt off, have advanced southeastward, in some cases dramatically, for example with the 23C line. An area of 26C+ water now stretches from the equator to coastal South America, down to central Peru and strengthening the warm anomaly in the Peru-Chile region that threatens to undermine the current from the northeast. Nearly all warm currents and anomalies in the Southern Hemisphere have expanded while cold currents retreated, although collision areas such as that off the coast of Northern Argentina in the South Atlantic has had small fingers of warm water colliding with each other continuously after previous collisions have spun into themselves. The warm pool in the Southwestern Atlantic has encroached into the bay that separates Argentina and Uruguay. In the Northern Hemisphere, most warm currents have retreated, especially the Gulf Stream from the coast of Norway while the diversion in the current, the one east of Newfoundland to west of Greenland, has strengthened. I'll also note that the Gulf Stream was broken on December 29, before diverting west of Greenland completely but temporarily on January 5. (I was going to write up a blog on this today, but ran out of time) El Nino should be mostly gone around July, and should reach a neutral phase around September.
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Quoting PcolaDan:


So is half blown okay?


JUST KIDDING!!!!!!!!!

Actually I'm surprised it's not just controlled as a prescription drug. I really don't see it anything different as so many that, over time can be addictive and cause damage if used improperly. Admittedly, I don't know the pharmaceutical pros and cons of this though.


Study of combined harm to community and individuals of various drugs, done by British scientists advising the government in 2006, results ignored becuase they weren't what the g'vmnt expected or wanted to see. I don't find the actual report at the moment, but here's the ranked results. Stay thirsty, my friends
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Quoting KEEPEROFTHEGATE:


Shouldn't she also be ordering a jumbo everything but make the soda diet? :)
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Member Since: July 15, 2006 Posts: 171 Comments: 53866
Quoting SevereHurricane:


God... that has to feel miserable. The coldest temperature I have ever been in is 19F.


Yup, we get temperatures like this every winter (except for the really warm ones such as 2006-06). But this is the coldest temperature for the winter so far, and this winter has been fairly mild and snow-free, save for the intermittent squalls, the one major snowstorm, and the cold snaps. While the Southern US has been complaining about cold and extreme weather, farther north we've seen barely any of that, at least in terms of departure from normal, except for the North American storms.
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Quoting KEEPEROFTHEGATE:
or taking some time off in the timeout room

science has abandoned them, they don't have the
run of the roost any more.
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Quoting Seastep:


What is the #1 greenhouse gas?


He invited discussion, not a pop quiz from the good Dr. Seastep.
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"It does look slow in here tonight... what happened to all of the crazies that have been on lately?"

you must have them on ignore.......
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Quoting Bordonaro:


Well, I guess they're outside howling at the Full Moon..
or taking some time off in the timeout room
Member Since: July 15, 2006 Posts: 171 Comments: 53866
Everyone complaining about cold? This is cold!



Photos from Gambell, Alaska. A Yupik Village on St. Lawrence Island out in the Bering Sea. The tip of the Island is located about 40 miles or so from Siberia.

Strange. It was -52C, but we felt really cold. We couldn’t stay outside more than 15 minutes. But when we registered -57.1C in Tomtor on the day of our depature for Yakutsk, it was bearable. We were even surprised at such a low temp at that moment.
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Evening all,

Finally some snow in Raleigh, NC (pics on my blog), woohoo! So far, I calculated we are getting it at a rate of 0.6 inches per hour.
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Quoting Orcasystems:
It does look slow in here tonight... what happened to all of the crazies that have been on lately?

Pretty bad when KOG & PCD and the bad boys


Well, I guess they're outside howling at the Full Moon..
Member Since: August 25, 2009 Posts: 20 Comments: 6785
It does look slow in here tonight... what happened to all of the crazies that have been on lately?

Pretty bad when KOG & PCD are the bad boys
Member Since: October 1, 2007 Posts: 81 Comments: 26511
And just 2 days ago, it was 68F and NOW:
Dallas / Fort Worth International Airport
Lat: 32.91 Lon: -97.03 Elev: 560
Last Update on Jan 29, 8:53 pm CST


Light Snow

31 °F
(-1 °C) Humidity: 79 %
Wind Speed: NW 17 G 25 MPH
Barometer: 30.08" (1018.8 mb)
Dewpoint: 25 °F (-4 °C)
Wind Chill: 20 °F (-7 °C)
Visibility: 7.00 mi.


Member Since: August 25, 2009 Posts: 20 Comments: 6785
Quoting JFLORIDA:
I wonder, these findings in no way dispute the premise of AGW.

Greenhouse gasses in the atmosphere warm by adsorbing/readmitting in spicifc, understood wavelengths.

Man has disrupted sinks and altered the balance of these gasses in the atmosphere.

At no point has any of this been disputed. They are factors in the physical world.

The degrees of complex interactions are what is being discussed now.

If you dont want to discus atmospheric science, observe respect for others that do.


What is the #1 greenhouse gas?
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You're bad KOTG. LOL.
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215. Poor smiley face is banging its head against the brick wall, and the other is just beating that freaking dead horse!
Member Since: August 25, 2009 Posts: 20 Comments: 6785
Space program anyone?

Seriously, I am very disappointed in the recent news.

If they continue the shuttle program, ok, but to have no means of delivery other than delivering satellites?

Unless I am misunderstanding, that is the case, no?
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Quoting Orcasystems:


I am just innocently watching.. as per normal.. watching KOG dig :)


Got this ready for you ---

And in case you need it ---
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More sleet/snow to come....


New Bern, North Carolina (Airport)
Updated: 22 min 51 sec ago
Overcast
34 °F
Overcast
Windchill: 25 °F
Humidity: 56%
Dew Point: 20 °F
Wind: 13 mph from the ENE
Pressure: 30.28 in (Falling)
Visibility: 10.0 miles
UV: 0 out of 16
Clouds:
Overcast 6000 ft
(Above Ground Level)
Elevation: 16 ft
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innocent when your sleeping
Member Since: July 15, 2006 Posts: 171 Comments: 53866
Quoting PcolaDan:


So is half blown okay?


JUST KIDDING!!!!!!!!!

Actually I'm surprised it's not just controlled as a prescription drug. I really don't see it anything different as so many that, over time can be addictive and cause damage if used improperly. Admittedly, I don't know the pharmaceutical pros and cons of this though.


I must confess, as a teenager I did "unwise things". Marijuana is not a physically addictive drug, like opiates, nicotine, alcohol, etc. However, "walking around in a continual blitzed out of your mind state" is not good for your brains cells, kills your ability to focus and concentrate, affects your short and medium-term memory, reduces testosterone levels and is not good for your lungs for that matter.
Member Since: August 25, 2009 Posts: 20 Comments: 6785
I was wondering where P451 got such zoomed in output of the models. GFS and...NAM?
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Quoting Orcasystems:


I am just innocently watching.. as per normal.. watching KOG dig :)
lets get one thing straight its call stirring
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Quoting CybrTeddy:
Global warming is a bit of an err... rough subject for lack of a better word. Best not to get involved in any type of arguments Keeper.


No arguments. I'm a discussion guy. :)

Anyway, really would like to get your take on the Ares news.
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Quoting Bordonaro:

Orca is lurking quietly, as KOG tries to throw Orca, the killer whale, under the bus! I love political cartoons, however, some of them go just a "wee bit" too far.


I am just innocently watching.. as per normal.. watching KOG dig :)
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Member Since: July 15, 2006 Posts: 171 Comments: 53866
202 - Never said that, did I? :)

Quite the opposite.
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Quoting CybrTeddy:
Global warming is a bit of an err... rough subject for lack of a better word. Best not to get involved in any type of arguments Keeper.


iam not getting involved just posting some funny pictures
Member Since: July 15, 2006 Posts: 171 Comments: 53866
Patrap

Yeah,,science is hard for some to get..especially past their own Bias to the er,subject matter.

Im gonna walk da dog,..and come back later to see the er,.."discussion".

LOL


That is like the pot calling the kettle black.
Warmies need to check there bias when the Cold
reality waps them in the face.

I do recall some claiming a warming trend in Feb. I wonder who?

http://www.dw-world.de/dw/article/0,,5168198,00.html

Will February see a return of the big freeze?
Paul Hudson | 17:23 UK time, Thursday, 28 January 2010

A lot of you have sent me e-mails asking me the same question: Will we see a return to the cold and snowy conditions that affected us a few weeks ago?

Over the next 24 hours an Arctic northerly will develop, as predicted by the various worldwide weather models in my update on Sunday, with a cold weekend in prospect.

Longer term as you might expect forecasting is a much more difficult job to get right, but there are signs of what might lie in store.

We have already discussed stratospheric warming in previous blogs. The idea is that extra warmth in the stratosphere can cause a blocking type of weather to develop in the troposphere, the area of the atmosphere where weather patterns affect us. Well, stratospheric warming commenced last week. This suggests that a blocking pattern of weather is possible into February.

Other indicators we look at are pressure patterns across the Arctic and the North Atlantic. Both the North Atlantic oscillation (NAO) and the Arctic oscillation (AO) have gone into their negative phase again, having temporarily turned positive around the middle of the month - and are forecast to stay that way into early February.

Without getting too technical, both these pressure pattern changes suggest that the jet stream could be pushed to the south of us once more, leaving us susceptible to colder air, with high pressure likely to build to the north of us - dragging cold air across us from the east.

None of these 3 features are a guarantee of a prolonged cold spell of weather - but the balance of probabilities are now tilting towards this being the most likely scenario.
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Quoting Bordonaro:


Chicklit, I am not saying its ok to be a full blown pot-head,


So is half blown okay?


JUST KIDDING!!!!!!!!!

Actually I'm surprised it's not just controlled as a prescription drug. I really don't see it anything different as so many that, over time can be addictive and cause damage if used improperly. Admittedly, I don't know the pharmaceutical pros and cons of this 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.