The climate is changing: the Arctic Dipole emerges

By: Dr. Jeff Masters , 3:53 PM GMT en Diciembre 11, 2009

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The dramatic loss of Arctic sea ice in recent years has created a fundamental new change in the atmospheric circulation in the Northern Hemisphere that has sped up sea ice loss and is affecting fall and winter weather across most of the Northern Hemisphere, according to several recent studies. Arctic sea ice loss peaks in September and October, exposing a large area of open water that heats the air above it. This extra heat has helped drive September - November air temperatures in the Arctic to 1°C (1.8°F) or more above average over about half of the depth of the lower atmosphere (Figure 1). This deep layer of warm air has grown less dense and expanded, pushing the top of the troposphere (the lower atmosphere) higher. The result has been a decrease in the pressure gradient (the difference in pressure) between the North Pole and mid-latitudes. With not as much difference in pressure to try and equalize, the jet stream has slowed down in the Arctic, creating a major change in the atmospheric circulation for the Northern Hemisphere.


Figure 1. Cross section of Arctic temperature anomaly from 1000 mb (the surface) to 300 mb (roughly, the height of the top of the lower atmosphere or troposphere). Cross section is taken along the Date Line (180°W), from 60°N latitude (left side) to the North Pole (right side), for September - November for the 12-year period 1998 - 2009. Three year averages were done to reduce the amount of year-to-year noise associated with natural variation. Other cross sections along different lines of longitude show similar results, though typically with more warming aloft and less warming at the surface. Image credit: NOAA/ESRL.

A new atmospheric pattern emerges: the Arctic Dipole
In a 2008 article titled, Recent radical shifts of atmospheric circulations and rapid changes in Arctic climate system Zhang et al. show that the extreme loss of Arctic sea ice since 2001 has been accompanied by a radical shift of the Arctic atmospheric circulation patterns, into a new mode they call the Arctic Rapid change Pattern. The new atmospheric circulation pattern has also been recognized by other researchers, who refer to it as the Arctic Dipole (Richter-Menge et al., 2009). The old atmospheric patterns that controlled Arctic weather--the North Atlantic Oscillation (NAO) and Arctic Oscillation (AO), which featured air flow that tended to circle the pole, now alternate with the new Arctic Dipole pattern. The Arctic Dipole pattern features anomalous high pressure on the North American side of the Arctic, and low pressure on the Eurasian side. This results in winds blowing more from south to north, increasing transport of heat into the central Arctic Ocean. The Arctic Dipole pattern occurred in all summer months of 2007 and helped support the record 2007 summer reduction in sea ice extent (Overland et al., 2008). Overland et al., 2010 also found that the Arctic Dipole pattern tended to create an increase in easterly winds in the lower half of the atmosphere of 40% in fall, between 2002 - 2008. Fall 2008 through spring 2009 featured the old AO pattern. The new Arctic Dipole pattern re-appeared in June - July 2009, but the old AO pattern dominated in August - September, resulting in greater sea ice extent than in 2007 and 2008. The Arctic Dipole pattern was active again in October, inactive in November, and reasserted itself this December. As a result, Arctic sea ice reached a new record minimum for a 10-day period in early November, increased above record lows during late November and early December, and appears poised again to reach a new record minimum later this December (Figure 2).


Figure 2. Sea ice extent in the Arctic for this year (blue line) compared to the record low year of 2007 (green line) and 1979 - 2000 average (gray line). One could make the ice loss looks less significant by using the full satellite data record from 1979 - 2008 for the average. Image credit: National Snow and Ice Data Center.

Arctic Dipole blamed for colder winters in East Asia
It turns out that the new Arctic circulation patterns help to intensify the Siberian High, a large semi-permanent region of surface high pressure prevalent in winter over Siberia. According to Honda et al. (2009), this results in increased flow of cold air out of the Arctic in early winter over eastern Russia, Japan, Korea, and eastern China, causing colder temperatures. By late winter, the pattern shifts, resulting in colder than average temperatures from East Asia to Europe.

Arctic Dipole blamed for drier winters in Northern Europe
Francis et al. (2009) found that during 1979 - 2006, years that had unusually low summertime Arctic sea had a 10 - 20% reduction in the temperature difference between the Equator and North Pole. This resulted in a weaker jet stream with slower winds that lasted a full six months, through fall and winter. The weaker jet caused a weaker Aleutian Low and Icelandic Low during the winter, resulting in a more negative North Atlantic Oscillation--a pattern that usually brings reduced winter precipitation over Alaska and Northern Europe and increased precipitation over Southern Europe. A more negative NAO also tends to bring cold winters to eastern North America and Europe. Though it was not mentioned in the article, reduced Arctic sea ice may also cause dry early winter conditions in the U.S. and the Caribbean (Figure 3). The authors noted that strong La Niña or El Niño events can have a much larger influence on the wintertime atmospheric circulation, which will overshadow the changes due to Arctic sea ice loss.


Figure 3. Difference in early winter precipitation (November - January) between five years that had low Arctic sea ice (2005, 2006, 2007, 2008, and 2009), and five years that had unusually high Arctic sea ice extent (1981, 1984, 1986, 1989, 1993). Note that low sea ice may be responsible for dry conditions in early winter for the Caribbean and most of the U.S.

Commentary
Arctic sea ice loss appears to have created a new atmospheric circulation pattern that brings more warm air in the Arctic, creating a positive feedback loop that causes even more sea ice loss. This feedback loop increases the likelihood that an ice-free Arctic in the summer will indeed come by 2030, as many Arctic experts are predicting. It's worth noting that such an atmospheric circulation shift was not predicted by the climate models. Indeed, the loss of Arctic sea ice over the past three years exceeds what any of our models were predicting (Figure 4). While we can rightly criticize these models for their inaccuracy, we should realize that they are just as capable of making errors not in our favor as they are of making errors in our favor.


Figure 4. Arctic sea ice extent from observations (thick orange line) and 13 model forecasts used to formulate the 2007 IPCC report (light lines). The thick black line is the multi-model ensemble mean, with the standard deviation plotted as a dashed black line. Image has been updated to include the observed 2008 and 2009 measurements. None of the models predicted the record 2007 sea ice loss. Image credit: Arctic sea ice decline: Faster than forecast by Stroeve et al., 2007.

References
Francis, J.A., W. Chan, D.J. Leathers, J.R. Miller, and D.E. Veron, 2009, "Winter Northern Hemisphere weather patterns remember summer Arctic sea-ice extent", Geophysical Research Letters, 36, L07503, doi:10.1029/2009GL037274.

Honda, M., J. Inoue, and S. Yamane, 2009. Influence of low Arctic sea - ice minima on anomalously cold Eurasian winters, Geophys. Res. Lett., 36, L08707, doi:10.1029/2008GL037079.

Overland, J. E., M. Wang, and S. Salo, 2008: The recent Arctic warm period, Tellus, 60A, 589.597.

Overland, J. E., and M. Wang, 2010: Large-scale atmospheric circulation changes associated with the recent loss of Arctic sea ice. Tellus, 62A, 1–9.

Richter-Menge, J., and J.E. Overland, Eds., 2009: Arctic Report Card 2009, http://www.arctic.noaa.gov/reportcard.

Simmonds, I., and K. Keay (2009), Extraordinary September Arctic sea ice reductions and their relationships with storm behavior over 1979.2008, Geophys. Res. Lett., 36, L19715, doi:10.1029/2009GL039810.

Wu, B., J. Wang, and J. E. Walsh, 2006: Dipole anomaly in the winter Arctic atmosphere and its association with sea ice motion. J. Climate, 19, 210-225.

Zhang, X., A. Sorteberg, J. Zhang, R. Gerdes, and J. C. Comiso (2008), Recent radical shifts of atmospheric circulations and rapid changes in Arctic climate system, Geophys. Res. Lett., 35, L22701, doi:10.1029/2008GL035607.

Jeff Masters

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Quoting Patrap:
Later JF,,my cue to split just arrived.

And it aint here..LOL


The rain is crazy 11 inches so far this month here, 4.36 today
Member Since: Mayo 25, 2008 Posts: 0 Comments: 250
so any1 of u believe the panhandle of FL will get some snow .. i know its about 2 weeks away.. but it seems the models have been doing good that i believe..
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Quoting atmoaggie:
18 Z GFS backs off on the snow for the N Gulf coast a bit, but brings in the cold for the 21st, 22nd. For the FL peninsula, 0 C line south of Tampa ?!? with some light precip north of there...



GFS has been real insistent that someone along the gulf coast is going to get some snow, though, this is lightest bit of snow it has come up with in the last few days.


The 06z and 18z runs have not been similar to the more reliable 00z and 12z runs.
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786. auburn (Mod)
Quoting Bordonaro:


Look at #732..That Siberian Artic air, with daytime highs currently in the -60F range will be dumped into N America the week of Christmas. This may be a historic snow event for the SE US come 12-28 through 12-29-09.


Bring it on!!!I have an old 4X4 just waiting for it!!!
Member Since: Agosto 27, 2006 Posts: 546 Comments: 50550
785. xcool
auburn why ??.
Member Since: Septiembre 26, 2009 Posts: 2 Comments: 15626
Quoting xcool:
lmao


Look at #732..That Siberian Artic air, with daytime highs currently in the -60F range will be dumped into N America the week of Christmas. This may be a historic snow event for the SE US come 12-28 through 12-29-09. Look at the GFS model for 12-28-09 on link in comment 781..
Member Since: Agosto 25, 2009 Posts: 20 Comments: 6785
783. auburn (Mod)
Man the Doc sees me on here he is gonna ban me for sure...LOL
Member Since: Agosto 27, 2006 Posts: 546 Comments: 50550
Once in a Blue Moon
The sky shows aren't over yet. The Ursid meteor shower gets its turn December 22, the Pleiades will brighten up the night on December 29, and a blue moon will entertain New Year's Eve revelers. (And no, the moon doesn't turn a shade of turquoise: The phrase just means a second full moon appears in the same month. But don't let that stop you from singing its praises.)

End-of-Year Sky Show: Geminid Meteor Shower
By Jon Brooks, contributing writer, and Vera H-C Chan, Y! senior editor
Saturday, December 12, 2009
Member Since: Agosto 19, 2008 Posts: 32 Comments: 1918
Link

Link above is a 2 day, 4 map panel from GFS. Looks like a major snow storm for TX on 12-28-09.
Member Since: Agosto 25, 2009 Posts: 20 Comments: 6785
780. xcool
lmao
Member Since: Septiembre 26, 2009 Posts: 2 Comments: 15626
779. auburn (Mod)
Quoting xcool:
auburn comeon now .give little hope

Would be the first time ever I think...
Member Since: Agosto 27, 2006 Posts: 546 Comments: 50550
778. xcool
auburn comeon now .give little hope
Member Since: Septiembre 26, 2009 Posts: 2 Comments: 15626
GO FIGURE!

Cities With Best and Worst Tap Water

Excerpt:

Cities with the best water:

1. Arlington, TX
2. Providence, RI
3. Fort Worth, TX
4. Charleston, SC
5. Boston, MA
6. Honolulu, HI
7. Austin, TX
8. Fairfax County, VA
9. St. Louis, MO
10. Minneapolis, MN

Cities with the worst water:

1. Pensacola, FL
2. Riverside, CA
3. Las Vegas, NV
4. Riverside County, CA
5. Reno, NV
6. Houston, TX
7. Omaha, NE
8. North Las Vegas, NV
9. San Diego, CA
10. Jacksonville, FL
Member Since: Agosto 19, 2008 Posts: 32 Comments: 1918
776. xcool
yeah iknow
Member Since: Septiembre 26, 2009 Posts: 2 Comments: 15626
775. auburn (Mod)
Quoting xcool:




NO way!!!!
Member Since: Agosto 27, 2006 Posts: 546 Comments: 50550
Quoting xcool:



Yep, I should have added that it does bring in some snow a few days after Christmas (though I have a little more faith in Dec 22 results than I do in Dec 28 results, and not much in either.)
Member Since: Posts: Comments:
743 C cat

Tell me bro.. is there anyone on this planet that would be a credible source to you that didn't agree with you? What exactly would BE credible to you. No matter who posts what, you always find a way to dismiss it as junk. Do you think that the AP is in cahoots with someone.. and how aboiut the moderate scientists they had check their work? Not one shred of evidence has been presented at this point that gives any credence to the wild claims of the thieves who stole someone else's mail. The out of context attacks have been addressed and context explanations have been delivered.. I'm not the brightest bulb in the box, but try as I might, I cannot find anything other than stupid statements written to friends and colleagues. And, as I said, as Doctor Masters said, there ARE some questions, but it sure seems to me that they are not dodging them.. they are addressing them one at a time.

Like you, I realize that this stuff will be used to try and take our money away.. but that doesn't make the conclusions untrue.. it means that politicians will manipulate their info to serve their business masters. I've said it before, and was ignored, much as this will likely be.. the answer is reward green behavior, not punish the current status quo. No cap and trade, no carbon credits, no further burden upon our crippled economy. Subsidize none carbon introducing energies and reward those that use it and reduce their carbon footprint... again, IMO, reward, not tax is the answer.
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Flooding Sucks Big-Time.
I don't mind getting dumbest, most obvious post of the day award.
Mold, mildew, asthma, have to throw out many items, even canned foods (usually)...long-term and hazardous effects...no fun, and not a particuarly interesting weather event to track.
Member Since: Agosto 19, 2008 Posts: 32 Comments: 1918
18 Z GFS backs off on the snow for the N Gulf coast a bit, but brings in the cold for the 21st, 22nd. For the FL peninsula, 0 C line south of Tampa ?!? with some light precip north of there...



GFS has been real insistent that someone along the gulf coast is going to get some snow, though, this is lightest bit of snow it has come up with in the last few days.
Member Since: Posts: Comments:
770. xcool


Member Since: Septiembre 26, 2009 Posts: 2 Comments: 15626
769. auburn (Mod)
Quoting atmoaggie:
You two on the south shore can have it. I really didn't need to 2 inches I got...



Had my share here in Bama also...and its just getting started here they say
Member Since: Agosto 27, 2006 Posts: 546 Comments: 50550
Quoting BahaHurican:
742. Astro.....
Will not quote the entire thing, but this is a really good post on tropical weather. I am thinking this could be a very busy year for the Southern Hemisphere, especially the SPac, due to the el nino currently in place and according to reports, strengthening.

Also,

755. AwakeInMaryland 6:02 PM EST on December 12, 2009
Good post also. I think people often confuse weather and climate and treat them as synonymous. Because climate describes a long-term state, the TYPICAL weather, what one can expect will likely occur, a climate SHIFT could potentially be devastating. I'm thinking of two historical examples right off the top of my head:

1. the Mayan "demise". There is considerable evidence to suggest that the decline of the Mayan civilization occurred, not because of the overthrow of its political structure, but because of a shift in weather patterns which meant growing / harvesting periods could no longer be predicted by the intelligentsia of the day.

2. the so-called "Anasazi", who abandoned their cliff dwellings in the NM / AZ / CO area [allegedly] because of a climate shift which resulted in severe drought conditions. By the time the Pueblo Indians wanted to go back, they were "enclosed" by the Spanish into pueblos...

This is why some of us really don't care whether GW is AGW or non-AGW. We understand that human societies which are not prepared to adjust to a climate shift often falter and sometimes die out.

Remember the example of Joseph's dreams, which foretold the famine that brought the Israelites to Egypt. Preparation was why the Egyptians survived.


You mean we had climate change (per you're FEW examples) before Man-made cc , now thats interesting
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1. the Mayan "demise". There is considerable evidence to suggest that the decline of the Mayan civilization occurred, not because of the overthrow of its political structure, but because of a shift in weather patterns which meant growing / harvesting periods could no longer be predicted by the intelligentsia of the day.

2. the so-called "Anasazi", who abandoned their cliff dwellings in the NM / AZ / CO area [allegedly] because of a climate shift which resulted in severe drought conditions. By the time the Pueblo Indians wanted to go back, they were "enclosed" by the Spanish into pueblos...


Fantastic examples! Oh, I've been so lucky and blessed to have seen both (note to self: put on gratitude list)...

Everyone, I hope you will put on your "bucket lists."

That wandering in the desert for 40 years thing, though...not so good. Men too proud to ask for directions!
Member Since: Agosto 19, 2008 Posts: 32 Comments: 1918
You two on the south shore can have it. I really didn't need to 2 inches I got...

Member Since: Posts: Comments:
742. Astro.....
Will not quote the entire thing, but this is a really good post on tropical weather. I am thinking this could be a very busy year for the Southern Hemisphere, especially the SPac, due to the el nino currently in place and according to reports, strengthening.

Also,

755. AwakeInMaryland 6:02 PM EST on December 12, 2009
Good post also. I think people often confuse weather and climate and treat them as synonymous. Because climate describes a long-term state, the TYPICAL weather, what one can expect will likely occur, a climate SHIFT could potentially be devastating. I'm thinking of two historical examples right off the top of my head:

1. the Mayan "demise". There is considerable evidence to suggest that the decline of the Mayan civilization occurred, not because of the overthrow of its political structure, but because of a shift in weather patterns which meant growing / harvesting periods could no longer be predicted by the intelligentsia of the day.

2. the so-called "Anasazi", who abandoned their cliff dwellings in the NM / AZ / CO area [allegedly] because of a climate shift which resulted in severe drought conditions. By the time the Pueblo Indians wanted to go back, they were "enclosed" by the Spanish into pueblos...

This is why some of us really don't care whether GW is AGW or non-AGW. We understand that human societies which are not prepared to adjust to a climate shift often falter and sometimes die out.

Remember the example of Joseph's dreams, which foretold the famine that brought the Israelites to Egypt. Preparation was why the Egyptians survived.
Member Since: Posts: Comments:
Quoting Bgoney:
regular variations over a period of years, hence change.

NICE "Spin"! You could get a job downtown; lots of lobbyists, PR firms.
I'm not knocking that...mind you; pls. send "Finders Fee" soonest :)
Member Since: Agosto 19, 2008 Posts: 32 Comments: 1918
761. ROFL; yeah, and I have two ferocious ankle-biters, too!
Member Since: Agosto 19, 2008 Posts: 32 Comments: 1918
regular variations over a period of years, hence change.
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the quote neighbor the quote :D you to close to dis ;)
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Quoting VAbeachhurricanes:
755. sometimes i think alot of people here say things just to say them...

Yo, neighbor...are you dissin' me or the "quote"? lol

I can't help myself, I'm a literalist, except when I see symbolism...as usual, I'm beside myself (j/k sun sign is Gemini).

Closer; no cigar!

weath·er (wr)
n.
1. The state of the atmosphere at a given time and place, with respect to variables such as temperature, moisture, wind velocity, and barometric pressure.
2.
a. Adverse or destructive atmospheric conditions, such as high winds or heavy rain: encountered weather five miles out to sea.
b. The unpleasant or destructive effects of such atmospheric conditions: protected the house from the weather.
3. weathers Changes of fortune: had known him in many weathers.
v. weath·ered, weath·er·ing, weath·ers
v.tr.
1. To expose to the action of the elements, as for drying, seasoning, or coloring.
2. To discolor, disintegrate, wear, or otherwise affect adversely by exposure.
3. To come through (something) safely; survive: weather a crisis.
4. To slope (a roof, for example) so as to shed water.
5. Nautical To pass to the windward of despite bad weather.
v.intr.
1. To show the effects, such as discoloration, of exposure to the elements: The walls of the barn had weathered.
2. To withstand the effects of weather: a house paint that weathers well.
adj.
1. Nautical Of or relating to the windward side of a ship; windward.
2. Relating to or used in weather forecasting: a weather plane.
Phrasal Verb:
weather in
To experience or cause to experience weather conditions that prevent movement: The squadron is weathered in because of dense fog. Such a storm will weather the fleet in.
Idioms:
make heavy weather of
To exaggerate the difficulty of something to be done.
under the weather
1. Somewhat indisposed; slightly ill.
2. Slang
a. Intoxicated; drunk.
b. Suffering from a hangover.
[Middle English weder, wether, from Old English weder; see w- in Indo-European roots.]

The American Heritage® Dictionary of the English Language, Fourth Edition copyright ©2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.
weather [ˈwɛðə]
n
1. (Earth Sciences / Physical Geography)
a. the day-to-day meteorological conditions, esp temperature, cloudiness, and rainfall, affecting a specific place Compare climate [1]
b. (modifier) relating to the forecasting of weather a weather ship
2. a prevailing state or condition
make heavy weather
a. (Transport / Nautical Terms) (of a vessel) to roll and pitch in heavy seas
b. (foll by of) to carry out with great difficulty or unnecessarily great effort
under the weather Informal
a. not in good health
b. intoxicated
adj
(Transport / Nautical Terms) (prenominal) on or at the side or part towards the wind; windward the weather anchor Compare lee [4]
vb
1. (Earth Sciences / Physical Geography) to expose or be exposed to the action of the weather
2. (Earth Sciences / Physical Geography) to undergo or cause to undergo changes, such as discoloration, due to the action of the weather
3. (Earth Sciences / Physical Geography) (intr) to withstand the action of the weather
4. (when intr, foll by through) to endure (a crisis, danger, etc.)
5. (Fine Arts & Visual Arts / Architecture) (tr) to slope (a surface, such as a roof, sill, etc.) so as to throw rainwater clear
6. (Transport / Nautical Terms) (tr) to sail to the windward of to weather a point
[Old English weder; related to Old Saxon wedar, Old High German wetar, Old Norse vethr]
weatherability n
weatherer n

Collins English Dictionary – Complete and Unabridged 6th Edition 2003. © William Collins Sons & Co. Ltd 1979, 1986 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003
weather (wthr)
The state of the atmosphere at a particular time and place. Weather is described in terms of variable conditions such as temperature, humidity, wind velocity, precipitation, and barometric pressure. Weather on Earth occurs primarily in the troposphere, or lower atmosphere, and is driven by energy from the Sun and the rotation of the Earth. The average weather conditions of a region over time are used to define a region's climate.

The American Heritage® Science Dictionary Copyright © 2005 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.
Member Since: Agosto 19, 2008 Posts: 32 Comments: 1918
i said that because antartic sea ice forms at a higher altitude than artic, therefore increased sun angle, and meaning more energy is deflected

I'm pretty sure they both form at sea level. ;)

(and yes, I know it was probably a typo - just thought it was funny)
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755. sometimes i think alot of people here say things just to say them...
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Quoting VAbeachhurricanes:


but dude... we gotta stop it! 75 degrees 24/7!!

I want to live where you're livin
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Quoting Bgoney:
Don't you guys see the irony in the title of this topic. "The climate is changing" , you gotta read that and laugh, don't you , I mean you do know that the word climate means CHANGE . This is hilarious.


I really wanted to give you the benefit of the doubt...but that's not what I'm seeing that in the Latin/Greek roots. Maybe "weather"? Will get back to you after I look up roots of that!

Guess you can tell hubby isn't taking ME out on a Saturday night. Leftovers and Netflix, whoo hoo!

cli·mate (klmt)
n.
1. The meteorological conditions, including temperature, precipitation, and wind, that characteristically prevail in a particular region.
2. A region of the earth having particular meteorological conditions: lives in a cold climate.
3. A prevailing condition or set of attitudes in human affairs: a climate of unrest.
[Middle English climat, from Old French, from Late Latin clima, climat-, from Greek klima, surface of the earth, region; see klei- in Indo-European roots.]

The American Heritage® Dictionary of the English Language, Fourth Edition copyright ©2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.
climate [ˈklaɪmɪt]
n
1. (Earth Sciences / Physical Geography) the long-term prevalent weather conditions of an area, determined by latitude, position relative to oceans or continents, altitude, etc.
2. (Earth Sciences / Physical Geography) an area having a particular kind of climate
3. a prevailing trend or current of feeling the political climate
[from Late Latin clima, from Greek klima inclination, region; related to Greek klinein to lean]
climatic [klaɪˈmætɪk], climatical, climatal adj
climatically adv
Usage: Climatic is sometimes wrongly used where climactic is meant. Climatic is properly used to talk about things relating to climate; climactic is used to describe something which forms a climax

Collins English Dictionary – Complete and Unabridged 6th Edition 2003. © William Collins Sons & Co. Ltd 1979, 1986 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003
climate (klmt)
The general or average weather conditions of a certain region, including temperature, rainfall, and wind. On Earth, climate is most affected by latitude, the tilt of the Earth's axis, the movements of the Earth's wind belts, the difference in temperatures of land and sea, and topography. Human activity, especially relating to actions relating to the depletion of the ozone layer, is also an important factor.

The American Heritage® Science Dictionary Copyright © 2005 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


Member Since: Agosto 19, 2008 Posts: 32 Comments: 1918
Quoting Bgoney:
Don't you guys see the irony in the title of this topic. "The climate is changing" , you gotta read that and laugh, don't you , I mean you do know that the word climate means CHANGE . This is hilarious.


but dude... we gotta stop it! 75 degrees 24/7!!
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Don't you guys see the irony in the title of this topic. "The climate is changing" , you gotta read that and laugh, don't you , I mean you do know that the word climate means CHANGE . This is hilarious.
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Quoting reedzone:
Evening everyone..
The GFS is consistent in brining a southern snowstorm right after Christmas. Also it's been consistent of bringing very cold weather a few dasy before Christmas, the 540 line crossing Orlando, Florida. With the given pattern and predictions of this winter, accumulating snow in Florida is a slight chance. It's gonna be an interesting few weeks. I can see Long Island having a White Christmas along with Boston, maybe even DC. Somethings not right with the clipper the GFS is showing, I think it could be bigger and possibly one of those quick heavy snow/wind storms. We'll see I guess..


Just to clarify something here..
When I said snow in Florida, I meant sometime this winter, not with the predicted cold blast. Snow (accumulating) in Florida THIS WINTER is a slight chance.
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Later JF,,my cue to split just arrived.

And it aint here..LOL
Member Since: Julio 3, 2005 Posts: 421 Comments: 127702
Quoting atmoaggie:

1. Because we are closer to the sun during the Southern hemisphere summer? Or some other mechanism you are referring to?
2. Reflecting solar energy is reflecting solar energy. Reflecting more of a higher input as a cooling mechanism? I don't think so. And albedo of 0.9 means than 90% of incoming is reflected (or not absorbed). A higher incoming value? Well, 10% of a higher number is a higher number, too.
This is further complicated by angle of incidence. I will grant you that.


Yes, ozone is a potent GHG. And by not absorbing the UV as much in the stratosphere through an exothermic reaction, temps when the hole is present are lower at those levels.
But, the ozone hole is only present for as long as the polar stratospheric clouds are, which is for the first 2 to 3 months after sunlight reappears there. At the surface during this time the angle of incidence is very high. By the time of summer solstice, the ozone hole is usually either closed back up completely or very nearly so. So the lack of ozone for a couple of months after the sun first reappears at stratospheric levels lead to less GHG-functioning ozone when the sun is hardly reaching the surface. The rest of the year, there is no ozone hole, including the entire austral summer.

Not saying it would have no effect, just that when the effect would be greatest, it doesn't happen.


atmo i said that because antartic sea ice forms at a higher altitude than artic, therefore increased sun angle, and meaning more energy is deflected. 2. yes, put 90% of one would split it inot .9 and .1, 90% of 2 splits it into 1.8 and .2. a huge difference.
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748. auburn (Mod)
Quoting Patrap:
Ill say..wow,some small Hail here now


I have Sleet...LOL
Member Since: Agosto 27, 2006 Posts: 546 Comments: 50550
Evening everyone..
The GFS is consistent in brining a southern snowstorm right after Christmas. Also it's been consistent of bringing very cold weather a few dasy before Christmas, the 540 line crossing Orlando, Florida. With the given pattern and predictions of this winter, accumulating snow in Florida is a slight chance. It's gonna be an interesting few weeks. I can see Long Island having a White Christmas along with Boston, maybe even DC. Somethings not right with the clipper the GFS is showing, I think it could be bigger and possibly one of those quick heavy snow/wind storms. We'll see I guess..
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Im glad I dont see all the posts the way my filter is set.

LOL

Cuz..I'd be laughing so hard my colon could bark.
Member Since: Julio 3, 2005 Posts: 421 Comments: 127702
Ill say..wow,some small Hail here now
Member Since: Julio 3, 2005 Posts: 421 Comments: 127702
Quoting indianrivguy:
Review: E-mails show pettiness, not fraud

Climate experts, AP reporters go through 1,000 exchanges

LONDON - E-mails stolen from climate scientists show they stonewalled skeptics and discussed hiding data — but the messages don't support claims that the science of global warming was faked, according to an exhaustive review by The Associated Press.

The 1,073 e-mails examined by the AP show that scientists harbored private doubts, however slight and fleeting, even as they told the world they were certain about climate change. However, the exchanges don't undercut the vast body of evidence showing the world is warming because of man-made greenhouse gas emissions.

The scientists were keenly aware of how their work would be viewed and used, and, just like politicians, went to great pains to shape their message. Sometimes, they sounded more like schoolyard taunts than scientific tenets.

The scientists were so convinced by their own science and so driven by a cause "that unless you're with them, you're against them," said Mark Frankel, director of scientific freedom, responsibility and law at the American Association for the Advancement of Science. He also reviewed the communications.

Frankel saw "no evidence of falsification or fabrication of data, although concerns could be raised about some instances of very 'generous interpretations.'"

This article supports Doc Masters position on the stolen emails. It shows there was no great conspiracy to defraud, but some questions are warranted

Million words reviewed
The AP studied all the e-mails for context, with five reporters reading and rereading them — about 1 million words in total.

One of the most disturbing elements suggests an effort to avoid sharing scientific data with critics skeptical of global warming. It is not clear if any data was destroyed; two U.S. researchers denied it.

The e-mails show that several mainstream scientists repeatedly suggested keeping their research materials away from opponents who sought it under American and British public records law. It raises a science ethics question because free access to data is important so others can repeat experiments as part of the scientific method. The University of East Anglia is investigating the blocking of information requests.

I think that much has been made of the refusal/stonewalling of the FOI act, but read this;

The e-mails also show how professional attacks turned very personal. When former London financial trader Douglas J. Keenan combed through the data used in a 1990 research paper Jones had co-authored, Keenan claimed to have found evidence of fakery by Jones' co-author. Keenan threatened to have the FBI arrest University at Albany scientist Wei-Chyung Wang for fraud. (A university investigation later cleared him of any wrongdoing.)

I can see why one would not want to release any info to an antagonist..

"I do now wish I'd never sent them the data after their FOIA request!" Jones wrote in June 2007.

In another case after initially balking on releasing data to a skeptic because it was already public, Lawrence Livermore National Lab scientist Ben Santer wrote that he then opted to release everything the skeptic wanted — and more. Santer said in a telephone interview that he and others are inundated by frivolous requests from skeptics that are designed to "tie-up government-funded scientists."

There are two more pages to the article.. I don't wish to "stretch" the blog so I'll leave it as this. I think it is worth the read.

The one clear impression that I am getting from the information you have presented is that the reasons to doubt are all very real.

Quote..."no evidence of falsification or fabrication of data, although concerns could be raised about some instances of very 'generous interpretations.'" So generous interpretations are different from fraud. Neither of them is the truth.

or

Quote..."In another case after initially balking on releasing data to a skeptic because it was already public, Lawrence Livermore National Lab scientist Ben Santer wrote that he then opted to release everything the skeptic wanted — and more. Santer said in a telephone interview that he and others are inundated by frivolous requests from skeptics that are designed to "tie-up government-funded scientists."

I am very confused with that comment because I always thought that most scientists had computers and that the data was on computer files. How can a request for computer files even begin to equate with request of old where that data was only on paper??

The more we read about the explanations and excuses the more it becomes a joke.

Shame on them all.

Thanks for the post, we need more of that type of information sharing so that we can see them for the frauds they really are.



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It looks like a tornadic thunderstorm is heading for the NOLA area. Earlier posts depicted a hook-shaped cell heading for SE Louisiana.

The northern edge of the low in the Gulf (gulp, another Gulf low!) seems to be producing freezing rain. Northern Indiana could get freezing rain tonight, meaning we're next in S. Ontario. Earlier this morning, the Weather Network here predicted about 7 mm (0.3 in) of freezing rain for my location, but now they're predicting about 7 cm (3 in) of snow. The storm is expected to merge with the low near the Dakotas, an Alberta Clipper, by Sunday. Another storm, another week of unstable and erratic forecasts. The US weather map on one of the earlier posts depicts heavy snowsqualls here on Dec. 15 and 16, and it looks like we could tap into any or all of these bodies of water: Lake Huron, Georgian Bay, and Lake Superior. Currently the forecast predicts no snow on those two days, but that's probably because the probabilities are so uncertain, directly indicative of snowsqualls; the two days following are predicted to drop 10 cm (4 in) of snow.

Tropical Storm Cleo has apparently disapated, but not if you look at satellite imagery animations: since yesterday, the giant explosion of convection collapsed, and two circulations were absorbed into the main larger system. However, the collapsed convection is now restarting again, and it is heading straight for northern Madagascar. The entire system that was Cleo is protected by a giantic envelope that stretches north to 8N, west to the coast of Kenya, and east to the new tropical disturbance in the South Indian Ocean (future David), which by the way, flared up and organised rapidly in the past 24 hours. The only thing in the way of re-Cleo reorganising and hitting Madagascar is a small pocket of very dry air and 30kt shear. However, the new circulation of Cleo has a very strong anticyclone protecting it, and shear tendency west of the storm is dropping.




Meanwhile, in the North Indian Ocean, Ward exploded in intensity in the past 24 hours, and is now struggling from its low latitude and strong wind shear to its north. However, it too is a large system, with water vapor touching both ex-Cleo and the new South Indian Ocean system, joining both at the equator.

The third system, TC Four in the South Pacific, is also enormous in size: spanning an incredible 15 degrees in both longitude and latitude diameter. It is currently heading for Fiji as a tropical storm, likely to peak in intensity by then (remember that the 2009 Fiji floods earlier this year were caused by a smaller system, one that was only tropical depression strength that did not hit Fiji directly, yet broke a record for the wettest tropical cyclone on record in that country and killed 12 people). However, after that it is likely to follow the Southeast Pacific ICTZ--directly into the Humboldt current.




Granted, the storm is heading for dry air and an area of 80 kt shear. However, shear tendency in the area shows that shear is dropping appreciably ahead of the storm. Although it seems to be heading for colder water, the storm will then travel due east, absorbing moisture from the continous ICTZ. The storm is also so large that at least part of it will tap into moisture, warm water, and of course an area of lower shear. This may actually serve to move the storm circulation farther north, within the warm borderline waters of 25-26C.




Prevailing winds and the band of mositure mean that TC Four will not trek south of 30S. This means trouble, because the northern end, and the stronger side, of the cyclone will tap into the warm pool of water at the Central Pacific supporting El Nino (by the way, two types of El Nino were recently identified, as indicated in the Jaunary 2010 issue of Discover. One type is the familiar tounge of warm water from the coast of Peru. The other type however, emerging only in the past 30 years, possibly a product of global warming, and this one not affecting Atlantic tropical cyclone activity during, that caused above-average tropical cyclone activity in the 2004 Atlantic hurricane season and may have contributed to category 2 Catarina forming off Brazil in March, and the type that is currently prevalent, is a zone of warm water on the Central equatorial Pacific). This will bring that pool of warm water, in which 30C water extend as far east 150W, which, just yesterday, it did not. Most of this warmest water is ahead, and about 15 degrees north, of TC Four's predicted path. The pool of warm water tropical water is already located more in the east Pacific than in the west, and more in the Southern Hemisphere than in the North. Since the north side of TC Four will be circulating the warm water eastward, and toward the south ahead of the storm, bringing the pool of water farther east.

Current upper-level winds direct the storm north of 20S at around 125W. The SSTs at this location are currently 27C. When the storm hits 110W, if it is still active, it will run out of water to its north that is currently above 26C. At this point, the East Pacific ridge will be trying to force the storm south toward the Antarctic. By then, the strongest portion of the storm will be its northwestern side, as its eastern side will be corroded by wind shear, dry air, and the Humboldt Current. By then, according to current storm speeds, it should be close to December 21, when the winter solstice will place the sun almost directly over the latitude of that storm. After that, the only places left to go will be either toward Antarctica, or directly to the heart of the dying Humboldt.

The Humboldt has been retreating for three weeks now. Sometimes it would spring back up and force the pool of warm water into the Western Pacific, where it was only two days ago. But mostly, especially for the leading edge of the current's cold water, it has been retreating east and south. That's exactly what the stronger side of TC Four is expected to do for the next one-and-a-half weeks to the ocean surface thermoclines as the storm progresses eastward: force them east and south. Currently, the pool of warm water has 22C water extending as far as 96W, as far east as the western Gulf of Tehuantepec in Mexico, and barely farther west than Galveston, Texas. 18C water, meanwhile, only extends as far northwest as 78W and 22S. Off the coast at the border between Peru and Chile, the water temperatures are higher than 22C, while they are above 25C at the coast of Equador at the equator. Offshore the Galapagos Islands, they are 24C. A high pressure system protects the Current, sending cold water north and west on the high's eastern side.

Since 1945, no tropical cyclone in the South Pacific has made it past 125W, and only four have ever made their way east of 130W. When TC Four hits the East Pacific ridge, if it makes it that far, the circulation of the storm may force the ridge southward. The storm might then turn extratropical, becoming even larger and splitting into two, with one part tracking over West Antarctica and the other part heading for the Acatama Desert in Chile, on the north side of the high. Since this would be the beginning of the Antarctic summer, the extra warm water carried by the storm could threaten ice shelves. The northern storm could also cause the warm water already off the coast of Peru to join the small pool of warmth off the Acatama, cutting off the Humboldt's access to the tropics. The westerlies brought on by the storm could force the pool of warm water to move east, strengthening the Counter-Equatorial current and causing an enhanced El Nino, perhaps producing as much as 10C above normal SSTs at the equator.

The storm on the Australian coast is currently taping into 31C water, and is already a tropical depression. However, both it and David will be affected by the high pressure system west of Australia. With all these large storms forming worldwide, it looks like global ocean currents will change even more quickly than in the past two weeks. Also remember that Arctic sea ice has not grown for the past week, that it is close to setting another record for low extent for this time of year, and that this is unusual. With storms bringing warm, Southern hemisphere tropical water eastward, it looks like a strengthening of the Counter-Equatorial current is really in store for the Indian and Pacific ocean. The East Pacific low, typical of El Nino, is brining storms into California, as one made landfall last night.

The final system I'd like to bring attention to is an area of high vorticity off the coast of Uruguay. This area is located south of a small zone of very low vorticity, and north of another zone in ocean SSTs where very warm water (23C) lies only 300 km from an area of very cool water (12C). The two are heading toward each other almost head-on, and I think this will produce a strong storm in the area.

36 hours from now, I predict that there will be six tropical cyclones worldwide. If my scenario plays out as predicted, the world may be in for a very chaotic NHem winter/SHem summer. The root of this is El Nino, and that's not expected to peak until February.

Since global warming may be behind this state of self-modifying El Nino, it's definitely time to do something. First it was Nida, then the Indian Ocean storms, then TC Four. The Copenhagen Conference is about half past, and it's up to the world to show its voice on the subject.
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Id say the warm front jumped N of us..60F now with Heavy T-storms currently
Member Since: Julio 3, 2005 Posts: 421 Comments: 127702
Parts of Magazine St. near Here are going under seems
Member Since: Julio 3, 2005 Posts: 421 Comments: 127702

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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.

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