The big weather meeting

By: Dr. Jeff Masters , 17. tammikuuta 2007 klo 04:34 (GMT)

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Greetings from the annual meeting of the American Meteorological Society in San Antonio, Texas! At the world's largest gathering of meteorologists, the main topic of conversion has been--drum roll--the weather! Mostly, we�ve been grumbling about the nasty ice storm here, which has left city streets deserted and given the local school kids a holiday. Why couldn�t our record warm winter weather have lasted another week?! The large-scale weather pattern over the Northern Hemisphere has indeed changed to a decidedly wintery one, not only for North America, but northern Asia as well. Even Europe appears likely to get some real winter weather starting next week. I speculate that part of the reason for this shift is that the Arctic ice has finally frozen up enough to cut off the extra heat and moisture that was retarding formation of the usual cold Arctic air masses at the beginning of winter. Natural variability of the weather is probably the major factor, though.


Figure 1. Global departure of temperature from average for December 2006. Image credit: NCDC.

The other big topic of conversation has been the unbelievably warm winter we�ve had up until now. Talks I�ve attended given by meteorologists from both the U.S. and Europe have emphasized how unusual this winter was--and most of 2006. Take a look at the newly-released image (Figure 1) of the warmest December on record for the globe. The average global temperature for December 2006 was +0.72�C (+1.30�F) above normal, beating out 2003's record of +0.70�C/1.26�F, according to the National Climatic Data Center. Much of the U.S., Canada, Europe, and Siberia recorded their warmest December ever. Below normal temperatures were recorded in the Middle East and northern Africa, but over 80% of the world�s land areas were warmer than average--and not just a little above average! The swath of temperatures more than 5�C (9 �F) above average covering most of the world�s land mass north of 40� north latitude is unprecedented in size in the wintertime historical record, going back to at least 1900.

Record winter warmth in one part of the Northern Hemisphere is usually due to a sharp bend in the jet stream that creates a ridge of high pressure, allowing a warm southerly flow of air into the region. Adjacent regions have a compensating trough of low pressure that brings cold, northerly winds and below normal temperatures. This was certainly the case in January 2006, when the U.S. experienced its warmest January on record. Asia and Europe experienced a brutally cold January. Moscow hit -40�, its coldest temperature since 1979. Parts of Portugal saw their first snow since 1954. Siberia reached -70� F.

Enter December 2006. Again, record warmth was observed over the U.S. and Canada. A compensating cooler than normal area was present over the Gulf of Alaska and western Siberia, but it was very weak. There was almost no cold Arctic air present anywhere in the Northern Hemisphere, which is unprecedented in the historical record (going back at least 100 years). What�s the cause of this unusual pattern? Part of the blame probably rests with the late-freezing Arctic ice this year. More open water than ever recorded pumped abnormal heat and moisture into the air, retarding the formation of the usual cold air masses. At an interesting talk titled �Extremes and El Nino� given by Dr. Gerald Meehl of the National Center for Atmospheric Research today, he showed that both El Nino and increasing greenhouse gases are probably part of the reason, as well. He averaged together the wintertime temperature anomalies for El Nino events for the 1970s through 1990s, and came up with a plot that showed the typical pattern we expect--a warm winter over Canada and the northern U.S., and cold over Europe and Asia. Next, he showed a climate model simulation of a wintertime El Nino event run using the levels of greenhouse gases that we have now. The model simulation showed wintertime warmth extending into Asia and Europe during El Nino years, much like the pattern in Figure 1, thanks to the increase in greenhouse gases over the past 30 years.

In other talks I heard today, Dr. Roger Brugge of the University of Reading in England estimated that the record warm temperatures measured in parts of Europe this fall would be repeated only once in 5,000-10,000 years, unless climate change were to blame. Dr. Klaus Wolter of NOAA remarked, �We all know global change is occurring,� and went on to say, �the gun is starting to smoke�, when analyzing the persistent increasing trend in extremely warm events in the Northern Hemisphere.

One cannot blame a single weather event�or single warm year�on climate change. However, the unbelievably warm start to the winter of 2006-2007 is part of an unmistakable pattern that shows human-caused climate change is upon us.

Jeff Masters

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401. Ramblerbob
19. tammikuuta 2007 klo 22:16 (GMT)
We can't check solar output more than to just a few years ago so how do we know what solar output is? I don't mean just solar flare activity but the actual solar total output. It seems to me it would take a miniscule percentage change in total solar output to change our climate. There have been periods in earth's history (not just to ice core data times!) but to prehistoric times as well. At some point, for instance, a large percentage of the North American continent was covered by ocean. Was that caused by global warming? Was it caused by the activity of dinosaurs (methane maybe???)? Could the same process be happening now? Lets not just look at the last century (unfortunately we only have temp data for that period of time) or even 400,000 years but look at the whole historic picture and not be so short sighted (as we tend to be as humans who live less than a century (a VERY short time in an earth history perspective) !
400. weatherboykris
19. tammikuuta 2007 klo 16:08 (GMT)
new blog's up
Member Since: 9.12.2006 Posts: 125 Comments: 11346
398. weatherboykris
19. tammikuuta 2007 klo 16:04 (GMT)
Is that the KJV?'Silly' doesn't seem like a word you'd find in the Bible.
Member Since: 9.12.2006 Posts: 125 Comments: 11346
396. weatherboykris
19. tammikuuta 2007 klo 16:02 (GMT)
Sorry man but what we are doing to this planet is really stupid! The bible is correct! Man is silly!


I'm just wondering...what's with all the awkward language and the Bwhaha's?
Member Since: 9.12.2006 Posts: 125 Comments: 11346
394. weatherboykris
19. tammikuuta 2007 klo 15:53 (GMT)
You know CB, you'd be a good actor for a role as a bumbling villain who doesn't stop talking in a movie."Now I will destroy the world"Bwahaha!!!
Member Since: 9.12.2006 Posts: 125 Comments: 11346
393. weatherboykris
19. tammikuuta 2007 klo 15:52 (GMT)
Thanks skye,but Rmblerbob brought it up.Thanks for checking it out.
Member Since: 9.12.2006 Posts: 125 Comments: 11346
391. HIEXPRESS
19. tammikuuta 2007 klo 15:48 (GMT)
1977 Florida Freeze
from http://eyewall.met.psu.edu/ranking/ranking.html
Member Since: 13.10.2005 Posts: 4 Comments: 2155
388. Skyepony (Mod)
19. tammikuuta 2007 klo 15:43 (GMT)
Kris, you bring up interesting questions on the sun. & yes the little ice age seems to have been caused by a lack of solar activity.

But we aren't really experencing a big increase in solar activity right now...It was worse in the '60's

click to make bigger
more NASA graphics

Also as discussed in the last blog~ if it was inceased solar output the upper reaches & the surface would be warming at the same rate, which isn't the case.

Lets check out some ice core data back 400000 years ~how much CO2 is present to what the temp is...& notice the CO2 line going straight up in the end, way higher then in the last 400000 years. This looks like it may not be a fun experiment.

link

This was kind of funny, notice his graph & his research ends in 1991, he even notes some of his referance links don't contain all facts. In '91 he is saying the global warming is due to the sun & now the cooling trend has already begun, since we're cycling down. Notice it hasn't been updated (on the very bottom) since 1997, lol '98 was pretty warm. I'm suprised it was on the 1st page on a google search, I guess alot of people are using this really out of date info.
Member Since: 10.08.2005 Posts: 156 Comments: 36069
387. MisterPerfect
19. tammikuuta 2007 klo 15:39 (GMT)
30 Years ago today it snowed in Miami, FL

Check out this vintage clip:Miami Snowfall
Member Since: 1.11.2006 Posts: 71 Comments: 20123
386. HIEXPRESS
19. tammikuuta 2007 klo 15:37 (GMT)
I'm still waiting with interest to see how the weather shapes up for the Boston Marathon in mid April. Typically they get either a warm (bad) tailwind (good) or a cool (good) headwind (bad). El Nino favors warm. Cool (not freezing or snow) & little or a cross wind would be great.
Member Since: 13.10.2005 Posts: 4 Comments: 2155
384. weatherboykris
19. tammikuuta 2007 klo 15:29 (GMT)
But on to weather, it's looking like a couple snowstorms for the NE the next two weeks.
Member Since: 9.12.2006 Posts: 125 Comments: 11346
382. weatherboykris
19. tammikuuta 2007 klo 15:28 (GMT)
Kumbaya!


this is getting good.LOL
Member Since: 9.12.2006 Posts: 125 Comments: 11346
380. HIEXPRESS
19. tammikuuta 2007 klo 15:25 (GMT)
Kumbaya!
Member Since: 13.10.2005 Posts: 4 Comments: 2155
377. weatherboykris
19. tammikuuta 2007 klo 15:18 (GMT)
sorry Patrap
Member Since: 9.12.2006 Posts: 125 Comments: 11346
376. HIEXPRESS
19. tammikuuta 2007 klo 15:18 (GMT)
Old Sol is really pumping here in Central Florida today. I dare any cold air to try coming here. I triple-dog dare it.
Member Since: 13.10.2005 Posts: 4 Comments: 2155
374. weatherboykris
19. tammikuuta 2007 klo 15:14 (GMT)
Lighten up kris. 'trap offers keen practical insights in season.
Remember:
Before you criticize someone, you should walk a mile in their shoes.
That way, when you criticize them, you will be a mile away, and you will have their shoes.


I geuss your right.and LOL
Member Since: 9.12.2006 Posts: 125 Comments: 11346
373. HIEXPRESS
19. tammikuuta 2007 klo 15:13 (GMT)
Lighten up kris. 'trap offers keen practical insights in season.
Remember:
Before you criticize someone, you should walk a mile in their shoes.
That way, when you criticize them, you will be a mile away, and you will have their shoes.
Member Since: 13.10.2005 Posts: 4 Comments: 2155
372. weatherboykris
19. tammikuuta 2007 klo 14:59 (GMT)
PAtrap,do you ever post anything weather related?I mean,EVER?
Member Since: 9.12.2006 Posts: 125 Comments: 11346
370. Patrap
19. tammikuuta 2007 klo 14:00 (GMT)
Later.Im going back to Sex..er sleep..er resting..LOL!
Member Since: 3.07.2005 Posts: 414 Comments: 125530
368. ricderr
19. tammikuuta 2007 klo 13:57 (GMT)
sill no licorice....that first one was good.....for the first 30 seconds..then it was the same oveer and over..still..maybe the best superbowl song since mcmahon and the bears
Member Since: 27.06.2006 Posts: 667 Comments: 20113
367. Patrap
19. tammikuuta 2007 klo 13:55 (GMT)
This aint College.Plus..we on a Mission from God!
Member Since: 3.07.2005 Posts: 414 Comments: 125530
365. Patrap
19. tammikuuta 2007 klo 13:48 (GMT)
Only a Fool would Challenge a Jarhead..a New Orleanian Jarhead.So...there ya are!
Member Since: 3.07.2005 Posts: 414 Comments: 125530
364. ricderr
19. tammikuuta 2007 klo 13:46 (GMT)
ummm...pat...now i challenge you..i want to see your worst licorice post.....oh..and i want it utubed....LOL
Member Since: 27.06.2006 Posts: 667 Comments: 20113
363. Patrap
19. tammikuuta 2007 klo 13:45 (GMT)
This is the Way we Live..New Orleans Saints No. 1 on da Field!..
Member Since: 3.07.2005 Posts: 414 Comments: 125530
362. Patrap
19. tammikuuta 2007 klo 13:44 (GMT)
My worst post about licorice..would be admired above your Best Tube story..anyday!..LOL!
Member Since: 3.07.2005 Posts: 414 Comments: 125530
360. Patrap
19. tammikuuta 2007 klo 13:33 (GMT)
Your gonna need a BiggerTube!..
Member Since: 3.07.2005 Posts: 414 Comments: 125530
357. Patrap
19. tammikuuta 2007 klo 13:21 (GMT)
Member Since: 3.07.2005 Posts: 414 Comments: 125530
356. weatherboykris
19. tammikuuta 2007 klo 05:09 (GMT)
goodnight
Member Since: 9.12.2006 Posts: 125 Comments: 11346
355. weatherboykris
19. tammikuuta 2007 klo 04:57 (GMT)
The theory was,if I remember correctly, that in a period of increased sunspots the earth was warmer and in a period of decreased sunspots it was colder.This was supported by the fact that a dramatic decrease in sunspots was observed during the Little Ice Age.
Member Since: 9.12.2006 Posts: 125 Comments: 11346
354. weatherboykris
19. tammikuuta 2007 klo 04:56 (GMT)
You there?
Member Since: 9.12.2006 Posts: 125 Comments: 11346
353. weatherboykris
19. tammikuuta 2007 klo 04:51 (GMT)
Has anyone taken the time to figure out whether this might be due to an increase in the output of the sun? Hasn't there been global warm events much larger than this in the prehistoric past( before humans that is!!!)?


Well,yes and there are some theories(and some evidence to support them) that sunspots may be involved,but you try to take that to any serious meteorlogical meeting on global warming, and you'll get laughed out of the room.
Member Since: 9.12.2006 Posts: 125 Comments: 11346
352. Ramblerbob
19. tammikuuta 2007 klo 04:48 (GMT)
Has anyone taken the time to figure out whether this might be due to an increase in the output of the sun? Hasn't there been global warm events much larger than this in the prehistoric past( before humans that is!!!)?
351. weatherboykris
19. tammikuuta 2007 klo 04:11 (GMT)
SORRY I DIDN'T LISTEN TO YOUR ADMIN NOTICE!! sorry!


If you were talking to me...I was joking with the countdown.
Member Since: 9.12.2006 Posts: 125 Comments: 11346

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About JeffMasters

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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