2006: warmest year on record in the U.S.

By: Dr. Jeff Masters , 9:18 PM GMT on January 09, 2007

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The United States recorded its warmest year ever in 2006, according to today's report issued by the National Climatic Data Center (NCDC). The 2006 annual average temperature was 55�F, 2.2�F (1.2�C) above the 20th Century mean and 0.07�F (0.04�C) warmer than the previous warmest year, 1998. The NCDC had estimated that 2006 would be the 3rd warmest year in U.S. history last month, but an unusually warm December pushed 2006 to the top. It was the warmest December on record in the Northeast U.S., and the 4th warmest December for the country as a whole. Only 1939, 1957, and 1933 had warmer Decembers. However, the statistics partially hide the extraordinary warmth that began on December 10 and continued until January 6, when New York City tied their all-time record January high temperature of 72�. During the month ending January 6, the Northeast was 14 �F above average, and the U.S. as a whole was 7� above average.



No cause for alarm?
"No cause for alarm. Enjoy it while you have it," said Mike Halpert, head of forecast operations at the National Oceanic & Atmospheric Administration's Climate Prediction Center, in a story run by CNN just before New York City's record warmth. The story continued, "The weather is prone to short-term fluctuations, and forecasters said the mild winter does not necessarily mean global warming is upon us. In fact, the Plains have been hit by back-to-back blizzards in the past two weeks." True, the weather across most of the U.S. has finally cooled off this week, and the rest of January should have near average temperatures. And I agree that one warm month of winter in one country in its warmest year in 112 years of record keeping is not evidence of global warming, particularly when there is a moderate El Nino episode going on. An El Nino can lead to significantly warmer winters in the U.S.--exceptional December warmth has also occurred in 1877, 1939, and 1957, all of which were moderate or strong El Nino years. I've plotted up a comparison of temperatures in December of 1957 vs 2006 (Figure 1), and one can see that the unusual warmth of December 2006 does have historical precedent. Taking a look at average U.S. December temperatures for all years in the historical record (Figure 2), we see that these temperatures do show quite a bit of noise, and there is no evidence of dramatic warming in the past 30 years.


Figure 1. Comparison of the departure of average temperature from normal for December 1957 (the the second warmest December on record in the U.S.) and December 2006. Image credit: NOAA.

Figure 2. Average December temperatures for the U.S. from 1895 to 2006. Image credit: National Climatic Data Center.

Rolling thirteens with the weather dice
Take a look at the trend December temperatures in Figure 2. It shows that the average temperature has warmed a little more than 1� F in the past century. It may not seem like much, but that is enough to significantly load the dice in favor of warmer winters. Six of the ten warmest U.S. winters on record have occurred in the past 15 years. Month long spells where winter is seemingly absent--as also occurred in January 2006, the warmest January in U.S. history--have become more common. Keep in mind that the weather of January of 2006--which blew away the previous record for warmest January by a huge margin (2� F)--occurred during a La Nina year, not an El Nino. What concerns me most is that the warming trend is not isolated to the U.S. The 1� F rise in temperatures the past century has occurred world-wide, thanks to global warming, and the temperature increase has been much higher in the Arctic--something the climate models have predicted would occur as a telltale sign of the human-caused addition of greenhouse gases to the atmosphere. In the past, an exceptionally warm winter month in the U.S., like December 1957 (Figure 3), was offset by much cooler weather elsewhere, such as we see in Alaska, Greenland, and northern Siberia. However, December 2006 had no such offsetting cool temperatures--it was more than 1� C above average over almost all the land areas of the Northern Hemisphere north of 40� north latitude (Figure 4). Colorado, whose three blizzards have been widely cited as evidence that winter has been severe elsewhere, still recorded temperatures about 1� C above normal in December 2006.


Figure 3. Global departure of temperature from average for December 1957, the second warmest December on record in the U.S. Note that the exceptionally warm temperatures over the U.S. are offset by much cooler weather elsewhere, such as in Alaska, Greenland, and northern Siberia.

Figure 4. Global departure of temperature from average for December 2006. Note that the almost the entire globe north of 40� north latitude was more than 1� C above average, with large areas more than 6� C (11� F) above average.

All this unusual heat in the northern high latitudes is going to significantly slow down the formation of ice over the Arctic Ocean this winter. Furthermore, the lack of the usual snows across the Arctic may allow the snowpack to melt much earlier than normal in spring, resulting in more record warmth in the Arctic this summer. Arctic sea ice coverage, already down 20% in the past 20 years, is likely to continue to shrink in 2007. As sea ice melts in response to rising temperatures, it creates a positive feedback loop: melting ice means more of the dark ocean is exposed, allowing it to absorb more of the sun's energy, further increasing air temperatures, ocean temperatures, and ice melt. The observed changes in the ice cover (Figure 5) indicate that this feedback is now starting to take hold, and the weather dice will continue to get more loaded towards rolling higher numbers in 2007. I do think we're due for a cold winter next year--part of the warmth of the past two winters is probably due to the normal random fluctuations in the weather, and Nature has been rolling twelves more often than snake eyes of late. However, we're not going to see snake eyes too much more. December's weather in the Northeast U.S. may have been a case of the weather dice coming up thirteen--weather not seen on the planet since before the Ice Age began, 118,000 years ago. The weather dice will start rolling an increasing number of thirteens in coming years, and an ice-free Arctic Ocean in summertime by 2040 is a very real possibility, as indicated by computer modelling studies published in the Journal of Geophysical Research last month. This possibility is cause for alarm, and I, for one, had a lot of trouble enjoying the phenomenally warm weather of the past month here in Michigan.


Figure 5. Percent change in coverage of Arctic sea ice in Decembers from 1979-2006, compared to the 1979-2000 average. The Polar Ice Cap has shrunk by about 15% in December, and 20% in summer, over the past 20 years. Image credit: National Snow and Ice Data Center.

Check out the realclimate.org post on this winter's anomalous warmth.

I'll be back Thursday afternoon or Friday with a look at the status of El Nino. Will it still be around during hurricane season?

Jeff Masters

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549. weatherboykris
4:23 PM GMT on January 11, 2007
Yes,Skye they have been inconsistent.
Member Since: December 9, 2006 Posts: 125 Comments: 11346
548. Skyepony (Mod)
4:11 PM GMT on January 11, 2007
catastropheadjuster~ Long time... I think El Nio has peaked, it's heading toward neutral. Interesting is that a little more than 1/2 the models think after it gets to or near nuetral that it will go right back up into el nio for the worst of the cane season. I find this hard to buy at this time since the long range ENSO models aren't any good. Last years consensis of La Nia for 'cane season never panned & the consensis several months ago was ENSO wasn't moving toward neutral during the winter & spring.
Member Since: August 10, 2005 Posts: 161 Comments: 37197
547. weatherboykris
4:07 PM GMT on January 11, 2007
If I'm correct, his tunnels are horizontal.
Member Since: December 9, 2006 Posts: 125 Comments: 11346
546. weatherboykris
4:05 PM GMT on January 11, 2007
It is different.
Member Since: December 9, 2006 Posts: 125 Comments: 11346
544. weatherboykris
3:59 PM GMT on January 11, 2007
Well Good Morning everyone. I just thought I'd see what everyone thinks about Elnino and if it might be leaving? There's not to many people on much anymore not like hurricane season i really like reading what everyone says. Hope everyone has a safe day. I'll be sitting back reading everyone entries.

There are a lot more people during the hurricane season.If this were August, we'd be using a page per half-hour.
Member Since: December 9, 2006 Posts: 125 Comments: 11346
543. HurricaneMyles
3:09 PM GMT on January 11, 2007
It's been brought up snotly, and they're almost completely different then buster's idea.
Member Since: January 12, 2006 Posts: 5 Comments: 827
542. snotly
3:03 PM GMT on January 11, 2007
cyclone keeps talking about tunnels someone said that there was no basis in fact behind these tunnels but in fact there is:

See
Link
Member Since: Posts: Comments:
541. HurricaneMyles
2:46 PM GMT on January 11, 2007
Buster, everytime some gives you genuine advice to help your idea along you brush it off your shoulder.

Serouisly, no one here can help you. We cant get you funded even if we did support your idea. So spamming here is not helping your idea, its only making people more resistant to it.

So if you really want to try and get the tunnels built then you should do what caffinehog says.

"Get a formal education in climatology or some other weather-based degree. (Best would be a degree in climatology AND some other meteorogical degree)
Become a graduate student, (and you may have to become a professor before performing the next step,)
Write a grant proposal, and get funded.
Build a working model, and evaluate its effectiveness and impacts. (Not a computer model, a full scale model)
Get published in a peer-reviewed journal.
Bring it to the attention of the politicians who can fund it, and while you're at it, convince the US to break several international treaties barring weather modification.
THEN you can build your tunnels."
Member Since: January 12, 2006 Posts: 5 Comments: 827
540. catastropheadjuster
2:31 PM GMT on January 11, 2007
Well Good Morning everyone. I just thought I'd see what everyone thinks about Elnino and if it might be leaving? There's not to many people on much anymore not like hurricane season i really like reading what everyone says. Hope everyone has a safe day. I'll be sitting back reading everyone entries.
Member Since: Posts: Comments:
537. hurricane23
9:12 AM EST on January 11, 2007
Over all they expect that a Kelvin Wave may spark up warm anomalies in the coming weeks.

Visit here for current conditions and expert discussions.
Member Since: May 14, 2006 Posts: 8 Comments: 13621
535. hurricane23
9:04 AM EST on January 11, 2007
Joe Bastardi says Winter is going to come back with a vengeance...

"Those who think that winter 2006-2007 is going to remain mild are in for a shock," said Bastardi. "Winter is likely to come with a vengeance. A week from now, we'll start seeing truly cold air across much of the country, and we expect this change to last."

For more visit accuweather.
Member Since: May 14, 2006 Posts: 8 Comments: 13621
534. Patrap
8:03 AM CST on January 11, 2007
If a Fractional..Craig Super cant do it.It cant an will never be done.Quit torturing the Blog.Its not pretty to watch...
Member Since: July 3, 2005 Posts: 419 Comments: 127381
533. Patrap
8:01 AM CST on January 11, 2007
It too early for nonsense...The Big Storm Gathering in The west is going to Cause problems Come Fri-Sun..GFSx Link
Member Since: July 3, 2005 Posts: 419 Comments: 127381
531. Patrap
7:54 AM CST on January 11, 2007
7
Member Since: July 3, 2005 Posts: 419 Comments: 127381
529. hurricane23
8:40 AM EST on January 11, 2007
Good morning,

El Nio conditions are likely to continue through March-May 2007.


Most of the statistical and coupled models, including the NCEP Climate Forecast System (CFS), indicate that SST anomalies are near their peak and that decreasing anomalies are likely during February-May 2007 (Fig. 5). Recent observed trends in the upper ocean tend to support those forecasts. Decreasing upper-ocean heat content in the central equatorial Pacific has been progressing east in association with the upwelling portion of the most recent Kelvin wave. In the absence of any further Kelvin wave activity, the upper-ocean heat content should return to near average in a few months. However, there is considerable uncertainty in this outlook, given the resurgence of MJO activity in late December 2006. It is possible that the enhanced precipitation phase of the MJO, which is currently entering the western tropical Pacific, might trigger a more persistent pattern of cloudiness and precipitation over the anomalously warm waters of the central equatorial Pacific during the next several weeks. If that occurs, then the equatorial easterlies over the central Pacific will likely weaken possibly leading to the initiation of a fifth Kelvin wave.

CPC UPDATE HERE
Member Since: May 14, 2006 Posts: 8 Comments: 13621
528. orionRider
08:41 GMT le 11 janvier 2007
Hi anvil,
Still there, on and off..

Somebody know about comets? Why is it that on my picture the tail is long and narrow while it is rather triangular on other picts I've seen?

jeffB:
I took the pict with my wife's compact Kodak, set to 'green smile' ;-)
Guess it had to be something like 1/60th and f6.3, largest opening available at 3x zoom. I was very lucky the sun was blocked by the heavy clouds.
Member Since: Posts: Comments:
527. anvilhead
8:39 AM GMT on January 11, 2007
hello orion if youre still there.
Member Since: Posts: Comments:
526. orionRider
08:36 GMT le 11 janvier 2007
Yesterday 55F and today 120kph winds. Weather is wrecked. It's all the comet's fault...

My own comet...
Member Since: Posts: Comments:
525. anvilhead
7:57 AM GMT on January 11, 2007
hello caffiene
Member Since: Posts: Comments:
524. Caffinehog
7:17 AM GMT on January 11, 2007
Cyclone, if you want to build your tunnels you'll have to do this:
Get a formal education in climatology or some other weather-based degree.
Become a graduate student, (and you may have to become a professor before performing the next step,)
Write a grant proposal, and get funded.
Build a working model, and evaluate its effectiveness and impacts.
Get published in a peer-reviewed journal.
Bring it to the attention of the politicians who can fund it, and while you're at it, convince the US to break several international treaties barring weather modification.
THEN you can build your tunnels.

You can't just talk in a forum and write e-mails. That's the sign of somebody that does not know how to get something done, or isn't willing to do the work that it takes to do it. Who's going to follow somebody like that?
Nobody.

If you really want to accomplish this, you've got to do what it takes. And sitting here going on and on about it isn't what it takes.
Member Since: June 5, 2003 Posts: 0 Comments: 40
523. jeffB
4:31 AM GMT on January 11, 2007
Patrap, I'm happy that you were able to make lots of money with your Hale-Bopp photos, but look at the link I posted. McNaught reached a lower magnitude, i.e. a higher brightness, than Hale-Bopp ever did. But your photos of Hale-Bopp will remain more impressive, because that comet appeared against a dark sky. Just look at the number of background stars in your picture, and compare it to the lack of stars in any of the McNaught images. Also, I don't know if you still have a record of the exposure you used for Hale-Bopp, but I'll guarantee it was longer than the 1/2 to 1/20 sec people have been using for McNaught. I caught a recognizable (but blurry -- no tripod) image of McNaught with a 1/40 sec exposure at f/5.6! That's bright!
Member Since: Posts: Comments:
519. lightning10
4:14 AM GMT on January 11, 2007
Things are looking very interesting for So Cal.

While this weather system is not expected to produce a lot of
precipitation... it will likely bring very low snow levels to the
region. Initially... snow levels are expected to lower to between
4000 and 5000 feet by Thursday afternoon... lowest across northern
mountain ranges. Snow levels are expected to rapidly lower to around
1500 feet late Thursday night into Friday morning... with snow
flurries possibly down to 1000 feet. While any snow accumulation in
the foothills and valleys is expected to be minimal... the mountains
could experience a few inches of new snow with this very cold and
unsettled weather pattern. Major roadways that could be impacted by
the very low snow levels include Interstate 5 from the Grapevine to
Santa Clarita... Interstate 14 through the Soledad Canyon... Highway
33 in Ventura County...
Member Since: November 24, 2005 Posts: 41 Comments: 630
517. weatherboykris
3:55 AM GMT on January 11, 2007
goodnight CB
Member Since: December 9, 2006 Posts: 125 Comments: 11346
514. weatherboykris
3:01 AM GMT on January 11, 2007
I'll be back
Member Since: December 9, 2006 Posts: 125 Comments: 11346
513. weatherboykris
2:43 AM GMT on January 11, 2007
I'm back
Member Since: December 9, 2006 Posts: 125 Comments: 11346
508. weatherboykris
1:58 AM GMT on January 11, 2007
be back later
Member Since: December 9, 2006 Posts: 125 Comments: 11346
505. weatherboykris
1:54 AM GMT on January 11, 2007
We saw it already CB.Thanks
Member Since: December 9, 2006 Posts: 125 Comments: 11346
502. weatherboykris
1:41 AM GMT on January 11, 2007
good point STL,I liked your blog too
Member Since: December 9, 2006 Posts: 125 Comments: 11346
501. weatherboykris
1:40 AM GMT on January 11, 2007
The fact is,unless Bill Gray is in disguise here...there are no proffesional meteorologists at WU
Member Since: December 9, 2006 Posts: 125 Comments: 11346
499. weatherboykris
1:36 AM GMT on January 11, 2007
nevermind,but I really think you would enjoy WU more if you stopped talking about the tunnels constantly.It's not like anyone on here could do anything about building the tunnels even if they agreed with you.Send letters to NOAA or the CPC.
Member Since: December 9, 2006 Posts: 125 Comments: 11346

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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.