Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.
By: Dr. Jeff Masters , 2:05 AM GMT on January 21, 2009
The temperature statistics are in, and the year 2008 ranks as the ninth warmest year for the globe on record, making it the coolest year since 2000, according to an analysis compiled by NASA. NOAA's National Climatic Data Center rated 2008 the eighth warmest on record, and the British Climate Research Unit rated it tenth warmest. NASA noted that given the uncertainty in the measurements, a range of 7th to 10th warmest was reasonable. Global temperature records extend back to 1880. December 2008 was also the eighth warmest December for the globe on record.
The average global temperature the past five years (and the last ten years) is the highest on record. The top ten warmest years since 1880 have all occurred in the past twelve years. So, despite the impressive cold blast in the Eastern U.S. this winter, the global climate is warming. The relatively cool temperatures of 2008 probably represent a normal year-to-year fluctuation in the weather. Cool weather is to be expected globally during a strong La Niña event in the Eastern Pacific Ocean, which was present during the first part of 2008 (see the cool blue colors over the Equatorial Pacific in Figure 1). It is no surprise that the last year it was cooler, 2000, was also the last time we had a La Niña event. With La Niña conditions beginning to develop again this year, I'd be surprised if 2009 turns out to be a record warm year. Dr. James Hansen of NASA is predicting a new global record temperature either this year or in 2010, though.
Figure 1. Global temperature anomalies in 2008 compared to the 1950-1980 baseline period. Below-average temperatures are shown in blue, average temperatures are white, and above-average temperatures are red. (Gray indicates no data.) Most of the world was either near normal or warmer than normal. Eastern Europe, Russia, the Arctic, and the Antarctic Peninsula were exceptionally warm (1.5 to 3.5 degrees Celsius above average). The temperature in the United States in 2008 was not much different than the 1951-1980 mean, which makes 2008 cooler than all of the previous years this decade. Large areas of the central and eastern Pacific Ocean were cooler than the long-term average, linked to a La Niña episode that began in 2007. The graph shows the long-term trend in surface temperatures since 1880. The annual average temperatures are shown in light orange, and the jaggedness of the line indicates how much the average global surface temperature varies from year to year. Because climate is so variable from year to year, it can be easier to spot long-term trends through multi-year averages. The dark red line shows the five-year running average, which is an average of five years of annual temperatures centered on a given year. Even this five-year average shows that climate has ups and downs, but the long-term increase in global average surface temperatures is obvious. The gray barbells indicate the range of uncertainty. Not surprisingly, the uncertainty is larger for older measurements than for more recent ones. Image credit: NASA.
A cool and snowy December in the U.S.
For the contiguous U.S., December was the 35th coolest December, ranking it in the coldest 30% of all Decembers observed since records began in 1895. December 2008 had near-average precipitation, ranking 43rd wettest. It was the 8th wettest December on record in the East North Central U.S., and 9th wettest for the Central U.S. Only the South experienced below average precipitation during the month. For the year 2008, temperatures in the U.S. were not much different than the 1951-1980 mean, which makes 2008 the coolest year since 1997. U.S. records set in December 2008 (courtesy of http://extremeweatherguide.com/updates.asp):
Spokane, WA: All-time 24-hour snowfall, 19.4", 12/17-12/18
Spokane, WA: All-time single storm snowfall: 23.3", 12/17-12/18
Sandpoint, ID: All-time 24-hour snowfall, 27.0"
Jackson, WY: All-time 24-hour snowfall, 27.0"
Fargo, ND: Snowiest month on record: 33.5"
Spokane, WA: Snowiest month on record: 61.5"
Green Bay, WI: Snowiest month on record: 45.6"
Madison, WI: Snowiest month on record: 40.4"
Wausau, WI: Snowiest month on record: 37.6"
Idaho: All-time 24-hour state snowfall record set at Dollar Hide, 46.5", 12/26-12/27 (not confirmed)
At the end of 2008, 20% of the contiguous United States was in moderate-to-exceptional drought. This is a decline from the 28% of the U.S. that was under similar drought conditions at the end of 2007. The average precipitation for the U.S. in 2008 was 30.48 inches, which is 1.34 inches above average. 2008 was the wettest year on record for New Hampshire and Missouri, second wettest for Massachusetts, and third wettest for Connecticut, Illinois, and Iowa. Also, 2008 was the fourth wettest year for Indiana, fifth wettest for Maine, Michigan, and Vermont, seventh wettest for New York, and eighth wettest for Kansas and Rhode Island.
Check out Ricky Rood's latest blog, called Cold in the East: A rant. There is a lot of misinformation circulating in the media right now about climate change, and Ricky and I will be doing our best to try to explain what is fact and what is crap in the coming weeks. I posted one such discussion last week, when I showed that the recent claims that sea ice is back to 1979 levels were a clever bit of cherry picking of the data that hides the critical summertime loss of Arctic sea ice. I'll have a new blog post on Friday.
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