Posted at 8:20 AM on December 16, 2009
by Paul Huttner
Global temperatures so far in 2009 show a cool trend in the Upper Midwest, while most of the globe runs above average. (Source: NOAA's Climatic Data Center)
The numbers are in for November from NOAA's Climatic Data Center.
Global temperatures for November (combined land and ocean) were 1.08 degrees Fahrenheit above the 20th century average. That makes November the 4th warmest on record in the past 130 years.
It appears even more likely now that 2009 will go down as the 5th warmest year on record since 1880. Global average temperatures are expected to close the year at about 1.01 degrees Fahrenheit above the 20th century average.
If 2009 finishes as the 5th warmest year on record as expected, that means 9 of the past 10 years are all in the top 10 warmest years on record globally. In fact, the past 9 years in a row are among the top 10 warmest years on record since 1880.
Global Top 10
Warm Years (Jan-Dec) Anomaly °C Anomaly °F
2005 0.61 1.10
1998 0.60 1.08
2003 0.58 1.04
2002 0.57 1.03
2009* 0.56* 1.01*
2006 0.56 1.01
2007 0.55 0.99
2004 0.54 0.97
2001 0.52 0.94
2008 0.48 0.86
*Value estimated using ten (January-October) months of data. This table will be updated by mid-January. (Source: NOAA's NCDC)
The decade of the 2000's will go down as the warmest decade since modern records began in 1880.
The implications of another "top 10 warmest" year are considerable. 2009 (+1.01F) will come in warmer than 2008 (+0.86F) and 2007 (+0.99F). Many have tried to suggest that the earth is in a cooling phase. While you cannot look at one year of data as a climate trend, a warmer 2009 certainly does not support claims of a multi-year global cooling trend.
It is still remarkable that 2009 will go down as yet another top 10 warmest year in the global surface record. While climate systems do not behave randomly, it is still amazing to me that we have not had one cooler than average year globally since 1984.
Even with climate, you might expect enough random variability to produce at least one cooler than average year in the past 25 years. We have been through several El Nino and La Nina phases since 1984. This strongly suggests that some much stronger climate forcing is at work.
It will be interesting to see what 2010 brings.
Posted at 4:58 PM on December 16, 2009
by Paul Huttner
Weather Underground surface temperatures plot at 2pm CST today shows surge of warm air in the 60s in Kansas.
What a difference a few hundred snow covered miles can make.
As arctic air reluctantly begins to release its icy grip from Minnesota, warmer air is slowly filtering in from the south. Look for a moderating trend by tomorrow afternoon. We should warm into at least the mid 20s.
This will be one of those nights when temperatures buck the usual overnight trend of falling until 8 am or so. There should be enough warm air spilling north, what meteorologists call "warm advection" to keep temperatures nearly steady overnight.
We can dream of that warm air coming north into Minnesota, but the reality is most of it won't get here. The main reason is our dense snow cover to the south. As the warmer air slides north, contact with the icy snow cover will modify the air mass chilling it down.
It is interesting to watch surface maps, and how semi-stationary "warm fronts' deveop on the southern edge of snow cover. The warm air slides north, but the "warm fronts" don't really move north at all. Surface winds even shift to the southeast on the north side of these fronts. The air mass essentially forms a stationary boundary at the edge of the snow pack.
Enjoy the milder trend the next few days. The forecast models are still wavering between near average to arctic air masses next week.