Unexpected ocean cooling result found to be an error; 2nd warmest October on record

Since the publication in 2006 of the paper, Recent cooling of the upper ocean, climate scientists have been scratching their heads, trying to figure out why the upper layer of the ocean had cooled from 2004-2006. Since the oceans absorb more than 80% of the heat from global warming, we should expect to see the oceans heating up if the globe is warming. Climate skeptics pointed to the result as evidence that the planet was not warming after all, although surface and satellite measurements showed that the year 2005 was the warmest or second warmest year on record for the surface of the globe.

Now, the explanation for this apparent cooling of the oceans has been resolved--key measurements made by submersible robot buoys and that indicated the ocean was cooling were found to be in error. The new, corrected data show that no cooling of the oceans occurred in 2004-2006, in agreement with what the climate models were predicting. People often malign the accuracy of climate models, but sometimes they are more trustworthy than the data! The full story of the global ocean cooling mistake is presented in an excellent NASA article that I highly recommend reading. It gives a great picture of how science moves forward to correct mistakes.


Figure 1. Ocean temperature change from 2004 to 2006 originally showed drops of over 1.5° C in the Atlantic Ocean (top). The apparent large drop in temperature was due to bad data from buoys, and it disappeared when errors in these data sets were corrected (bottom). The remaining large swings in temperature visible in these maps are due to shifting positions of ocean currents. (Maps by Robert Simmon, based on data from Josh Willis and John Lyman.)

Second warmest October on record for the globe
The planet continues to stay extremely warm this year, though no record warm months have been recorded in 2008. October 2008 came the closest--it was the 2nd warmest October for the the globe on record, according to statistics released yesterday by the National Climatic Data Center. These statistics have been corrected for a widely reported error that was discovered earlier this month. Over land areas, October 2008 was the warmest October on record. The period January through October was the 9th warmest such period on record. Records extend back 129 years, to 1880. Much of the unusual warmth occurred over Asia, Australia, and Eastern Europe (Figure 2). According to the Australian Bureau of Meteorology, October 2008 was an exceptionally dry month in central and southeastern Australia, ranking as the driest October on record for South Australia, second driest for Tasmania, and third driest for Victoria.


Figure 2. Departure of temperature from average for October 2008. Image credit: National Climatic Data Center.

For the contiguous U.S., October was pretty ordinary. It was the 44th coolest and 51st driest October since 1895. October was the 7th wettest on record for the West North Central U.S. and the 17th driest for the Northwest U.S.

October 2008 Northern Hemisphere sea ice extent was the third lowest on record for the month of October, 34% below the mean from 1979-2000, according to the National Snow and Ice Data Center. This is 9.5% below the 1979-2000 average. The record October low was set in 2007.

There is neither a La Niña nor El Niño at present, and neutral conditions now prevail in the tropical Eastern Pacific. There is no indication that this will change in coming months, and most of the computer climate models forecast a continuation of neutral conditions over the next three months.

Portlight making keynote presentation at charity funding conference
The Portlight.org charity is making the keynote presenation at a funding conference hosted by a coalition of state and federal agencies which work in the area of post-disaster relief involving people with disabilities. The presentation is Thursday morning, November 20, at 9:15 am EST. You can follow the proceedings via the portlight webcam at stormjunkie.com. The webcam will also be running most of the day today as Stormjunkie and Presslord drive up to Atlanta for the conference, and host a Q and A session from their hotel room tonight. At the conference Thursday morning, they plan to discuss the Hurricane Ike relief efforts made possible by the Weather Underground community. Thanks for everyone's support for making all this possible!

I'll have a new blog post Thursday.

Jeff Masters