Wednesday, January 16, 2008

The "sheet hits the fan"

There have been several interesting developments over the last few weeks in the evolving (intelligently designing?) climate change story. As we reported on last month (reposted here), NOAA's National Climatic Data Center's preliminary report on the climate of 2007 indicated that last year was the fifth warmest on record worldwide. This was confirmed in the final report, issued yesterday.

Meanwhile, an article in Saturday's carbon-based WaPo, "Last Year Among Hottest On Record, Say Scientists", reported that NASA's Goddard Institute for Space Studies had found that the year was the second warmest on record.

Gavin Schmidt, one of the climatologists involved in the NASA study, appeared on this morning's Diane Rehm show on WAMU, 88.5 FM, along with several other guests to discuss the policy implications of the science. Schmidt is also one of the primary contributors to the RealClimate blog. Streaming audio of the program is available on the show's web site, and a podcast can be downloaded from iTunes.

Locally, the warm last third of December pushed the yearly average to within about one hundredth of a degree of undisputed ownership of 12th place in the rankings of warmest years.

On Monday, the WaPo front page featured an article, "Escalating Ice Loss Found in Antarctica". This was based on the report, "Recent Antarctic ice mass loss from radar interferometry and regional climate modelling", published online on Sunday by the scientific journal Nature Geoscience. The gist of the latest finding is that the West Antarctic ice sheet is shrinking at a faster than expected rate.

The original paper itself is available only by subscription, but a summary was published online by the related Nature News. Former government energy official Joe Romm comments on the subject in a post, "The Antarctic ice sheet hits the fan", on his Climate Progress blog.

Winter 2.0, The Sequel

Clear commute; wintry mix likely tomorrow

Precisely one year ago today,'s PM Update noted that the pattern had shifted exactly halfway through meteorological winter from a mild regime to a more wintry one, and a similar shift is happening this year. With yesterday's return to within one degree of the daily average temperature, the stage is set for a wintry mix of precipitation as a developing low pressure area emerges from the Gulf of Mexico and moves northeastward up the Atlantic coast.

The key to the forecast is the fact that there is cold air in place and a good moisture supply, but the mechanism to hold the cold is not there, and as the wind moves to a southeasterly direction, much of the precipitation is likely to change to rain.

Tonight: After this afternoon's temperatures mainly in the low 40s, some high clouds will be accompanied by upper 30s to near 40 this evening. Clouds will increase overnight as lows reach 30-32 in the city and the mid to upper 20s in the 'burbosphere.

Tomorrow: Unless you sleep as late as we do here at CommuteCast Central, your morning commute should be cold, but dry. Precipitation in the form of snow or sleet will develop from southwest to northeast across the region from late morning into early afternoon. Temperatures in the low 30s will drop a couple of degrees to freezing or below when precipitation begins, but will gradually warm a little toward evening, and precipitation in the immediate metro area will change to freezing rain or plain rain. An inch or two of snow is possible before the change, especially north and west of the Beltway. As usual in this type of situation, the changeover will be most rapid east of I-95.

See Dan's post for the rest of the forecast, including a look ahead to the weekend.

Tuesday, January 15, 2008

Breezy, Cold After Snow Show

Mostly sunny tomorrow

Some leftover spin in the atmosphere in the wake of the snowstorm departing to the northeast from the Canadian Maritimes brought some vigorous, if brief, snow flurries to the Washington metro area around noon today. (We'll try to have more on the spin factor in a future News&Notes; for a preview, check out the infrared satellite loop at Unisys.)

Temperatures at mid afternoon have been in the mid to upper 30s, with a wind from the west gusting as high as 25 mph.

Tonight: Winds will be gusty through this evening but diminish later on tonight. Commute-time temperatures in the low 30s will drop to lows in the upper 20s downtown to the low and mid 20s in the 'burbosphere under partly cloudy skies.

Tomorrow: Highs will be 40-45 under mostly sunny skies.

See Matt's post for the rest of the forecast, including a look ahead to the weekend, and the Snow Lover's Crystal Ball for the latest thinking on Thursday's snow potential, or lack thereof.

Seasonal Outlook

Latest seasonal forecast: Click here.

Latest 3-month temperature outlook from Climate Prediction Center/NWS/NOAA.