2010: Hottest Year on Record?

Welcome to 2010, the soon-to-be hottest year on record.

This week the US National Oceanic and Atomspheric Administration (NOAA) released its preliminary global temperatures for April. Verdict: hot.

In fact, this April was the hottest on record:

• April global land and ocean surface temperature: warmest on record.
• April global ocean surface temperature: warmest on record.
• January to April global land and ocean surface temperature: warmest on record.
• January to April global ocean surface temperature: second warmest on record.

This follows on the heels of the hottest March on record, and comes while the sun is taking a virtual nap, contributing nothing to the warming trend.

This April beat April 1998, currently the second hottest year on record behind 2005. The comparison is significant: 1998 benefitted from a much stronger El Niño and a solar maximum. This year’s heat wave comes despite this year’s relatively weak El Niño and one of the most extreme solar minima on record.

Hopefully, the warm 2010 ocean temperatures will put the final nail in the coffin of the “urban heat island” skeptics. Unless they want to claim that the fabled city of Atlantis is causing all this ocean warming.

So what happens when the sun finally wakes up? You do the math. The only encouraging news for our immediate global warming picture is that scientists expect the next solar maximum to be fairly small.

Here are more details from NOAA’s monthly report:

• Combined April global land and ocean average surface temperature: warmest on record at 58.1°F (14.5°C), 1.37°F (0.76°C) above the 20th century average. (Not that this is a trend or anything, but that’s the 34th consecutive April at above average temperatures.)
• Combined global land and ocean average surface temperature: warmest on record for January-April at 56.0°F (13.3°C), 1.24°F (0.69°C) above the 20th century average.
• April global ocean surface temperature: warmest on record at 61.93°F (16.57°C), 1.03°F (0.57°C) above the 20th century average.
• April global land surface temperature: third warmest on record at 2.32°F (1.29°C) above the 20th century average of 46.5 °F (8.1°C).
• El Niño weakened in April, with Pacific Ocean sea-surface temperature anomalies decreasing. The weakening contributed significantly to the warmth observed in the tropical belt and the warmth of the overall ocean temperature for April. According to NOAA’s Climate Prediction Center, El Niño is expected to continue through June.
• April North American snow cover extent: smallest on record. It also was the largest difference below the long-term average on record for any month.

NOAA reported that ocean hot spots were primarily in the equatorial areas, especially in the Atlantic. Warmer-than-normal land surface conditions dominated the globe, with Canada, Alaska, the eastern United States, Australia, South Asia, northern Africa and northern Russia especially toasty. Who missed out? Mongolia, Argentina, far eastern Russia, the western United States and most of China were cooler than usual.

Any contrary or cooling observations? Sort of:

• Antarctic sea ice was only just below average.
• Arctic sea ice, while still below normal for the 11th consecutive April, was the largest sea ice extent since April 2001.

Well, that’s encouraging. Except that climate scientists have predicted that Antarctic sea ice would be less effected initially by global warming, possibly even increasing due to a variety of factors including increased snowfall, ozone depletion and ocean currents.

Meanwhile in the Arctic, sea ice reached maximum extent on March 31, a good month later than normal. Remember those cooler than usual temperatures in far eastern Russia? They contributed to sea ice growth in southernmost Bering Sea, Barents Sea, and Sea of Okhotsk.

Elsewhere in the Arctic? Sea ice below average, temperatures above average.

Changing wind patterns are pushing older, thicker ice south along Greenland’s east coast, where it will likely melt during the summer.

Forecast for summer ice: hasta la vista, baby.