2010, 2005 tied as warmest years on record

In a clear indication of global warming manifesting in extreme weather conditions – recall the heat wave in Moscow and the floods in Pakistan and Australia – 2010 tied with 2005 as the warmest year on record for global surface temperature, US government scientists said in a report on Wednesday.

The Earth in 2010 experienced temperatures higher than the 20th century average for the 34th year in a row, the National Oceanic and Atmospheric Administration (NOAA)said.

Overall, 2010 and 2005 were 0.62 degrees Celsius above the 20th century average when taking a combination of land and water surface temperatures across the world, it said. Those two years were also the highest in temperature since record-keeping began in 1880.

"If the warming trend continues, as is expected, if greenhouse gases continue to increase, the 2010 record won't stand for long," said James Hansen, director of Goddard Institute for Space Studies.

Last year was also the wettest on record, NOAA said, citing Global Historical Climatology Network which made the calculation based on global average precipitation, even though regional precipitation patterns varied widely.
When it came to hurricanes and storms, the Pacific Ocean saw the fewest number of hurricanes and named storms, three and seven respectively, since the 1960s.

But the Atlantic Ocean told a different story, with 12 hurricanes and 19 named storms, which include tropical storms and depressions, marking the second highest number of hurricanes on record and third highest for storms.

The analysis also tracked weather changes that contributed to massive floods in Pakistan and a heat wave in Russia, saying an "unusually strong jet stream" from June to August was to blame.

"The jet stream remained locked in place for weeks, bringing an unprecedented two-month heat wave to Russia and contributing to devastating floods in Pakistan at the end of July," it said.

Record snowfalls at the start of the year in the northeast including Washington and Philadelphia were part of a winter pattern driven by El Nino and the Arctic Oscillation, NOAA said.

Arctic sea ice acts like a blanket, insulating the atmosphere from the ocean's heat. Take away that blanket, and the heat can escape into the atmosphere, increasing local surface temperatures.

The loss of sea ice may also be driving Arctic air into the middle latitudes. Winter weather patterns are notoriously chaotic, and the GISS analysis finds seven of the last 10 European winters warmer than the average from 1951 to 1980. "One possibility is that the heat source due to open water in Hudson Bay affected Arctic wind patterns, with a seesaw pattern that has Arctic air downstream pouring into Europe," Hansen said.