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Climate scientists at NASA’s Goddard Institute for Space

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Studies or GISS just released a new analysis of global average

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temperatures showing that 2009 was tied as the second warmest

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year ever recorded. And looking just at the southern hemisphere

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2009 even broke the record as the warmest year ever

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ever in this half of the world. In fact 2009 was

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virtually tied with 5 other recent years in its position as second

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warmest on record, 1998, 2002

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2003, 2006, and 2007

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and was only a fraction of a percent cooler than the warmest year, 2005.

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Yet when looking at global temperatures over a longer timeframe

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these scientists found a persistent warming trend over the past

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three decades, with the average global temperature increasing by

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roughly a third of a degree Fahrenheit per decade. This past decade,

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from 2000 to 2009, was the warmest yet.

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And when looking back all the way to 1880, the year when precise

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temperature record keeping began, scientists observed about a one and a half

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degrees Fahrenheit rise in global temperatures.

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[QUOTE: Jim Hansen] “There are

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already beginning to be effects of 1 or 2 degrees warming and

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if we get 5 or 10 degree warming several decades

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down stream there will be huge effects.”  GISS scientists came

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came to these results after analyzing information from three sources

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data from more than a thousand weather stations around the globe, satellite

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observations of sea surface temperature, and measurements from Antarctic research

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stations. So what’s the cause of this long term warming trend?

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While there are several natural processes that can cause subtle climate warming

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or cooling, like variations in solar activity, fluctuations

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in ocean currents, and volcanic eruptions, climate scientists

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believe that rising levels of carbon dioxide and other greenhouse gasses

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are the dominant factor driving the rise.

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[QUOTE: Jim Hansen] “If we want to limit

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climate change and keep it under

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an additional one degree Celsius or 2 degrees Fahrenheit

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we would need to begin to decrease the CO2

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emissions gradually so that by the end of the

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century CO2 stopped increasing.” So while 2009’s