Steve Connor: A clear picture of accelerated warming that shows no sign of levelling off

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The Independent Online

The latest and most comprehensive analysis of the global climate shows that every indicator of climate change points to the fact that global warming is for real and that it has not "stopped" as some sceptics have suggested.

It has also found that something like 93 per cent of the extra heat has been taken up by the oceans, so it is hardly surprising that this additional warming may be having a detrimental impact on the microscopic plant life that forms the base of the marine food chain.

The 2009 State of the Climate report by the US National Oceanic and Atmospheric Administration (NOAA) brings together for the first time nearly 50 independent records of global trends covering 10 aspects of climate change, from temperature rises over land and sea and increases in ocean heat content and sea level to decreases in snow cover, the size of glaciers and the area covered by Arctic sea ice.

When compiled in one report, the clear and unambiguous picture that emerges is one of a world experiencing a consistent warming which appears to have accelerated since the middle of the 20th century with no signs of it levelling off as a result of the much-trumpeted "global cooling" promulgated by some sceptics.

The amount of heat now entering the oceans as a result of global warming is estimated to be equivalent to the energy of 500 electric lightbulbs, each of 100 watts, for every one of the 6.7 billion people living in the world today. "The point is, it's a heck of a lot of heat," said Peter Stott, one of the Met Office's scientists who contributed to the NOAA report.

"When we follow decade-to-decade trends using different data sets and independent analyses from around the world, we see clear and unmistakable signs of a warming world," he added.

Much of the heat is accumulating in the surface layers of the oceans, where the phytoplankton live, but some of it is now being detected in the lower depths, some 6,000 feet below the surface. One direct effect of this additional heat is that sea levels are rising due to the thermal expansion of water – one of the 10 indicators of climate change highlighted in the report.

Global average temperatures have increased by 0.56C over the past 50 years and, although apparently small, this rise has already altered the planet, according to Jane Lubchenco, a marine scientist and head of the NOAA.