Nigel Lawson and others are suggesting that temperatures have ‘stabilised’ since the late nineties. 1998 saw the highest global average temperature and only 2005 has closely matched it. Since no year since 1998 has exceeded the record, some commentators are saying the global warming has stopped. The implication, sometimes stated, sometimes not, is that the increasing rate of growth of CO2 concentration is having no effect on temperature.

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The sceptics have also written extensively about what they saw to be an extremely cold northern-hemisphere winter. The Sunday Telegraph commentator Christopher Booker called it ‘the winter from hell’. To those unconvinced by the man-made climate change hypothesis, this is further evidence that climatologists don’t understand how CO2 affects temperature.

Both UK and US sceptics are too influenced by climatic conditions in America. Although parts of the United States did have an unusually cold winter, global temperatures have been high.

Here is the summary from the US National Climatic Data Centre of northern winter averages:

The combined global land and ocean surface temperature was the 16th warmest on record for the December 2007-February 2008 period (0.58°F/0.32°C above the 20th century mean of 53.8°F/12.1°C). The presence of a moderate-to-strong La Niña contributed to a boreal winter and February temperature that were the coolest since the La Niña episode of 2000-2001.

Although the period was the ‘16th warmest’, it was still the coldest for several years. But March was very much warmer. Here is what the NCDC says about this month:

The global surface (land and ocean surface) temperature was the 2nd warmest on record for March in the 129-year record, 1.28° F (0.71° C) above the 20th century mean of 54.9° F (12.7° C). The warmest March on record (+1.33° F/0.74° C) occurred in 2002.
The global land surface temperature was the warmest on record for March, 3.3° F (1.8° C) above the 20th century mean of 40.8° F (5.0° C). Temperatures more than 8° F above average covered much of the Asian continent. Two months after the greatest January snow cover extent on record on the Eurasian continent, the unusually warm temperatures led to rapid snow melt, and March snow cover extent on the Eurasian continent was the lowest on record.

Without the continuing (but weakening) La Niña event, the global average sea and land temperature would almost certainly have been the warmest on record in March. 1998 was an extreme anomaly, with temperatures in the US over 1 degree C higher than the previous year. This was driven by a strong El Niño and there is no reason to suppose that the next El Niño event will not produce an even higher temperature.

Climate change sceptics need to get out more. April snow in southern England or in New York does not mean climate change has stopped. Any talk of ‘stabilisation’ is premature.