2007 is hardly a memory in our minds but already British forecasters are predicting that 2008 will be another member of the Top 10 hottest years since 1850 club. Thus, they say, there is no indication that global warming is on the wane; much is the pity!
The Met Office and experts at the University of East Anglia announced on Thursday that the global average temperatures for 2008 would be 0.37 of a degree Celsius above the long-term 1961-1990 average of 14 degrees and be the coolest since 2000.
The study behind the predictions took in to account not only the annual Pacific Ocean La Nina event which is expected to be especially strong, but also natural changes in the ocean currents, solar variations and atmospheric concentrations of greenhouse gasses.
“The fact that 2008 is forecast to be cooler than any of the last seven years does not mean that global warming has gone away,” said Phil Jones, director of climate research at UEA.
“What matters is the underlying rate of warming – the period 2001-2007 with an average of 0.44 degree C above the 1961-90 average was 0.21 degree C warmer than corresponding values for the period 1991-2000.”
Particularly influential are the effects of El Nino and La Nina, with the ocean-atmosphere phenomenon having a strong impact upon global temperatures. La Nina reduces the sea surface temperature by around 0.5 degrees Celsius while El Nino has the opposite effect.
“Phenomena such as El Nino and La Nina have a significant influence on global surface temperature and the current strong La Nina will act to limit temperatures in 2008,” said Chris Folland from the Met Office Hadley Centre.
“However mean temperature is still expected to be significantly warmer than in 2000, when a similar strength La Nina pegged temperatures to 0.24 degree C above the 1961-90 average. Sharply renewed warming is likely once La Nina declines,” he added.
The current La Nina is the strongest since the 1999-2000 one, but this time the Indian Ocean Dipole has occurred simultaneously causing the abnormal drought conditions in Australia, which should be much wetter during such a strong La Nina event.
Reuters via ENN – 2008 to be in top 10 warmest years say forecasters
Photo Courtesy of m o d e via Flickr