This year looks set to be the second warmest on record. Unless there is a dramatic cooling in November and December, 1991 will take its place behind 1990, but ahead of 1988 and 1987. This will mean that the four warmest years of the past century have all been in the past five years.
According to David Parker, of the Meteorological Office's Hadley Centre for climate research, 'the first half of this year was as warm as the same period in 1990, but the second half has cooled slightly, perhaps because of the shading effect of the volcanic eruption of Mount Pinatubo in the Philippines.' Particles blown into the stratosphere by large volcanic eruptions spread round the Earth, shading the surface from the Sun's radiation.
The data compiled by Parker and Phil Jones, of the Climatic Research Unit of the University of East Anglia, include land and sea temperatures. They ...
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