An international panel of scientists will today launch a major inquiry to discover whether official world temperature records have exaggerated the extent of global warming.
The panel, convened by the Global Warming Policy Foundation (GWPF), the ‘climate sceptic’ think-tank led by the former Tory Chancellor Lord Lawson, will focus on thousands of ‘adjustments’ that have been made to temperature records kept at individual weather stations around the world.
Sceptics have argued that the effect of such adjustments – made when instruments are replaced or recalibrated, or heat-producing buildings are erected close to weather station sites – has skewed the records.
The panel will also examine ‘extrapolations’ – when the records include virtual figures from places where there is no actual measuring station, instead basing them on the figures of other stations in the same region. In some areas, such as the Arctic, these may be hundreds of miles away. Sceptics claim that the effect of the adjustments is usually to revise temperatures from decades ago downwards, and to increase recent readings, so that the warming trend of the past 150 years looks larger than it really is.