From the Telegraph by Christopher Booker...
Considering that the measures recommended by the world's politicians to combat global warming will cost tens of trillions of dollars and involve very drastic changes to our way of life, it might be thought wise to check the reliability of the evidence on which they base their belief that our planet is actually getting hotter.
There are four internationally recognised sources of data on world temperatures, but the one most often cited by supporters of global warming is that run by James Hansen of Nasa's Goddard Institute for Space Studies (GISS).
Hansen has been for 20 years the world's leading scientific advocate of global warming (and Al Gore's closest ally). But in the past year a number of expert US scientists have been conducting a public investigation, through scientific blogs, which raises large question marks over the methods used to arrive at his figures.
First they noted the increasingly glaring discrepancy between the figures given by GISS, which show temperatures continuing to race upwards, and those given by the other three main data sources, which all show temperatures having fallen since 1998, dropping dramatically in the past year to levels around the average of the past 30 years.
Two sets of data, from satellites, go back to 1979: one produced by Dr Roy Spencer, formerly of Nasa, now at the University of Alabama, Huntsville, the other by Remote Sensing Systems. Their figures correspond closely with those produced by the Hadley Centre for Climate Studies of our own Met Office, based on global surface temperature readings.
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Nasa is out of line on global warming