A British journalist is questioning the method used to by scientists to calculate the earth's climate change, calling it "one of the greatest scientific scandals of all time."Christopher Booker writes for Britain's The Telegraph that climate data from stations in South America have been adjusted since the 1950s to give the impression that the earth's temperature is rising more than the original data showed.Booker cites Paul Homewood's Not a Lot of People Know That blog where Homewood compares raw data with adjusted temperatures to show the graph trend was reversed from a cooling trend to a warming one.Homewood checked the data on three weather stations in Paraguay and found that all three had their initial raw readings adjusted to show lower temperatures in the 1950s and higher temperatures today.Following reporting by Booker two weeks ago, Homewood checked more stations in South America and found the same thing had occurred at them.Scientists use these records to estimate temperatures in locations that don't have reporting stations, and the data is used to project changes in overall global climate.Homewood is now looking at stations in the Arctic between Canada and Siberia, Booker reports."Again, in nearly every case, the same one-way adjustments have been made, to show warming up to 1 degree C or more higher than was indicated by the data that was actually recorded," Booker writes.Traust Jonsson, a longtime climate researcher in Iceland was surprised to see the revised data "disappears" Iceland’s "sea ice years" around 1970, when a period of extreme cooling almost wiped out Iceland's economy.Homewood reportedly became interested in the subject because of the arguments from climate scientists that rising global temperatures is causing the melting sea ice in the Arctic.In reality, Homewood says, the melting is caused by cyclical shifts in Atlantic sea currents that bring warmer water to the area. Arctic water temperatures last peaked 75 years ago, when sea ice melted back even further than today, he said.