A man clears snow from the paths outside his house in Wilkieston in West Lothian

With millions of Britons battling through snow and ice to get to work today, scientists claim that the cold conditions should not be used as evidence against man-made climate change. Blizzards, ice and sub-zero temperatures that have gripped the UK for almost a month in a record deep freeze are not “robust” indicators of global weather patterns, they say. Their claims come despite the fact that the rest of the northern hemisphere, from America to Europe and Asia, is suffering some of the worst winters in living memory. Huge snowfalls are being witnessed from China and South Korea, across eastern, central and western Europe and to America where even Florida is struggling to record temperatures above freezing.

Last night critics of the global warming lobby said the public were no longer prepared to be conned into believing that man-made emissions were adding to the problem. Long-term forecaster and trends analyst Piers Corbyn, of WeatherAction, said: “Global warming is a failed science built on falsified data. It is a sham to say that man has caused it.” But Stephen Dorling, of the scandal-hit University of East Anglia’s school of environmental sciences, remained adamant that the weather should not be used as evidence against climate change. But he added: “It’s no surprise that people look out of their window and find it hard to rationalise what’s going on with the longer term trend.”

But he said it was wrong to focus on cold snaps or heat waves but look instead at longer-term trends. The Met Office’s Barry Gromett said December and January’s cold weather was “within the bounds of variability” in a global trend of rising temperatures in which 2009 is set to be the fifth warmest year on record. He added that while Siberia, the UK and parts of the US were very cold, other areas including Alaska, Canada and the Mediterranean were warmer than usual. But China faces its worst winter in 20 years, with temperatures down to -43C. Mr Gromett added: “Climate change is likely to give us milder winters, but there’s always opportunities within that to have colder years.