By Roger Harrabin
16 November 2015
(BBC News) – Human societies will soon start to experience adverse effects from manmade climate change, a prominent economist has warned.
Prof Richard Tol predicts the downsides of warming will outweigh the advantages with a global warming of 1.1C - which has nearly been reached already.
Prof Tol is regarded by many campaigners as a climate "sceptic".
He has previously highlighted the positive effects of CO2 in fertilising crops and forests.
His work is widely cited by climate contrarians.
"Most people would argue that slight warming is probably beneficial for human welfare on net, if you measure it in dollars, but more pronounced warming is probably a net negative," Prof Tol told the BBC Radio 4 series Changing Climate.
Asked whether societies were at the point where the benefits start to be outweighed by consequences, he replied: "Yes. In academic circles, this is actually an uncontroversial finding."
But it is controversial for climate contrarians, who often cite Professor Tol's work to suggest that we shouldn't worry about warming. […]
Richard Tol from Sussex University believes discussion over the impacts of a 2C temperature rise is largely irrelevant as the world is likely to warm by between 3-5C, because politicians at the forthcoming Paris climate summit won't be willing or able to make the scale of cuts needed to keep temperature rises under 2C.
He says a rise of 4C would be undesirable but manageable for Europe and all nations rich enough to cope with the costs of adaptation. The best way of combating climate change, he told BBC News, was to maximise economic growth.
Tim Lenton, professor of Earth systems science from Exeter University, told us this was a highly optimistic prognosis under a 4C rise.
"The land surface of central Europe would be quite a lot more than 4C warmer on average, changing potentially the pattern of seasonality over Europe.
"We would have lost the summer Arctic sea-ice, [and] would have sea-ice cover radically thinned in winters.
"We're seeing already that appears to have some connection to changes in the pattern of weather and weather extremes and the changes in the distribution of rivers and river flows.
"We might then speculate about how intense Mediterranean drying might drive … movements of people. It would be a very different Europe." [more]