Ex Met Office chief in global warming appeal; SIR JOHN REACTS TO LATEST UN REPORT ON CLIMATE CHANGE.
ONE of the world's leading climate scientists says the latest United Nations (UN) report on global warming leaves "almost no doubt at all" that humans are to blame for heating up the planet.
Former head of the Met Office Sir John Houghton said the report by the Intergovernmental Panel on Climate Change (IPCC) shows that even if we "turned off the carbon dioxide tap" the planet would continue heating up for another half a century.
Sir John, who is a former Nobel Prize winning chair of the Intergovernmental Panel, said the report shows the risks of failing to act over global warming are now simply too great to gamble on.
The panel's report says it's extremely likely, or 95% to 100% certain, human influence has been the dominant cause of global warming since the mid-20th century.
The IPCC publishes its work every six years and last time round in 2007 it said it was 90% certain humans were at fault over global warming.
In the report Climate Change 2013: The Physical Science Basis, the scientists conclude that each of the last three decades has been successively warmer at the earth's surface than any preceding decade since 1850.
Sir John, 81, who chaired the IPCC between 1988 and 2002, said: "We're going to get a lot worse in the future whatever we do."
The retired scientist, from Aberdyfi, in Gwynedd, who was among a group of researchers to accept the Nobel Prize in 2007 on behalf of the IPCC - an honour they shared with former US vice president Al Gore - added: "If we don't turn it off now, but wait 10 or 20 years then we'll have even more to try to adjust to."
The IPCC report concluded the "atmosphere and ocean have warmed, the amount of snow and ice has diminished, the global mean sea level has risen and the concentrations of greenhouse gases have increased".
It suggested global surface temperature change over the next nine decades or so is likely to exceed 1.5degC compared to 1850 to 1900 in "all but the lowest scenario considered".
In worst case scenarios it is likely to exceed 2degC, causing more heatwaves over long periods, greater levels of rainfall in wet regions and dry areas to become still more arid.
Limiting climate change will require substantial reductions of greenhouse gas emissions, concluded the report.
But others maintain a pause in warming since 1998 supports their claims climate change has been exaggerated.
Dutch science writer Marcel Crok has expressed doubts about the scale of the sensitivity of the climate to carbon emissions.
He told the BBC: "The sceptics now have a feeling of being on the winning side of the debate thanks to the pause.
"You are now starting to see a normalisation of climate science.
Suddenly mainstream researchers, who all agree that greenhouse gases play a huge role, start to disagree about the cause of the pause."
But the Climate Change Commission for Wales, which includes scientists, business leaders and politicians, said the IPCC's report shows it's time for urgent action.
Chair of the Commission Peter Davies, said: "The evidence that climate change is happening and that a significant cause is human activity - the burning of fossil fuels - is unequivocal."
In 2011 total net greenhouse gas emissions in Wales were 43.8 mega tonnes (Mt), a drop of about 5.5% or 2.5Mt on 2010.
In 2011 emissions in Wales were 20.6% lower than in 1990 or 1995. The is better than the 12.5% reduction on 1990 levels demanded by the Kyoto agreement.
However, Wales has reduced its emissions by 8.5 percentage points less than the UK average. Scotland and England have had larger percentage reductions in emissions than Wales, while Northern Ireland's falls were lower.
Welsh Government Natural Resources Minister Alun Davies pointed to programmes like Nest and Arbed, which will invest PS13m over three years in trying to cut fuel consumption among vulnerable groups.
He added: "The risks we face as a result of climate change include the warming of the world, loss of ice, an increase in global average sea level and an increased risks of extreme weather over the coming decades."
| Former head of the Met Office Sir John Houghton
A flooded street at Quezon city, northeast of Manila, following heavy rains brought about by Typhoon Usagi