The latest temperature statistics are a sign of man-made global warming, the Met Office says This year is heading to be the hottest or second hottest on record, according to the Met Office.
It says the past 12 months are the warmest recorded by Nasa, and are second in the UK data set, HadCRUT3.
The Met Office says it is very confident that man-made global warming is forcing up temperatures.
Until now, the hottest year on record has been 1998, when temperatures were pushed up by a strong El Nino - a warming event in the Pacific.
This year saw a weaker El Nino, and that fizzled out to be replaced by a La Nina cooling event.
So scientists might have expected this year's temperatures to be substantially lower than 1998 - but they are not. Within the bounds of statistical error, the two years are likely to be the same.
"It's a sign that we've got man-made global warming," said Dr Vicky Pope, head of climate science advice at the Met Office.
The last decade was the hottest on record, and Dr Pope warns it will turn out to have been even hotter by about 0.03C when corrections are made to data taken from buoys at sea.
Dr Vicky Pope Met Office“A lot of the heat could be distributed to the deep oceans and we don't know what's going on there”
The buoys take temperature measurements a metre below the surface, where it is slightly cooler than on the surface itself. Measurements were previously taken mainly by ships.
Climate sceptics say that until now, warming has plateaued over the last decade. The Met Office agrees that the rate of warming has slowed - but it maintains that is due to natural variability, not because man-made warming has stopped.
They think factors in the slower warming may have been - a natural downturn in solar radiation; a small reduction in water vapour in the stratosphere; a possible increase in aerosol emissions from Asia; and the fact that strong warming in the Arctic is poorly represented in the way data is collected.
Dr Pope says the slowdown in temperature rise is consistent with projections from climate models. She also says she expects warming to increase in the next few years.
"The long-term warming trend is 0.16C," she says. "In the last 10 years the rate decreased to between 0.05 and 0.13.
"There are a number of things that are affecting short-term temperatures. A lot of the heat could be distributed to the deep oceans and we don't know what's going on there."
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Source: http://www.bbc.co.uk/go/rss/int/news/-/news/uk-11841368
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