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WMO: Five hottest years on record have occurred since 2011

By Matt McGrath
Environment correspondent

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  • Climate change
image copyrightWMO
image captionThe areas of the world which have been warmer than the long term average between 2011-2015

New data released by the World Meteorological Organisation (WMO) shows that the five years from 2011 to 2015 were the warmest on record.

The report, published at global climate talks in Morocco, strongly links human activities to rising temperatures.

It says that some studies found the the burning of fossil fuels had increased the probability of extreme heat by 10 times or more.

The authors say that 2016 will likely break the record for warmest year.

African exception

In their report on the global climate 2011-2015, the WMO says that the world's temperature was 0.57C above the long term average, which they define as being between 1961 and 1990. The five year period was the warmest for all continents except Africa.

Throughout these years, temperatures over most of Europe were more than one degree Celsius above the long term trend.

This was also the case in the Asian part of the Russian Federation, over much of the Sahara and Arabian regions, parts of South Africa, southwest US and the interior of Brazil. The mercury even reached three degrees above the average on the Arctic coast of Russia.

image copyrightGetty Images
image captionThe report suggests the burning of fossil fuels increased the probability of extreme heat events by a factor of 10

"The Paris Agreement aims at limiting the global temperature increase to well below 2 degrees Celsius and pursuing efforts towards 1.5 degrees Celsius above pre-industrial levels," said WMO Secretary General Petteri Taalas.

"This report confirms that the average temperature in 2015 had already reached the 1 degree C mark. We just had the hottest five-year period on record, with 2015 claiming the title of hottest individual year. Even that record is likely to be beaten in 2016."

The rise in temperatures is linked directly to the increase in greenhouse gas levels in the atmosphere. In 2015 the WMO says the annual mean concentrations of CO2 were at the symbolically important level of 400 parts per million (ppm), having grown by between 1.9ppm and 2.99ppm between 2011 and 2015.

The new report highlighted the human fingerprint in these emissions and the link to extreme weather events by looking at academic literature in the Bulletin of the American Meteorological Society (BAMS).

"Of 79 such studies published by BAMS between 2011 and 2014, more than half found that anthropogenic climate change contributed to the extreme event under consideration," the new report says.

image copyrightGetty Images
image captionClimate change made the likelihood of extreme rainfall in the UK about 40% more likely in 2015

The review says that the most consistent influence of the use of fossil fuels on the climate has been on the probability of extreme heat. Some studies showed that the probability has increased by ten times or more. Among the heat events that the report highlights include the record high seasonal and annual temperatures in the US in 2012 and in Australia in 2013.

Other significant events that the WMO believes are linked to warmer temperatures include the East African drought in 201-2011 which caused an estimated 258,000 excess deaths. They also point to heat waves in India and Pakistan in 2015 that claimed more than 4,100 lives.

"The effects of climate change have been consistently visible on the global scale since the 1980s: rising global temperature, both over land and in the ocean; sea-level rise; and the widespread melting of ice," said the WMO's Petteri Taalas.

"It has increased the risks of extreme events such as heatwaves, drought, record rainfall and damaging floods," he said.

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