Last three years hottest on record

The study confirmed a provisional finding that 2016 was the warmest year in records dating back to the 19th century, with 2017 and 2015 tied for second place in a warming trend. WMO blames the warming on man-made emissions of greenhouse gases. Atlantic hurricanes and monsoon floods in India contributed to make 2017 the most costly year on record for severe weather and climate events.

"The start of 2018 has continued where 2017 left off - with extreme weather claiming lives and destroying livelihoods," WMO Secretary-General Petteri Taalas wrote in the report.

Talaas said unusually high temperatures in the Arctic in 2018 contrasted with bitter winter storms in Europe and North America.

Also so far in 2018, "Australia and Argentina suffered extreme heat waves, whilst drought continued in Kenya and Somalia, and the South African city of Cape Town struggled with acute water shortages," he said.