Global warming was to blame for super storms that killed hundreds of people last year, and record levels of ice thaw in the Arctic, the United Nations has warned.
As national representatives meet in Bonn, Germany, for the latest round of climate change negotiations, the World Meteorological Organisation (WMO) issued its latest report on the damage attributed to global warming.
The annual summary, which will inform policymakers around the world, confirmed that 2012 was the ninth warmest year on record.
The global average temperature in 2012 was 0.45C warmer than the 1961 to 1990 long-term average of 14C.
Although this was a relatively small increase compared with previous years, leading to suggestions that global warming was "slowing down", it continues a steady upwards trend. Last year was the 27th consecutive year with an above-average global temperature.
The report also pointed out that Arctic ice was at a record low, rainfall increased causing floods around the world and a number of countries experienced drought.
Extreme weather events, such as Superstorm Sandy in the US and Typhoon Bopha in the Philippines, were linked to climate change and the damage and death toll could be exacerbated by rising sea levels.
Michel Jarraud, the secretary-general of the WMO, said the extreme events in 2012 were "a sign of things to come".
"Although the rate of warming varies from year to year ... the sustained warming of the lower atmosphere is a worrisome sign," he said.
Jarraud said the warming climate has made extreme weather events more likely.
"Natural climate variability has always resulted in such extremes, but the physical characteristics of extreme weather and climate events are being increasingly shaped by climate change.
"For example, because global sea levels are now about 20cm higher than they were in 1880, storms such as Hurricane Sandy are bringing more coastal flooding than they would have otherwise."