The average global temperature for 2018 is set to be the fourth highest on record, the United Nations' World Meteorological Organization (WMO) said Thursday.



The 20 warmest years on record occurred in the last 22 years, while the "top four" took place in the last four years, the WMO added.



The WMO's Provisional Statement on the State of the Climate in 2018 also found that "tell-tale signs of climate change" like sea-level rise, sea ice and glacier melt, and ocean heat and acidification were continuing. Extreme weather had "left a trail of devastation on all continents," the WMO said.



The WMO's report showed that for the first 10 months of the year, global average temperature was almost 1 degree Celsius above the pre-industrial baseline, which it defines as being between 1850 and 1900. These data were based on five global temperature data sets that were independently maintained, the WMO added.



"We are not on track to meet climate change targets and rein in temperature increases," Petteri Taalas, the WMO's secretary-general, said in a statement Thursday.



"Greenhouse gas concentrations are once again at record levels and if the current trend continues we may see temperature increases (of) 3-5°C by the end of the century," he added. "If we exploit all known fossil fuel resources, the temperature rise will be considerably higher."

The WMO's report comes just days before world leaders meet for a crucial climate change conference in Katowice, Poland, known as COP24.



In a strongly-worded statement, the WMO's Deputy Secretary General, Elena Manaenkova, sought to highlight just how important the issue of a warming planet was.



"Every fraction of a degree of warming makes a difference to human health and access to food and fresh water, to the extinction of animals and plants, to the survival of coral reefs and marine life," she said.



"It makes a difference to economic productivity, food security, and to the resilience of our infrastructure and cities," she added. "It makes a difference to the speed of glacier melt and water supplies, and the future of low-lying islands and coastal communities. Every extra bit matters."

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