Year 2017 has also been marked by an unusually high number of extreme weather events, which scientists warn will continue unless greenhouse gases are reduced.
Weather forecasters are predicting 2017 will be one of the hottest on record, even without a boost from an El Niño.
It's also been marked by an unusually high number of extreme weather events, which scientists warn will continue unless greenhouse gases are reduced.
2017 has already had its fair share of extreme weather activities.
When Hurricanes Harvey and Irma hit, it was the first time the United States had two Category 4 or stronger hurricanes make landfall on the mainland in the same year.
An unprecedented level of rain - more than 1.5 metres - was recorded in Nederland, Texas, during Hurricane Harvey.
Meanwhile Chile has reported eight times the usual number of forest fires following drought in the country.
Many scientists believe these extreme weather events are the fingerprints of climate change at work.
Petteri Taalas, the Secretary-General of the World Meteorological Organisation, says 2017 is shaping up to be one of the warmest years on record.
"2017 is going to be among the three warmest years on record and it's much warmer than 2014, which was the previous year without the impact of an El Niño."
Temperatures this year will be slightly cooler than in 2015 and last year's record high.
But those years were both boosted by the warming effect of an El Niño.
Mr Taalas says the long-term warming trend has been driven by greenhouse gases from burning fossil fuels.
"Global warming is continuing, and that's very much because of the increase of greenhouse gases, and especially carbon dioxide."
Delegates from almost 200 countries have begun talks at a United Nations conference in Bonn, Germany, this week to work on details for implementing the 2015 Paris climate agreement and to try and step up action before 2020.
Many are united in their fight to tackle climate change, but conflicting messages are coming from the United States.
Trigg Talley, US Deputy Special Envoy for Climate Change, says the US will continue to take part in talks, despite President Donald Trump's threat to pull out of the pact.
"On June 1st, President Trump announced that the United States will withdraw from the Paris Agreement, unless he can identify terms for re-engagement that are more favourable to the American people. The administration's position remains unchanged."
Meanwhile just in the last week, a comprehensive review by 13 US federal agencies concluded that evidence of global warming is stronger than ever and that more than 90 per cent of it has been caused by humans.
In Australia, New South Wales and Queensland have been unusually warm this year.
Blair Trewin, a senior climatologist at the Bureau of Meterology, says Australia will have its third-warmest year on record.
"Australia is becoming hotter as the world is becoming hotter. Australia has warmed by about a degree over the last century which is fairly similar to the rate of warming worldwide as shown by the figures that have just come out."
Climate change advocates, like Professor Will Steffen from the Climate Council, are stressing the need for government action.
"Australia is really one of the global laggards on climate change. We've got no leadership on the issue. We've got no plans in place. We've got no policies in place at the national level to do our fair share. Fortunately states and territories and cities are starting to take action on their own."