Humans are warming the planet – The first major review of the science of climate change since 2013. Its release comes less than three months before a key climate summit in Glasgow.

In strong, confident tones, the IPCC’s document says “it is unequivocal that human influence has warmed the atmosphere, oceans and land”.

The landmark report for the Intergovernmental Panel on Climate Change found human activity had already warmed the planet by 1.07C since the industrial revolution.

IPCC report key points

• Global surface temperature was 1.09C higher in the decade between 2011-2020 than between 1850-1900.
• The past five years have been the hottest on record since 1850
• The recent rate of sea level rise has nearly tripled compared with 1901-1971
• Human influence is “very likely” (90%) the main driver of the global retreat of glaciers since the 1990s and the decrease in Arctic sea-ice 

“We will hit one-and-a-half degrees in individual years much earlier. We already hit it in two months during the El Niño in 2016,” said Prof Malte Meinshausen, an IPCC author from the University of Melbourne in Australia. 

“The new report’s best estimate is the middle of 2034, but the uncertainty is huge and ranges between now and never.”

IPCC climate report: Code red for humanity

According to Prof Ed Hawkins, from the University of Reading, UK, and one of the report’s authors, the scientists cannot be any clearer on this point.

“It is a statement of fact, we cannot be any more certain; it is unequivocal and indisputable that humans are warming the planet.”

Prof Ed Hawkins, University of Reading

The new report also makes clear that the warming we’ve experienced to date has made changes to many of our planetary support systems that are irreversible on timescales of centuries to millennia. 

The oceans will continue to warm and become more acidic. Mountain and polar glaciers will continue melting for decades or centuries.

“The consequences will continue to get worse for every bit of warming,” said Prof Hawkins. 

“And for many of these consequences, there’s no going back.”

UNITED NATIONS WARNING

UN secretary-general Antonio Guterres said the report was a “code red’’ for humanity and the Paris Climate Change accord’s ambition of limiting global warming to 1.5C was “perilously close’’.

“The alarm bells are deafening, and the evidence is irrefutable: greenhouse gas emissions from fossil-fuel burning and deforestation are choking our planet and putting billions of people at immediate risk,’’ Mr Guterres said.