Last year was the third or second warmest ever on record, with the planet also experiencing unprecedented sea level rises, greenhouse gas concentrations in the atmosphere, and Arctic sea ice loss.
That is according to the findings of 500 climate scientists from around the world, which show that only 2016 and 2015 could have had higher average global temperatures since records began in the mid- to late 1800s.
It was also found that 2017 was the hottest year ever to not feature the warming El Niño phenomenon, with Argentina, Uruguay, Spain, Mexico and Bulgaria all reporting record-high annual temperatures.
In a report overseen by the National Oceanic and Atmospheric Administration (NOAA), the scientists said the “remarkable” results also show that the growth rate of carbon dioxide in the atmosphere has nearly quadrupled since the early 1960s.
“The dominant greenhouse gases released into Earth’s atmosphere – carbon dioxide, methane, and nitrous oxide – increased once again in 2017, reaching new record highs,” the report says. "It was the warmest year not influenced by El Niño, as well as being warmer than any year before 2015.”
It was found that 2017's average CO2 concentrations were the highest ever in the modern 38-year global climate records, as well as in records created from ice-core samples dating back as far as 800,000 years.
Sea levels are approximately three inches higher than the 1993 average, and are now rising at a record-breaking rate of 1.2 inches per decade.
The findings also show that the maximum extent of Arctic sea ice coverage in 2017 was lower than at any point in 38 years, with the amount of September ice the eighth lowest on record and 25% less than the long-term average.
Antarctica also saw record-low sea ice coverage, which remained well below the 1981-2010 average, and fell to 811,000 square miles in March – the lowest recorded from daily satellite observations since 1978.
In addition, unprecedented multiyear coral reef bleaching starting in June 2014 continued to May 2017, resulting in more than 95% of coral dying in some affected reefs.
This comes separate research found that the world's oceans could become 75% more acidic by 2100 if global carbon emissions continue unabated, posing severe risks to marine life.
Cardiff University's Dr Sindia Sosdian, said: “Our new geological record shows us that, on our current emission trajectory, oceanic conditions will be unlike marine ecosystems have experienced for the last 14 million years.” Image credit: NOAA | iStock
