Climate negotiations often revolve around keeping the rise in average global temperatures to a maximum of 2°C above pre-industrial levels. Warmer than this, it is said, and climate change-induced natural disasters will increase dramatically in severity, causing untold damage to life and property, alongside shrinking the habitability of environments across the globe. According to the U.K.’s Met Office, we’re set to pass the halfway mark by the end of this year, as global average temperatures are due to breach 1°C above pre-industrial levels.
This comes as 2015 is also set to be the warmest year on record, as well as the prediction that 2016 will be the first year when global atmospheric concentrations of carbon dioxide will hit 400 parts per million. The news precedes the upcoming UN climate talks in Paris in a month's time, where world leaders will attempt to come to an agreement on a deal to cutting global greenhouse gas emissions.
The Met Office is able to draw on a massive data set of temperatures from as far back as the 1800s, and then average the temperatures recorded between 1850 and 1900 to calculate pre-industrial temperatures. A few years ago the Intergovernmental Panel on Climate Change found that the average global temperature had increased by 0.85°C between 1880 and 2012, but this new research shows how this has continued to rise. During the first nine months of 2015, the global mean temperature hit 1.02°C, with a margin of error of 0.11°C either side, with three months still to go in the year.
It is thought that a combination of increasing carbon emissions and the especially strong El Niño have contributed to this particularly warm year. The World Meteorological Organization reported how carbon dioxide and methane emissions reached record levels last year, while the current El Niño hitting the Pacific is also one of the worst on record.
“This year marks an important first, but that doesn't necessarily mean every year from now on will be a degree or more above pre-industrial levels, as natural variability will still play a role in determining the temperature in any given year,” the Head of Climate Monitoring and Attribution at the Met Office, Peter Stott, said in a statement. “As the world continues to warm in the coming decades, however, we will see more and more years passing the 1°C marker – eventually it will become the norm.”
It is, however, still achievable to limit the warming to below 2°C. While research suggests that we have currently released around two-thirds of the total carbon dioxide emissions allowed to stay below 2°C, the sooner global emissions peak, the earlier they should start to be brought under control.