Posted inOxford News

2020 had warmest September on record, data shows

According to monthly data collected by the Copernicus Climate Change Service (C3S), September 2020 was the warmest on record, with global average surface air temperatures 0.05 degrees warmer than 2019, and 0.63 degrees warmer than the average between 1981-2010.

Credit: Copernicus Climate Change Service/ECMWF.

Its report found that many of the world’s regions experienced exceptionally warm Septembers:

  • Siberia continued a series of above-average months, which have seen wildfires in the region, whilst temperatures over the Arctic Ocean as a whole were warmer than usual.
  • The Middle East saw record temperatures reported in Turkey, Israel and Jordan in September, with Israel experiencing eight consecutive days higher than 40 degrees Celsius.
  • North America too experienced temperatures significantly above the average; maximum daytime values reached 49 degrees in Los Angeles County earlier in the month, whilst wildfires in the state of California alone have burned more than 4 million acres of land.
  • South America witnessed higher temperatures especially in Paraguay and southern Brazil, where wildfires have severely damaged the world’s largest tropical wetland, the Pantanal.
  • The Antarctic also saw predominantly above average temperatures when compared to 1981-2010 averages.

In Europe, where average temperature anomalies are generally larger and more variable than global data, the September average was also the highest on record, at 1.8 degrees above the 1981-2010 average, and 0.2 degrees above the value for the same month in 2018, which was the previous warmest September.

On a wider scale, Copernicus also reports on temperatures over the last 12-month period, in this case from October 2019 to September 2020. Global average temperatures over this period were nearly 1.3 degrees above the pre-industrial level, just 0.2 degrees away from the 1.5-degree threshold that the 2015 Paris Agreement endeavoured to keep below.

The report says that there is general agreement between datasets regarding a general increase of 0.2 degrees in global average temperatures per decade since the late 1970s. Further, the last six years, from 2015, have all been noticeably, or exceptionally, warm.

The data show how close the world is coming to the 1.5-degree barrier, which, if breached, could set in motion a series of unpredictable yet devastating feedback mechanisms and lead to tipping points being passed.

Once such tipping point is fast-approaching in the Amazon rainforest, with research released this week showing that as much as 40% of the forest is now at a point where it could exist as savannah, rather than rainforest. Whilst this process takes decades to complete, it is happening faster than previously thought, and the process is difficult to prevent once set in motion.

Due to climate change, parts of the rainforest, which is home to 10% of all the world’s known species, as well as three million indigenous people, are receiving significantly less rainfall. The Amazon has witnessed its worst fires in a decade in 2020, with a 60% in fire hotspots compared to 2019.

This is reflective of wildfires across the world this year, from Australia’s devastating bushfires in which three billion animals were killed or displaced, to fires in America which have become a major subject in the US presidential election.