July 2021 was the hottest month in the last 142 years, that is, since we began regularly monitoring the temperature of our planet. The news was announced by climatologists at the National Oceanic and Atmospheric Administration (Noaa), the American agency for oceanic and atmospheric observation.

Combining land surface and ocean surface temperatures, Noaa estimated that last month saw an average of 16.73 degrees Celsius, or 0.93 degrees above the twentieth-century average, which stands at around 15.8 degrees. Moreover, the record temperature recorded is 0.01 degrees higher than the previous record set in July 2016 (which had already been equalled in 2019 and 2020).

The last time a July was, on the contrary, cooler than the twentieth-century average was in 1976. That was also, at the same time, the last year that was cooler than the average. "This means that anyone under 45 has never experienced a year (or a July) in which the planet's average temperature was cooler than the twentieth-century average," Gabriel Vecchi, a climatologist at Princeton University, told the Associated Press.

July 2021, the latest instance of an increasingly worrying trend

July 2021 marks the latest instance of an increasingly worrying trend: in the last seven years, from 2015 to 2021, the seven hottest Julys on record have all been recorded. "This new record adds to the disturbing and disruptive path that climate change is charting," commented Rick Spinrad, Noaa's chief oceanographer.

It is land masses that are recording the most worrying temperature increase: we are talking about an average of 1.54 degrees Celsius above the 2012 figure. In particular, Asia recorded its hottest July on record, surpassing the previous record set in 2010, while for Europe it was the second hottest, after 2018 and tied with 2010.

2021 in the top ten hottest years on record

According to the Global annual temperature rankings outlook from Ncei (National Centers for Environment Information), 2021 is very likely to rank among the ten hottest years ever recorded worldwide. But unlike Noaa, the European agency Copernicus believes that July 2021 was "only" the third hottest on record, and not the first as the American agency indicates. According to the Europeans, July 2021 would rank behind July 2019 and July 2016 (higher by 0.1 degrees Celsius) and tied with July 2020.

However, Copernicus agrees with the American organisation in stating that the month just passed is the second hottest July on record for the European continent. Copernicus also added that the Baltic areas and those of the eastern Mediterranean experienced "severe heatwaves", while Northern Ireland "broke its daily maximum temperature record". Above-average temperatures were also recorded in Iceland and Greenland.

Heat records in Italy and Spain too

And following the European temperature record of 48.8 degrees reached in Syracuse, Sicily, an exceptional heatwave struck Spain, where the town of Montoro, in the province of Córdoba, set the new heat record for the European nation: 47.4 degrees. It is in fact the first time that the alert system of the Agencia estatal de meteorología (Aemet) has recorded such a high temperature. Until now, 45 degrees had never been exceeded.

All the data gathered by Ncei and Noaa arrive just days after the publication of the first part of the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (Ipcc), according to which the actions taken at a global level to drastically cut greenhouse gas emissions are still insufficient. If further proof were needed, this is yet another demonstration of how necessary it is to step up efforts to mitigate the effects of climate change. And how urgent it is to accelerate in order to achieve concrete results.