In September, the temperature was 0.93C warmer than the average September temperature between 1991-2020, and 0.5C warmer than the previous record set in 2020.

The El Nio weather event, alongside ongoing emissions of warming gases, are driving the heat.

The scale of the increase shocked some scientists.

The year 2023 is now “on track” to be the warmest on record. As soaring temperatures show no sign of abating in the northern hemisphere, September’s high mark follows the hottest summer ever.

According to the Copernicus Climate Change Service, the month had the biggest jump from the long term average since 1940.

Some of the data’s details have shocked scientists.

Zeke Hausfather, an experienced researcher, wrote on X formerly known as Twitter, “This month was absolutely gobsmackingly bananas,” in his professional opinion. Even though some parts of the globe are beating a long-term recent average by almost a degree, this masks even greater differences. Across Europe, for example, heating exceeded the long-term average by 2.51C.

After a record summer, September’s temperatures have broken records by an extraordinary amount, according to Dr Samantha Burgess, Deputy Director of the Copernicus Climate Change Service (C3S). The difference between current temperatures and what they were before fossil fuel use is an important measure used by climate researchers.

The temperatures last month were around 1.75C higher than they were during this so-called pre-industrial period.

Researchers will be uneasy about this.