Why 2024 could become the hottest year on record

For some Europeans it might be hard to believe that the Earth has broken a new temperature record. While parts of America, Asia, the Middle East and indeed southern Europe have suffered deadly heatwaves, many European countries have been soaked by record rainfall that has made summer feel dreary. Temperatures in parts of western Europe have been around or below average in June. But data from Copernicus, the EU’s Earth-observation programme, show that globally, it is sweltering. Average global air-temperature records have been broken on two consecutive days. On July 22nd air temperatures reached 17.16°C (62.89°F), breaking the record of 17.09°C set just one day prior. The previous record of 17.08°C had stood since only July 6th 2023.

The biggest influence on the Earth’s temperature, aside from global warming, is the El Niño-Southern Oscillation (ENSO), a natural phenomenon that affects weather patterns worldwide. El Niño, the hot phase of ENSO, led to the record-breaking temperatures of 2023 and has only recently come to an end. One of the areas driving up the global average is Antarctica. Temperatures around the South Pole are much higher than usual (see map), which is also a factor in the record-low sea ice for this time of year—when it is winter in the southern hemisphere.

One record rarely comes alone. In 2023 global temperatures reached a new high on four consecutive days. In 2016 the record was broken seven times; in 1998, six. This is the third year in which records set just one year earlier were broken. (Proper record-keeping began in 1940.)

The world has now seen record monthly temperatures for 13 months in a row; every month since July last year has been more than 1.5°C above the temperature typical for the corresponding month in the second half of the 19th century. Given that, in the Paris agreement of 2015, world leaders set themselves the task of “pursuing efforts to limit the temperature increase to 1.5°C above pre-industrial levels”, does this mean their efforts have definitively failed? Not quite yet. It is widely agreed that the limit will not be passed until a multi-year trend breaks the 1.5°C level.

The second half of the year may not be quite as extraordinary as the first. The World Meteorological Organisation reckons that there is a 70% chance that La Niña, the cold phase of ENSO, could begin some time between August and November. It should herald cooler temperatures. But there is still a very good chance that, overall, 2024 will clock in as hotter than 2023.

© 2024, The Economist Newspaper Ltd. All rights reserved. 

From The Economist, published under licence. The original content can be found on www.economist.com