The planet is experiencing the hottest summer ever – for the second year in a row

CNN
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As scientists confirmed, summer has broken global heat records for the second year in a row, putting 2024 on track to be the hottest year on record.

The period between June and August – summer in the Northern Hemisphere – was the world's hottest such period since weather records began in 1940, according to data released Friday by Copernicus, the European service measuring climate change.

This summer was 0.69 degrees Celsius warmer than the 1991-2020 average, beating last summer's previous record by 0.03 degrees, Copernicus found.

It is the latest in a series of global heat records, but it will not be the last, scientists warn, as humanity continues to mine planet-warming fossil fuels and drive up global temperatures.

The impacts and toll on human health and life were clear: countries around the world endured brutal summer temperatures that fueled deadly heatwaves, record-breaking wildfires and destructive storms.

Even in the southern hemisphere winter the heat was extreme.

Last month, Australia broke its national record for the hottest day in August, reaching a temperature of 41.6 degrees Celsius (106.9 Fahrenheit). Meanwhile, temperatures in parts of Antarctica rose 50 degrees Fahrenheit above normal in July.

The Copernicus data confirm what seemed likely after the planet experienced its hottest June on record, followed by the hottest single days in July on record.

The summer was crowned with the hottest August ever, Copernicus confirmed on Friday.

With an average temperature of 16.82 degrees Celsius (62.28 Fahrenheit), it was 1.51 degrees Celsius warmer than an average August in the pre-industrial era, before humanity began burning large amounts of fossil fuels.

Overall, the 12 months from September 2023 to August 2024 were the hottest ever recorded in a seasonal period, and 1.64 degrees Celsius warmer than pre-industrial levels, Copernicus found.

“This series of record temperatures increases the likelihood that 2024 will be the hottest (calendar) year on record,” said Samantha Burgess, deputy director of Copernicus, in a statement.

There are a number of factors that lead to fluctuations in global temperatures. These include natural climate patterns such as El Niño, which originates in the tropical Pacific and has a planet-warming effect, as well as human-caused factors such as the burning of fossil fuels – the main driver of the climate crisis.

El Niño, which was responsible for the record temperatures, ended in June, but scientists say its effects will not stop immediately.

“This summer's record heat was expected due to the persistent heat from the waning El Niño event, which has contributed to ongoing warming from greenhouse gas emissions from human activities,” said Richard Allan, professor of climate science at Britain's University of Reading.

Allan told CNN that it was “extremely worrying” that global warming had been 1.5 degrees Celsius above pre-industrial levels over the past 12 months, but that this was “inevitable” given the slow pace of government action to reduce planet-warming pollution.

Scientists have long warned that global warming must be limited to 1.5 degrees above pre-industrial levels to avert the most catastrophic effects of climate change.

While they are more concerned about long-term violations – spanning decades rather than single years – the steady increase in temporary violations is an alarming indication of where the world is heading and what that means for people's lives.

Burgess of Copernicus warned that much worse was to come.

“This summer's temperature-related extreme weather events will become even more severe and have more devastating consequences for people and the planet unless we take urgent action to reduce greenhouse gas emissions,” she said.