The harmful consequences of climate change have been more evident than ever in 2023, a year that set many worrying records. According to climate monitoring service Copernicus, 2023 was the hottest year on record, with a rise in Earth’s surface temperature dangerously approaching the critical threshold of 1.5 degrees Celsius.
The heat waves, droughts and fires that have ravaged the planet are tangible signs of climate change. The global average temperature reached 1.48°C above the pre-industrial baseline, the Copernicus Climate Change Service (C3S) reported.
“This is also the first year where all days have been at least one degree warmer compared to pre-industrial times,” said Samantha Burgess, deputy director of C3S. “Temperatures in 2023 are likely to be the highest in at least 100,000 years.”
Nearly half the year has exceeded the 1.5°C limit, beyond which the consequences of climate change become more likely to become self-reinforcing and catastrophic, scientists say.
However, even if the Earth’s average surface temperature exceeds 1.5°C in 2024, as some scientists predict, this does not mean that the world has failed to meet the Paris Agreement’s goal of limiting global warming below this threshold.
This will only happen after several successive years above the 1.5°C baseline, and even then the 2015 treaty allows for the possibility of reducing Earth’s temperature after a period of exceedance.
The year 2023 has seen massive fires in Canada, extreme droughts in East Africa and the Middle East, unprecedented summer heat waves in Europe, the United States and China, as well as of record winter heat in Australia and South America.
“These events will continue to get worse until we move away from fossil fuels and reach net zero emissions,” said Ed Hawkins, professor of climate change at the University of Reading, who did not contributed to the report. “We will continue to suffer the consequences of our inactions today for generations.”
The Copernicus results come a month after a climate deal was reached at COP28 in Dubai, calling for a gradual transition away from fossil fuels, the main cause of global warming.
The year 2023 also set another grim record: two days in November exceeded the pre-industrial threshold by more than two degrees Celsius.
Copernicus predicts that the 12-month period ending in January or February 2024 will “exceed pre-industrial levels by 1.5 degrees Celsius”.
Overheating oceans
Reliable weather records date back to 1850, but older proxy data for climate change, from tree rings, ice cores and sediments, show that 2023 temperatures “exceed those of any period by at least 100,000 years,” according to Burgess.
Records have been broken on every continent. In Europe, 2023 was the second hottest year on record, with the temperature 0.17°C lower than 2020.
2023 marked the start of a natural El Niño weather phenomenon, which warms the waters of the South Pacific and causes higher temperatures. The phenomenon is expected to peak in 2024 and is linked to eight consecutive months of record heat from June to December.
Global ocean temperatures were also “persistent and abnormally high”, with many seasonal records recorded since April.
Rising concentrations of CO2 and methane
These unprecedented ocean temperatures led to marine heatwaves that were catastrophic for aquatic life and intensified the intensity of storms.
Oceans absorb more than 90% of excess heat caused by human activity and play a major role in regulating Earth’s climate.
Rising temperatures have also accelerated the melting of ice shelves, frozen ridges that help prevent the massive glaciers of Greenland and West Antarctica from sliding into the ocean and rising sea levels.
Antarctic sea ice reached record levels in 2023.
“The extremes we have observed in recent months provide spectacular testimony to the remoteness of the climate in which our civilization developed,” said Carlo Buontempo, director of C3S.
In 2023, concentrations of carbon dioxide and methane reached record levels of 419 parts per million and 1,902 parts per billion, respectively.
Methane is the second largest contributor to global warming after CO2 and is responsible for around 30% of the increase in global temperatures since the industrial revolution, according to UNEP.
We are at a critical turning point in the fight against climate change. 2023 has reminded us of the urgency of the situation and the importance of taking immediate action to reduce our dependence on fossil fuels and achieve net zero emissions. Time is running out, and we must act now to preserve our planet and future generations.