2023 was the hottest year on record

Climate change has intensified the occurrence of heatwaves, droughts, and wildfires globally, causing the global thermometer to rise by 1.48 degrees Celsius above the preindustrial baseline, according to a report from the Copernicus Climate Change Service (C3S). Samantha Burgess, deputy head of C3S, highlighted that 2023 marked the first year where every day surpassed one degree warmer than the pre-industrial era, with temperatures likely exceeding those of any period in the last 100,000 years.

Approximately half of the year exceeded the 1.5-degree Celsius limit, a threshold beyond which climate impacts are more prone to become catastrophic, according to scientists. However, breaching the 1.5-degree mark in 2024, as some scientists predict, does not necessarily imply a failure to meet the Paris Agreement target of limiting global warming below that threshold.

Such a failure would only be confirmed after several consecutive years above the 1.5-degree benchmark, and the 2015 treaty even allows for the prospect of reducing Earth’s temperature following a period of “overshoot.”

An additional alarming record for the year was noted: in November 2023, two days surpassed the preindustrial benchmark by more than two degrees Celsius.

According to Copernicus projections, the 12-month period ending in January or February 2024 is expected to surpass 1.5 degrees Celsius above the pre-industrial level.

In 2023, significant events included extensive fires in Canada, severe droughts in the Horn of Africa and the Middle East, unprecedented summer heatwaves in Europe, the United States, and China, as well as record winter warmth in Australia and South America.

Researchers emphasize that these events will persist and worsen until there is a transition away from fossil fuels and the achievement of net-zero emissions. The consequences of current inaction will continue to impact generations to come.

The release of the Copernicus findings comes a month after the conclusion of COP28 in Dubai, where a climate agreement was reached, advocating for a gradual shift away from fossil fuels, identified as the primary driver of climate warming.

Weather records have been reliably documented since 1850, but older proxy data derived from sources such as tree rings, ice cores, and sediment indicate that temperatures in 2023 “surpass those of any period in at least the last 100,000 years,” as stated by Burgess.

Noteworthy records were shattered on every continent. In Europe, 2023 ranked as the second-warmest year on record, trailing 2020 by a margin of 0.17°C.

The onset of a naturally occurring El Niño weather phenomenon marked 2023, leading to warmer waters in the southern Pacific and contributing to heightened temperatures globally. This phenomenon is anticipated to peak in 2024 and is associated with eight consecutive months of record heat from June to December.

Global ocean temperatures remained persistently and unusually high throughout the year, with numerous seasonal records broken since April. These elevated ocean temperatures resulted in destructive marine heatwaves, impacting aquatic life and intensifying storms.

Oceans, responsible for absorbing over 90% of excess heat generated by human activities, play a crucial role in regulating Earth’s climate. The rising temperatures further accelerated the melting of ice shelves, crucial frozen formations that help prevent significant glaciers in Greenland and West Antarctica from entering the ocean, ultimately raising sea levels. Antarctic sea ice reached record-low levels in 2023.

In 2023, concentrations of carbon dioxide and methane reached record levels of 419 parts per million and 1,902 parts per billion, respectively. Methane, identified as the second-largest contributor to global warming after CO2, has been responsible for approximately 30% of the rise in global temperatures since the industrial revolution.