In a conclusive declaration, scientists affirm that Earth experienced its warmest year in 150 years, providing irrefutable evidence of the escalating global temperature crisis. The relentless surge in temperatures began gaining momentum midway through the year, shattering records month after month.
Quoting the European Union’s Copernicus Climate Change Service, last year’s global temperatures averaged 1.48 degrees Celsius (2.66 Fahrenheit) higher than the second half of the 19th century, surpassing the previous record-holder, 2016. NASA and the National Oceanic and Atmospheric Administration (NOAA) concurred, with NASA reporting a 1.37-degree Celsius rise from preindustrial levels and NOAA indicating a 1.34-degree Celsius increase over the preindustrial average.
Despite variations in methodology, the consensus is unanimous: 2023 stands out as the hottest year on record by a considerable margin. Russell Vose, Chief of Climate Monitoring and Assessment at NOAA National Centers for Environmental Information, remarked, “This is a big jump,” underscoring the gravity of the situation during the announcement of the agency’s findings.
The link between unrestrained greenhouse gas emissions and the surge in global temperatures comes as no surprise to climate scientists. The burning question now is whether 2023 signifies the onset of a trend where heat records are not just broken but obliterated, suggesting an acceleration in the planet’s warming.
Carlo Buontempo, Director of the European Union climate monitor, added a historical perspective, noting that when combining satellite readings with geological evidence, 2023 ranks among the warmest years in at least 100,000 years. “There were simply no cities, no books, agriculture, or domesticated animals on this planet the last time the temperature was so high,” he emphasized.
Each tenth of a degree in global warming amplifies thermodynamic fuel, intensifying heatwaves, storms, and contributing to rising seas, along with hastening the melting of glaciers and ice sheets. The repercussions were vividly apparent in 2023, with scorching temperatures affecting Iran, China, Greece, Spain, Texas, and the American South. Canada bore witness to its most devastating wildfire season on record, consuming over 45 million acres. Additionally, less sea ice formed around the coasts of Antarctica, both in summer and winter, than ever before.
NOAA’s Chief Scientist, Sarah Kapnick, stressed the need for preparedness in the face of climate change impacts, urging communities, businesses, and individuals to utilize the released data to build resilience for the future.
Under the 2015 Paris Agreement, nations pledged to restrict long-term global warming to 2 degrees Celsius, with an aspirational goal of 1.5 degrees. However, current greenhouse gas emission rates are on track to render the 1.5-degree target unattainable in the near future.
While carbon dioxide and other greenhouse gases remain the primary drivers of global warming, 2023 saw additional natural and human-induced factors contributing to the temperature surge. The underwater volcano eruption near Tonga in 2022 released substantial water vapor into the atmosphere, trapping more heat. Limits on sulfur pollution from ships also reduced aerosol levels, tiny particles that reflect solar radiation and aid in cooling the planet.
Another significant factor was El Niño, a cyclical shift in tropical Pacific weather patterns, often associated with global heat records. However, the unusual timing of last year’s El Niño, starting midyear, suggests it was not the primary driver of the abnormal warmth, leaving scientists wary of potentially higher temperatures in 2024.
Climate scientists caution against drawing sweeping conclusions from a single exceptional year like 2023. Nonetheless, other indicators point to an accelerated pace of global warming. Approximately 90 percent of the energy trapped by greenhouse gases accumulates in the oceans, and recent data indicates a significant acceleration in the oceans’ heat uptake since the 1990s.
Sarah Purkey, an oceanographer at the Scripps Institution of Oceanography, highlighted the non-linear nature of this acceleration, suggesting a rapid increase. In France, a group of researchers found that Earth’s overall heating across oceans, land, air, and ice had been accelerating since 1960, aligning with the trends of increased carbon emissions and reduced aerosols in recent decades.
However, scientists acknowledge the need for continued research to comprehend potential additional factors at play, emphasizing that “something unusual is happening that we don’t understand,” according to Karina von Schuckmann, an oceanographer at Mercator Ocean International in Toulouse, France.