The winter of 2023 is poised to potentially be the hottest on record, in the wake of an already sweltering summer and warm fall.
A recent study in the journal Advances in Atmospheric Sciences indicates a 95% likelihood that this winter will set a new high for global average surface temperatures, particularly in the U.S. and Eurasia.
This projection aligns with the United Nations' announcement of 2023 as the hottest year ever recorded.
Between June and October 2023, average global temperatures were 0.57 degrees Celsius (1.03 degrees Fahrenheit) above the 1991-2020 average.
August and September were particularly warm, surpassing their monthly averages by 1.2 and 1.24 degrees Fahrenheit, respectively.
Petteri Taalas, chief of the U.N.'s World Meteorological Organization, highlighted the unprecedented nature of these climatic changes, noting record highs in greenhouse gas levels, global temperatures, and sea level rise, alongside record lows in Antarctic sea ice.
The predicted warmth for this winter is attributed to a moderate to strong eastern Pacific El Niño event.
El Niño, which occurs every two to seven years due to warming ocean waters and weakened trade winds, shifts the Pacific jet stream towards the U.S. West Coast. A "strong" El Niño is characterized by water temperatures at least 1.5 degrees Celsius (2.7 degrees Fahrenheit) above average.
These conditions are expected to lead to increased anticyclone activity in the Northwest Pacific, resulting in unusual winter weather patterns across North America and East Asia.
The U.S. Climate Prediction Center (CPC) forecasts a 35% chance of a historically strong El Niño between November 2023 and January 2024, and a greater than 55% chance of a strong El Niño lasting until March 2024.
This year's El Niño could push the average global temperature beyond the 1.5-degree Celsius (2.7 degrees Fahrenheit) threshold established at the 2015 COP21 conference.
According to Taalas, it's almost certain that the 1.5-degree mark will be reached temporarily within the next four years and could become a permanent condition in the following decade.
