As expected, Earth’s average surface temperature in 2023 was the warmest on record, as confirmed by the analysis of different bodies such as the National Aeronautics and Space Administration (NASA) of the U.S., the National Oceanic and Atmospheric Administration (NOAA) also of the U.S. and the Copernicus Climate Change Service of Europe. This is not surprising considering that new monthly temperature records were set every month between June and December last year.
According to scientists from NASA’s Goddard Institute for Space Studies (GISS), global temperatures in 2023 were around 1.2 degrees Celsius above the average for NASA’s baseline period (1951-1980). The NOAA on the other hand measured it at 1.18 degrees C, the highest global temperature among all years in their 1850-2023 climate record. The Copernicus Climate Change Service of Europe also ranked 2023 as the warmest year on record.
Meanwhile, the United Nation’s World Meteorological Organization (WMO) which uses six leading international datasets from across the globe to monitor global temperatures, reveal a new annual temperature average of 1.45°C set against the pre-industrial era (1850-1900). That’s very near the 1.5°C limit set by the Paris Agreement. The WMO said that each decade has been warmer than the previous one and the past nine years have been the warmest on record.
Furthermore, the NOAA said that the 2023 upper ocean heat content, which addresses the amount of heat stored in the upper 2,000 meters of the ocean, was the highest on record. Ocean heat content is a key climate indicator because the ocean stores 90% of the excess heat in the Earth system. The 2023 annual Antarctic Sea ice extent (coverage) averaged 3.79 million square miles in 2023, the lowest on record. The maximum extent in September was 6.55 million square miles, which was the lowest by a record margin.
The long term rise in the emission of greenhouse gases in the atmosphere is the main driver of this record heart and was worsened by the El Niño phenomenon in the Pacific Ocean. From 2020-2022, the Pacific Ocean saw three consecutive La Niña events and in May 2023, the ocean transitioned from La Niña to El Niño. Other phenomena that can affect yearly or multi-year changes in climate are aerosols or fine particles and volcanic eruptions.
There is bad news. The record temperatures in the second half of 2023 occurred before the peak of the current El Niño event. Scientists expect to see the biggest impacts of El Niño in February, March, and April. This means there is a possibility that 2024 will be worse than last year.
The NOAA predicted there is a one in three chance that 2024 will be warmer than 2023 and a 99 percent certainty that 2024 will rank among the five warmest years ever. Climatologist Gavin Schmidt, director of the NASA GISS, put it at about 50-50, that’s 50 percent chance it’ll be warmer and 50 percent chance it will be slightly cooler.
Let’s prepare for a very hot summer!