April 2025 was the second warmest month on record, and it was also the 21st time in the last 22 months that the average global surface air temperature was more than 1.5°C above the monthly pre-industrial level, the European Union’s (EU) Copernicus Climate Change Service said on Thursday.
It was also the second-warmest April globally, with an average surface air temperature of 14.96°C, 0.60°C above the 1991-2020 average for April.
April was 1.51°C above the estimated 1850-1900 average used to define the pre-industrial level. The 12-month period of May 2024 – April 2025 was 0.70°C above the 1991-2020 average, and 1.58°C above the pre-industrial level.
“Globally, April 2025 was the second-hottest April on record, continuing the long sequence of months over 1.5ºC above pre-industrial. Continuous climate monitoring is an essential tool for understanding and responding to the ongoing changes of our climate system,” said Samantha Burgess, Strategic Lead for Climate at European Centre for Medium-Range Weather Forecasts (ECMWF).
Also Read: March 2025 second warmest on record, says EU climate agency
Temperatures were predominantly above average across Europe, with the largest warm anomalies recorded over eastern Europe, western Russia, Kazakhstan, and Norway, while colder-than-average temperatures occurred across Türkiye, eastern parts of Bulgaria and Romania, the Crimean Peninsula, and northern Fennoscandia.
Outside Europe, temperatures were most above average over the Russian Far East and in a large part of west-central Asia. They were also above average over most of North America, part of Australia, and across the Antarctic Peninsula and West Antarctica.
The average sea surface temperature (SST) for April was the second highest on record for the month, 0.15°C below the April 2024 record. SSTs remained unusually high in many ocean basins and seas. Among them, large areas in the northeast North Atlantic continued to show record-high SSTs for the month. Most of the Mediterranean Sea was also much warmer than average.
Arctic sea ice extent was 3% below average, the sixth lowest monthly extent for April in the 47-year satellite record. Antarctic sea ice extent was 10% below average, making it the 10th lowest on record for the month.
Overall surface temperature data shows temperatures have come down compared to last year but not substantially.
Long-term global warming is currently estimated to be between 1.34 and 1.41°C compared to pre-industrial levels, the World Meteorological Organisation’s State of the Global Climate report said in March.
“The issue is we currently do not have an agreed mechanism to monitor global temperature rise in the context of the Paris Agreement goals. For example, which data set to go by, how do we define warming– surface temperature or air temperature, there are number of questions around this. So how quickly we will breach the 1.5°C goal is difficult to answer. In 2023-2024 temperatures have been higher than expected compared to background warming. It’s being studied if this is a result of reduction in aerosols from certain sectors,” a WMO expert said during a technical briefing on the report.
The Paris Agreement sets long-term goals to guide all nations to substantially reduce global greenhouse gas emissions to limit the global temperature increase in this century to 2°C while pursuing efforts to limit the increase even further to 1.5°C, to avoid or reduce adverse impacts and related losses and damages.