Earth experienced its hottest month on record in August, surpassing a critical climate threshold due to the combined effects of human-driven climate change and a powerful El Niño, according to data from the European climate service Copernicus.
This record-breaking heat also contributed to the hottest Northern Hemisphere summer ever measured, for both the globe and the United States. Globally, August averaged 62.53 degrees Fahrenheit (16.96 degrees Celsius). While this is technically a hundredth of a degree Celsius higher than the previous record set in July 2023, scientists consider it a tie due to the margin of error.
Globally, August was 1.65 degrees Celsius (nearly 3 degrees Fahrenheit) above pre-industrial levels, significantly exceeding the 1.5 degrees Celsius (2.7 degrees Fahrenheit) threshold established by the 2015 Paris climate agreement. The eight hottest months on record have all occurred since July 2023.
Samantha Burgess, strategic climate lead for Copernicus, noted that the climate system is operating outside expected ranges seen even a decade ago. She indicated that climate impacts are transitioning from abstract concepts affecting distant regions to disruptions affecting daily life, citing examples like school closures, overwhelmed hospitals, melting roads, and buckling train lines.
For the United States, August shattered heat records by more than half a degree Fahrenheit, with an average temperature of 75.58 degrees (24.21 degrees Celsius) and a record average daytime high of 88.56 degrees (31.42 degrees Celsius). July also set heat records in the U.S., breaking a long-standing mark from the Dust Bowl era.
Hottest Summer on Record
The contiguous United States experienced its hottest summer on record from June through August, averaging 74.37 degrees (23.54 degrees Celsius). This surpassed the previous record from the Dust Bowl year of 1936 by nearly four-tenths of a degree. Globally, this past summer tied with 2024 for the hottest on record.
Scientists suggest that the consistent breaking of temperature records, particularly with August setting an all-time mark over the traditionally warmer July, indicates an acceleration of human-caused climate change. Copernicus data dates back to 1940, while U.S. National Oceanic and Atmospheric Administration (NOAA) data for the United States extends to 1895, and global data, largely aligning with Copernicus, goes back to 1880.
Blame on Fossil Fuels and El Niño
While the El Niño phenomenon, characterized by the temporary warming of parts of the Pacific that influences global weather patterns, is a contributing factor, scientists emphasize that the primary driver of these extreme temperatures is the emission of heat-trapping gases from the burning of fossil fuels. Friederike Otto, a climate scientist at Imperial College London, stated that climate change intensifies every El Niño event, and continued reliance on fossil fuels will lead to further record-shattering months.
Burgess explained that El Niño typically adds only a tenth or two-tenths of a degree Celsius (two to four tenths Fahrenheit) to global temperatures, with the majority of the warming attributable to fossil fuel combustion. This particular El Niño is forecast to be exceptionally strong.
Experts warn that rising temperatures will likely lead to more frequent and severe heat waves, storms, floods, and wildfires. Climate scientist Zeke Hausfather projects that 2026 will likely surpass 2024 as the warmest year on record, with 2027 potentially reaching 1.8 degrees Celsius (3.2 degrees Fahrenheit) above preindustrial levels due to an unprecedented El Niño. Some individual days could even reach 2 degrees Celsius (3.6 degrees Fahrenheit) above mid-1800s levels.
United Nations climate chief Simon Stiell highlighted the consequences of continued fossil fuel consumption, including extreme heat, loss of life, economic costs, and disruptions to critical systems like transportation and health, as well as rising prices for basic goods. He described this as the price of humanity's addiction to fossil fuels and the resulting climate crisis.