© Timberline LodgeTimberline Lodge webcams, located on Mt. Hood, Oregon, capture fresh snowfall on June 16th, 2024.
The World Weather Attribution (WWA) group studied excess heat between May and early June, when the U.S. heatwave was concentrated in south-west states including California, Nevada and Arizona.
Extreme temperatures in Mexico also claimed lives during the period.
Such attribution studies take some time to complete, so it is too soon for scientists to say how much of a role climate change is playing in the current heatwave stretching from the centre of the U.S. through to the north-east and into Canada.
In their new report, the scientists said such a heatwave was now four times more likely than it was in the year 2000, driven by planet-warming emissions.
Many extreme weather events including heatwaves are becoming more frequent and intense as a result of climate change, experts say.
"The results of our study should be taken as another warning that our climate is heating to dangerous levels," said Izidine Pinto, Researcher at the Royal Netherlands Meteorological Institute.
"Potentially deadly and record-breaking temperatures are occurring more and more frequently in the U.S., Mexico and Central America due to climate change.
"As long as humans fill the atmosphere with fossil fuel emissions, the heat will only get worse - vulnerable people will continue to die and the cost of living will continue to increase."
The WWA study focused on a region including the US south-west and Mexico, as well as Guatemala, Belize, El Salvador and Honduras which also saw dangerously high temperatures.
— BBC
Comment: Wide temperature swings are one sign that base-line weather patterns forcasters have relied on for over a century are becoming deranged. This increasing chaos in the system is seen by some as the precursor to another Ice Age.