A new analysis of heat wave patterns concludes that climate change driven by the buildup of human-caused greenhouse gases will overtake natural variability as the main cause of heat waves in the western United States by the late 2020s and by the mid-2030s in the Great Lakes region.

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A new analysis of heat wave patterns concludes that climate change driven by the buildup of human-caused greenhouse gases will overtake natural variability as the main cause of heat waves in the western United States by the late 2020s and by the mid-2030s in the Great Lakes region.