2023’s Billion-Dollar Disasters List Shattered the U.S. Record with 28 Big Weather and Climate Disasters Amid Earth’s Hottest Year on Record

Phoenix went 30 days with daily high temperatures at 110 F (43.3 C) or higher and recorded its highest minimum nighttime temperature, with temperatures on July 19 never falling below 97 F (36.1 C).

Although heat waves result from weather fluctuations, global warming has raised the baseline, making heat waves more frequent, more intense and longer-lasting.

That heat also fuels wildfires.

Increased evaporation removes more moisture from the ground, drying out soil, grasses and other organic material, which creates favorable conditions for wildfires. All it takes is a lightning strike or spark from a power line to start a blaze.

How Global Warming Fuels Extreme Storms
As more heat is stored as energy in the atmosphere and oceans, it doesn’t just increase the temperature – it can also increase the amount of water vapor in the atmosphere.

When that water vapor condenses to liquid and falls as rain, it releases a large amount of energy. This is called latent heat, and it is the main fuel for all storm systems. When temperatures are higher and the atmosphere has more moisture, that additional energy can fuel stronger, longer-lasting storms.

Tropical storms are similarly fueled by latent heat coming from warm ocean water. That is why they only form when the sea surface temperature reaches a critical level of around 80 F (27 C).

With 90% of the excess heat from global warming being absorbed by the ocean, there has been a significant increase in the global sea surface temperature, including record-breaking levels in 2023.

Higher sea surface temperatures can lead to stronger hurricanes, longer hurricane seasons and the faster intensification of tropical storms.

Cold Snaps Have Global Warming Connections, Too
It might seem counterintuitive, but global warming can also contribute to cold snaps in the U.S. That’s because it alters the general circulation of Earth’s atmosphere.

The Earth’s atmosphere is constantly moving in large-scale circulation patterns in the forms of near-surface wind belts, such as the trade winds, and upper-level jet streams. These patterns are caused by the temperature difference between the polar and equatorial regions.

As the Earth warms, the polar regions are heating up more than twice as fast as the equator. This can shift weather patterns, leading to extreme events in unexpected places. Anyone who has experienced a “polar vortex event” knows how it feels when the jet stream dips southward, bringing frigid Arctic air and winter storms, despite the generally warmer winters.

In sum, a warmer world is a more violent world, with the additional heat fueling increasingly more extreme weather events.

Shuang-Ye Wu is Professor of Geology and Environmental Geosciences, University of Dayton. This article is published courtesy of The Conversation.This article, originally published Dec. 19, 2023, was updated Jan. 9, 2024, with NOAA’s disasters list.