Have you ever wondered why you don't hear as much about tornadoes or typhoons or even water spouts occurring in the rest of the world as you do in the U.S.? There's a good reason for that, and the answers are geography and global warming.
Unlucky Geography
Historically, the U.S. gets hit by stronger costlier, more varied and more frequent extreme weather than anywhere else on Earth. We can look at the "perfect storm" of geographic conditions that contribute to creating nasty weather:
Two oceans
The Gulf of Mexico
The Rocky Mountains
Jutting peninsulas like Florida, Texas, and the coasts of South and North Carolina
According to Victor Gensini, a meteorology professor at Northern Illinois University, bad weather in the U.S. "starts with kind of two things. Number one is the Gulf of Mexico. And number two is elevated terrain to the west."
When the dry air from the west blows up and over the Rocky Mountains, it crashes into warm, moist air from the Gulf of Mexico and creates a stormy jet stream. "That doesn't happen really anywhere else in the world," Gensini notes.
The United States also sits between two contrasting northern and southern climates called the mid-latitudes, which get the most interesting weather due to clashing colder northern temperatures and warmer southern jet streams. When these hit the West to East Jet streams, tornadoes, derechos, and other severe storms result.
While the Midwest and northern parts of the country experience severe storms, the Southern U.S. bears the brunt of mother nature's wrath. Every extreme weather event that exists affects the South, including wildfires, tornadoes, floods, hurricanes, derechos, and water spouts. According to University of Georgia meteorology professor Marshall Shepherd, "There's no other place in the United States that can say that."
The South is also more vulnerable because it has the highest number of manufactured housing which is vulnerable to weather hazards and storms, particularly as these usually strike at night when people can't see them and are less likely to take cover.
Weather is Becoming More Extreme
The main driver of extreme weather has been an intensified water cycle. The water cycle is the way we track moisture moving through the climate system. It includes everything from oceans, clouds, ice, rivers, lakes, and groundwater and how these transfer water from place to place. Intensification of this cycle means the water/moisture is being moved around more quickly and in greater quantities. So, when it rains, it comes down harder and faster than before.
With intensification comes more energy, which means more heat. As temperatures rise, the air holds more moisture, and when this air moves over a region, it has greater energy to suck up even more moisture from the ground.
Couple this with our geography, and some areas become dryer and prone to drought as warm air passes over them, while other areas see flash flooding and intense rainfalls. For example, the U.S. has been seeing drought in areas west of the Rockies, and more intense water events east of the mountain range for the past several years.
Scientists are not only concerned with the severity of weather events but also the frequency at which these extremes occur, how long they last, their seasonal timing and spatial extent. By studying weather patterns that occurred prior to man-made influences and comparing them with the weather patterns of today, meteorologists can identify the increased chances of extreme weather because of human influences and more quickly predict events.
What Can Be Done
Experts suggest a number of ways communities and residents can improve their chances of recovering from catastrophic weather events and help prevent worsening conditions:
Don't build in floodplains. Most U.S. cities, with the possible exception of Denver, are built near water and are susceptible to storm surges and flash flooding.
Rebuild our infrastructure to survive the storms, not simply meet standard requirements.
Reduce emissions.
Sources: Insurance Journal, The Verge,
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