The Atlantic hurricane season is underway, and scientists are warning that while global warming has not increased the number of these powerful storms, climate change is making such tempests more energetic and destructive.
The term ‘hurricane’ is actually a regional word for tropical cyclones of a certain intensity that form over the North Atlantic and eastern North Pacific Oceans.
Warmer ocean temperatures provide more energy to hurricanes, which are fueled by the heat energy released when water vapor condenses into clouds. As ocean temperatures rise, hurricanes can draw on more heat energy, which makes them stronger.
Warmer air can also hold more water vapor. This means that hurricanes can produce more rain, which can lead to flooding.
In addition, warmer air is less dense, which can weaken the vertical wind shear. Vertical wind shear is a difference in wind speed and direction between different altitudes. It can disrupt the formation and development of hurricanes. As the air warms, the vertical wind shear weakens, which makes it easier for hurricanes to form and grow stronger.
By warming the oceans, climate change is not creating more hurricanes, but it is making hurricanes stronger. That’s because warmer seawater supplies more heat to a hurricane, increasing its wind speed.
Experts class hurricanes in 5 categories, with category 1 being the weakest and 5 the strongest. Since 1979, climate change has increased the risk that a storm will develop into a ‘major’ hurricane—at least category 3, with winds over 110 mph—by around 5% every ten years.
The combination of these factors is making hurricanes more powerful and destructive. The Atlantic has seen an increase in the number of major hurricanes (Category 3 or higher) in recent decades, and the trend is expected to continue as climate change progresses.
This is a serious threat to coastal communities, which are already facing the effects of sea level rise. Hurricanes can cause widespread damage, including flooding, wind damage, and power outages. They can also lead to loss of life.
Tropical cyclones have caused, on average, $21 billion in damage a year since 1971, and since more people are moving to coastal areas, the number of people who are at risk has tripled in this time.
There are a number of things that can be done to reduce the risk of hurricane damage, such as: