How Climate Change is Changing Hurricane Season

By Jenevra Wetmore

So far this hurricane season there have been nine named tropical storms to hit the US. Four of them strengthened into hurricanes, and two reached major hurricane intensity (category 3 or higher). Most recently Hurricane Ian, one of the most powerful storms to ever hit the United States, struck the Florida coast and caused mass devastation. Ian brought winds of 150 mph accompanied by heavy rains and a storm surge. Downgraded to a tropical storm, Ian then moved across central Florida. 2.5 million people lost power, and more than 100 people lost their lives.

Scientists predict that, as climate change worsens, so will the intensity of hurricanes. In order to form, hurricanes need warm ocean water, moist air, vertical wind shear (change in wind speed as you travel upwards in the atmosphere), and a pre-existing disturbance like a cluster of thunderstorms. The combination of these four ingredients, according to NASA, is what makes the perfect storm, so to speak. In a world warmed by climate change there is more moisture in the atmosphere. Think of a pot of water put on the stove to boil– as the water gradually heats more water vapor escapes into the air in the form of steam. According to NOAA, temperatures in some parts of the Caribbean hovered around 90 degrees (more than 1.8 degrees Fahrenheit warmer than usual) as Hurricane Ian was forming, and these unusually warm waters were at least in part responsible for the intensity of the hurricane.

According to scientists, while the frequency of hurricanes and storms is not increasing, the intensity of hurricanes is, and will continue to worsen due to climate change. In the past few years there have been multiple storms that, like Ian, rapidly intensified before making landfall. Rapid intensification occurs when a tropical cyclone’s maximum sustained winds increase by at least 35 mph in a 24-hour period (tropical cyclones are what can become hurricanes). It was once unusual for storms to keep strengthening until landfall, but there are roughly 25 percent more rapidly intensifying storms in the Atlantic and Eastern Pacific now than 40 years ago. Noru, which recently hit the Philippines, was one of the most rapid storm intensifications that scientists have ever seen before: the storm’s winds accelerated from 50 miles per hour to 155 miles per hour within a day.

The eye of Hurricane Ian, September 28, 2022. (NASA: Landsat 8 satellite image.)

In addition to increasing intensity, research shows that hurricanes are now moving more slowly. This might sound like a good thing, but is far from positive; when hurricanes move slowly, they have the opportunity to drop more rain. The mechanism causing this slowdown is still being debated, but the effects are devastating. 

Sea level rise will also increase the severity of hurricanes, making storm surge flooding even worse for coastal communities. Sea level is predicted to rise 1-12 inches in the next 30 years and anywhere from 2-7 feet by the end of the century, depending on our future greenhouse gas emissions. Rising sea levels will push flooding further inland, causing even more destruction.

As we ride out the rest of hurricane season it is important to acknowledge that hurricanes do not affect everyone equally. BIPOC (Black, Indigenous, and people of color) and low-income people are at a disproportionate risk of hurricanes. These communities are more likely to live in neighborhoods with poor housing stock that are vulnerable to damage from natural disasters. When Hurricane Katrina hit New Orleans communities of color were the most impacted and were more likely to be below sea level. Additionally, though New Orleans called for mandatory evacuation, many low-income residents had no way of leaving the city or lacked the funds to do so; a 2011 study determined that 93% of those stranded in the days following the storm were Black. We continue to see these trends as more hurricanes hit, and it is indicative of an environmental justice problem. Environmental justice seeks to address the disproportionate exposure of historically marginalized communities to environmental harms. We see again and again how disadvantaged communities are the most impacted by climate change, and hurricanes are often a prime example.

It is essential that we curb our carbon emissions now to prevent worse disasters down the line. Cutting emissions would minimize sea level rise, helping to prevent higher flood levels. This would also help preserve coastal wetlands such as the Everglades, which are biologically diverse and fragile ecosystems. Lastly, cutting our carbon pollution would be a way to address environmental justice concerns so that the most historically marginalized and vulnerable people don’t continue to bear the brunt of the climate crisis.

What can you do?

  • Donate to the American Red Cross.
  • To help victims of hurricane Ian, donate to Feeding Florida, Florida Disaster Fund, and many more.
  • To help those impacted by Hurricane Fiona, donate to orgs such as Brigada Solidaria del Oeste or Global Giving’s Hurricane Fiona Relief Fund. 
  • Take steps to reduce your carbon emissions.


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