After Hurricane Michael and Hurricane Florence damaged the east coast of the United States, thousands of people continue to recover from the destruction.
According to the United States Census Bureau, the hurricane affected Maryland, North Carolina, South Carolina, Virginia, Florida, Georgia, and the District of Columbia, potentially impacting (directly or indirectly) almost 85 million people.
To understand why this hurricane was so devastating, let’s go back to how they form: Hurricanes start off with warm water in the tropics. Winds blow dust from the Sahara desert into the eastern Atlantic Ocean, triggering a condensation of the humidity in the air, which begins the storm.
The condensing water creates heat, warming the ocean underneath, which causes even more evaporation and condensation, thus creating an endless cycle that inflates the storm. Such hurricanes only stop when they encounter cold water or land (which cut off its supply of warm water).
However, when they move inland, they cause damage in three significant ways:
“One is [that] the storm literally pushes the ocean higher ahead of it, [in] what’s called storm surge,” biology teacher Mike Pistacchi said. “As the storm moves onto land, that creates the equivalent of massively high tide, [which] causes a lot of coastal damage.”
Second, the high wind speeds of the hurricane demolish buildings and cars.
“The third one is, once all that water dumps onto the land,it all has to make its way back to the sea, which creates all kinds of flooding,” Pistacchi said. “So low lying coastal communities like North Carolina are very, very vulnerable to… this deluge of water coming back down to the ocean.”
Furthermore, according to data from the National Oceanic and Atmospheric Administration (NOAA) website, tropical storms are beginning to slow down and remain in place for longer. Storms may be compounded by the impact of increased population as well.
“As more and more people move to the coast, that could cause a real negative impact in the future,” said Dan Gregoria, a senior forecaster at the National Weather Service in San Diego.“You can’t stop a hurricane, [so] I would say the most important thing is for people moving [to the coast] to be informed.”
Global warming may lead to an increase in intensity of tropical storms and hurricanes, but itis not the sole factor governing the formation of these storms.
“Global warming–that’s a complicated question. Warmer water produces bigger hurricanes… and global warming will drive up ocean temperatures.There’s no doubt about that correlation,” Pistacchi said. “That being said, whether or not we’ll get more storms depends on global climate patterns, which are also being altered by climate change. Right now, if anyone says ‘this storm was because of global warming’ it’s probably an oversimplified view of it. But the general picture is definitely on track with bigger storms.”
Though the connection between climate change and hurricanes has not yet been fully explored, the correlation is clear.
“All of the climate models have predicted if not more frequent hurricanes, hurricanes of greater magnitude. So greater magnitude is obviously going to do more damage than a more mild hurricane and so that definitely seems to be playing out,”upper school biology teacher Kate Schafer said. “Scientists have already developed the tools to calculate how much greater magnitude a hurricane is because of the already-felt effects of climate change.”