Climatologists say the idea of putting a “climate price tag” on an individual storm could help the public understand how global warming directly affects them. This is especially true in places like North Carolina, which continues to see a boom in coastal development even as hurricane severity worsens under climate change, says Hans Paerl, professor of marine and environmental sciences at the ‘University of North Carolina at Charlotte. “Coastal watersheds are the most affected by flooding, and rising sea levels make the water problem worse,” he says. “It brings the water further inland.”
Paerl looked at historical flood and precipitation records since the late 1800s and found that catastrophic hurricane-induced flooding had increased dramatically over the past 20 years, according to a 2019 study published in the journal. Scientific reports on nature. The study concluded that there had been a change in historical weather patterns which now bring more rain to the coastal region during each storm.
In recent years, these floods and rains have washed pork waste from North Carolina pig farms to nearby waterways, damaging coastal ecosystems and valuable commercial fisheries. But worsening flooding hasn’t stopped people from moving to the area, says Paerl, who has lived in Beaufort, North Carolina, for 40 years. “Real estate is booming. People still want to build houses here. “
And coastal residents don’t even have to face flooding issues related to climate change. Floods that occur when the sky is clear – so called harmful floods– are also on the increase in cities like Miami; Norfolk, Virginia; and Charleston, South Carolina, according to a study published in March. These researchers found that of 40 coastal tide gauges operated by NOAA, nearly half had measured more days of harmful flooding since the mid-19th century due to higher local tides. Cities built along estuaries showed the greatest tidal changes, the result of sea level rise combined with dredging operations to deepen ports for shipping.
As the number and intensity of tropical storms in the Atlantic Ocean have increased in recent years, NOAA officials were forced in April to recalculate their statistical average for a “normal” hurricane season. The new normal is now 14 tropical storms, down from a previous annual average of 12. This adjusted figure includes seven storms that eventually become powerful enough to be classified as hurricanes. (Once a tropical storm’s winds reach 74 miles per hour, it’s nicknamed a Category 1 hurricane. From there, hurricanes progress to Category 5, packing winds of 157 mph, according to the Saffir-Simpson hurricane wind scale.)
Last year was a record-breaking Atlantic season, with 30 tropical storms, 13 of which became hurricanes. NOAA officials are expected to announce their forecast for 2021 on Thursday, but in the meantime, the commercial weather forecasting company DTN, which provides data to airlines, farms, trucking companies and other weather-dependent industries, predicts another above-average season with 20 tropical storms, nine hurricanes and four major hurricanes with a Category 3 strength or higher, says Renny Vandewege, the company’s vice president of weather operations.
“We think the east coast of the United States is more threatened this year, whereas in 2020 it was more in the western Gulf of Mexico,” says Vandewege. “This year, we think it’s more along the Florida coast, through the Carolinas, and then through the northeastern United States as well.”
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