During the vice presidential debate on Wednesday, Republican incumbent Mike Pence claimed that there are no more hurricanes today than there were 100 years ago. Is this true? Only partly, as our graphic shows: While the number of hurricanes varies from year to year, the number of major hurricanes of a category 3 or above on the Saffir-Simpson scale has increased since the 1960s, as our graphic shows.
Hurricane Delta, currently approaching the coast of Louisiana, is the third major hurricane (Cat. 3) of the ongoing 2020 season, and the ninth hurricane in the year overall. It looks like 2020 will end up being a busy year for hurricanes, while 2019 was rather subdued at only six hurricanes. Yet, half of the hurricanes that formed in the Atlantic basin in 2019 were major hurricanes – a trend that started in the late 1990s.
The number of hurricanes in categories 3-5 on the Saffir-Simpson scale has increased from on average of around 1.6-1.7 per year in the 1970s and 1980s to an average of 3.0-3.6 per year in the 2000s and 2010s. Climate change has been identified as a reason why stronger hurricanes occur.
More evidence that hurricane seasons are changing can be deferred from the tropical storms that never turn into hurricanes but are named by National Oceanic & Atmospheric Administration upon reaching a certain strength. This year, the season’s first storm – Arthur – was named on May 15 after forming near the Bahamas. This made 2020 the sixth consecutive year that a named storm formed before the start of the official season on June 1. 2020 also saw 25 storms reach naming strength, which caused administrators to run out of names at storm 22, at which point they resorted to the Greek alphabet.
Earlier this year, category 4 storm Laura brought destruction and flooding to Louisiana. The storm was the strongest by wind speed to ever hit the U.S. coast, tying with a 1856 hurricane which also made landfall in the state. The third major cyclone of the season, hurricane Teddy (Cat. 4), did not make landfall as such.
2005, when Hurricane Katrina struck New Orleans, was the worst hurricane seasons since 1851, records from the National Oceanographic & Meteorological Laboratory at NOAA show. Hurricane Katrina was just one of seven major hurricanes observed in the Atlantic basin that year, making almost half of all tropical cyclones in 2005 major hurricanes. 2005 was the year with most hurricanes in the Atlantic (15), followed by 2010 (12), including Hurricane Sandy, and 1969 (also 12).
This chart shows the number of hurricanes over the Atlantic basin by category (1967-2020).