The 2021 Atlantic Hurricane season is swiftly approaching and the world waits nervously in anticipation of what is to come. You may recall that 2020’s season was deemed record-breaking, with 30 named storms and 12 making landfall in the United States. It was such an active hurricane season, that the entire roster of named storms was used up, and the US government consulted the Greek alphabet for names like Eta and Iota.
Luckily, most Caribbean islands were spared from devastating hurricane impact, with Tropical Storm Laura as the main threat that led to the death of 35 people in Haiti and the Dominican Republic. Yet, what can be expected as the season approaches?
Rethinking the “Average” Season
The 2017 and 2019 hurricane seasons were especially devastating in the Caribbean, acting as proof of global warming effects. The National Oceanic Atmospheric Administration (NOAA) has even begun to rethink the idea of what an “average” hurricane season is.
Variations in daily weather are calculated using averages based on 30-year periods. The NOAA will soon examine the extremely active period from 1991-2020 and compare it with 1981-2010. Research Associate at the University of Miami, Brian McNoldy, calculated that the average number of named storms would move from 12.1 to 14.4 if the benchmark changes. The average was 10 named storms 30 years ago.
Not only are the numbers likely to increase, but people can expect wetter and stronger storms. In short, an active hurricane season.
An earlier season?
Though the season commences June 1st annually, trends over the past few years have indicated that as temperatures in the Atlantic rise, storms are forming earlier. Over the last nine hurricane seasons, seven tropical storms were formed between May 15th and June 1st. Although they tend to be weaker than those formed in the peak of the season, those storms resulted in at least 20 deaths and cost over USD 200 million worth of damage (World Meteorological Organization).
There has not been a change to the hurricane season since 1965, but McNoldy says, “The Atlantic hurricane season has changed quite a few times in the past since the concept of a hurricane season came about. I don’t think there’s any harm in including the May 15 start date.”
Amendments have not yet been made but the National Hurricane Centre (NHC) will issue advisories from mid-May.
Outlook for 2021
Reports have already stated that there might not be an El Niño this year. “During El Niño, water across the eastern Pacific Ocean warms, making radical shifts to rainfall patterns. Showers subside over Indonesia and move to the eastern part of the Pacific. This results in strong thunderstorms forming, which influences wind patterns in the upper atmosphere, reducing wind shear in the Pacific and increasing it in the Atlantic.” (Palm Beach Post).
The effects of El Niño can be felt across the world; the last recorded El Niño of 2018 died just before Hurricane Dorian hit the Bahamas in September 2019.
What does this mean for the hurricane season?
Sea surface temperatures and other atmospheric conditions will now have a greater role in how the 2021 season unfolds. Jeff Masters, co-founder of Weather Underground and a writer for Yale Climate Connections explains, “Looking at ocean temperatures that are above average in the Caribbean and main development region, early signs are pointing to above average hurricane activity.”
More Greek names?
Should the 2021 Hurricane Season take over from the 2020 season, the WMO has called on the NHC to have more names on standby. The confusion caused by the Greek names last year has resulted in a complete ban on use. The Greek names were used once before for the extremely active season of 2005.
