The hurricane season is heating up again. What happens when we run out of names?
The 2021 Atlantic hurricane season was expected to be above average, and so far it has been delivered.
A total of 17 named storms crossed the Atlantic Basin this year. Most memorable for Canadians was Hurricane Larry, which hit eastern Newfoundland two weeks ago, while the most powerful, Ida, peaked in Category 4 and hit Louisiana in the end of August.
Now, it seems, the 18th storm is almost upon us. Tropical Depression 18 formed west of Cabo Verde on Wednesday, and forecasters are optimistic the storm will reach at least tropical storm status, and potentially hurricane status by the weekend.
If he crosses this threshold, he will receive the name Sam.
The hurricane season traditionally runs from June 1 to November 30, with substantial flexibility on either side of this beach. With more than two months to go, future Storms have plenty of time to devour the three remaining names on the 2021 roster. In fact, once that happens, it will be the second consecutive season to do so.
Once the 21st storm comes and goes, what do we call the 22nd and beyond?
In the past, forecasters switched to the Alternate Greek Alphabet, starting with Alpha and working your way up. The first time this happened was in 2005, with 28 storms in total, six of which were given Greek names. The last, Zeta, ended up lingering for a few days in 2006, and the season as a whole has been the most active so far.
Fifteen years later, 2020 has surpassed this season. A total of 30 named storms raged in the Atlantic Basin, eight of which received Greek designations. This is where the Greek name system, probably intended to be a little-used overflow, began to crumble.
The World Meteorological Organization has a long-standing policy of removing the names of storms that cause significant damage and death. In 2020, three storms qualified: Laura, Eta and Iota.
Since the letters of a given alphabet usually do not have readily available alternatives in the same language, WMO announced earlier this year that it would simply compile a list of Latin alternative names in the future, ending the use of the Greek alphabet after only its second season of use.
In 2021, a hypothetical 22nd storm would be named Adria, and would follow from the list below.
In the years to come, this kind of overflow could become more frequent.
No individual storm can be attributed to climate change, but it has long been proven that climate change makes extreme weather more common.
The number of storms also seems to be gradually increasing. Every 10 years or so, forecasters will review and update the 30-year storm averages, and they have gradually increased.
From 1961 to 1990, for example, the annual average was 10 named storms, of which 5 to 6 were hurricanes, and less than two were major hurricanes of Category 3 or above.
In the 1991-2020 range, these numbers had increased to 14-15 named storms per year, of which 7-8 were hurricanes and just over three were Category 3 or above.
Averages being what they are, not all years will follow these exact numbers, with some having fewer storms and others more.
Yet the trend is undeniably upward so far, which communities will need to plan for over the next century.