KMSP - It’s another day and another tropical system forms in the Atlantic. It’s now on to Nate which is a tropical storm near Nicaragua as I’m writing this and currently headed for an eventual U.S. landfall. Even without Nate on the charts, the 2017 season has been one of the busiest. Not necessarily in overall numbers, although getting to the “N” name is a feat in itself, but in overall energy expended.
There is an equation that takes the number of storms that form in the Atlantic (and around the world) and combines that with the time they have been a storm system along with their intensity. It’s this equation that gives us the Accumulated Cyclone Energy (ACE) for any one particular area. In this case, the Atlantic. We can use this equation to compare the amount of energy that was expended during the course of a season and compare it directly to another. It is done this way because even if 2 years had the exact same number of tropical systems, let’s say 10 for example, they wouldn’t be equal to each other at all because all of the storm won’t be the exact same intensity. One year may have 7 major hurricanes while the other year has none. The ACE would reflect that in the overall score.
The ACE for the 2017 season is now topping 200. This has only happened 8 other times in recorded history, the last time was back in the very busy season of 2004 and 2005. September actually set a record for the highest ACE in any one month. Only once has the score ever topped 250 and that was back in 1933. Even with such a busy season and the sheer number of very strong hurricanes, the numbers have not been going up over time, despite what you may think. The strongest hurricane recorded each year has NOT increased either since records began and neither has the number of major landfalling hurricanes. Now, there is some suggestions that stronger storms are more numerous than weaker storms now, but very little can back that up since one season has nothing to do with the other.