Sea surface temperatures across the tropical Atlantic are much warmer than average, and vertical wind shear is well below average. So conditions still support the idea of more tropical cyclones yet to come.
Teddy made landfall near Ecum Secum, Nova Scotia , and has become completely extra tropical with winds of 50 mph. Beta is a remnant low. And Paulette’s ghost has been sent the way of Linda Blair. But other than that the tropics are quiet….and most likely will stay that way for the next 7-10 days. So I want to discuss something else………
I read an article by Eric Holthaus titled “ The 2020 Hurricane Season Is a Turning Point in Human History”
Mr Holthaus is a meteorologist and a Climate correspondent. In the article Holthaus claims, due to the record setting pace of naming tropical cyclones in the Atlantic that “ We’ve entered a brand-new, catastrophic era”. He also said “At no point in the 170 years of Atlantic basin weather history have so many strong storms formed so quickly”. Another thing he pointed out was “This hurricane season has been defined by storms forming in strange locations that rapidly intensify and produce unusually heavy rains” He is using all the typically buzz words such as Apocalypse and Terrifying.
I will provide a link to his article at the end of this post, so you can read it, and draw your own conclusions.
The question is Eric Holthaus correct in what he is implying? … Or is he using smoke and mirrors like a David Copperfield magic show?
We’ve seen two tropical cyclones in the Gulf at the same time, We’ve had 9 tropical cyclones make landfall on the CONUS. We had an Medicane in the Mediterranean (A Medicane is a hurricane like storm that forms in the Mediterranean). We’ve seen some very slow-moving tropical cyclones that dropped a lot of rain on local communities. We’ve seen systems getting named in places in the North Atlantic over cold water. And most importantly, we’ve had 23 named storms so far this season, the truth is we’re running about 30 days ahead of an average season in regards to the NHC naming tropical cyclones.
So far it seems Holthaus is right……at least at first blush looking at the surface of the data he presents. There was an important piece of data that was left out of the article, Accumulated Cyclone Energy (ACE). I’ve explained what ACE is many times… So all I will say is “It’s a metric used to express the energy used by a tropical cyclone during its lifetime. The total ACE of each storm is added up to come up with the seasonal ACE”.
Most people base how active the hurricane season on the number of named storms. While this is OK…it really isn’t the best way to measure how active a season truly is. it really shows us how much tropical energy the atmosphere was able to produce during a hurricane season.
1933 saw the highest total ACE in recorded history, with an ACE of 259. 2005 comes in at Second place, with an ACE of 250.
Global ACE is currently at 62% of normal year-to-date. In an average year, the Pacific makes up the lion share of the ACE. But this year that distinction is being held by the North Atlantic. So, this means the other basins are running way below average to date As of today (September 23) ACE values in the North Atlantic are running about 145% above average for this date. Now that may seem like a lot, but it really is only slightly above average based on the climatical average using the 1980 to 2010 average. On average the ACE index for the Atlantic Basin, ends up right around 104. As of today, the ACE value in the Atlantic is 105.
This data below comes from the CPC and NOAA.
Extremely active season:
An ACE index above 152.5 x 104 kt2 (corresponding to 165% of the 1981-2010 median).
Above-normal season:
An ACE index above 111 x 104 kt2 (corresponding to 120% of the 1981-2010 median), with at least two of the following three conditions: 13 or more named storms, 7 or more hurricanes, and 3 or more major hurricanes.
Below-normal season:
• a) An ACE index below 66 x 104 kt2 (corresponding to less than 71.4% of the 1981-2010 median), or
• b) An ACE index above 71.4% of the median with the following three conditions: 9 or fewer named storms, 4 or fewer hurricanes, 1 or fewer major hurricanes.
Near-normal season: Neither the above- nor below-normal season criteria are met.
A near-normal season will typically have an ACE range of 66-111 x 104 kt2 (corresponding to 71.4%-120% of the 1981-2010 median).
We’ve had a lot of named storms, but not really a lot of activity. Three quarters of the systems this season have been short-lived, very weak one- or two-day wonders. Now I know we have two months left in the Atlantic season. I’ve been saying we’re not done with tropical cyclones this season. I still think the Northeast and or Mid Atlantic will see at least one more tropical impact this season. And IMO the Caribbean is ripe for a major hurricane to develop, from there it could go into the Gulf or along the Eastern Seaboard. But even with that, If we were to remove some of the short-lived, weak and questionably-named systems, our ACE would be 75.9. Which would be right around average for this date. So again IMO, if the next two months were to match what we’ve seen so far, we would most likely still end up slightly above average at the end of the season.
So, based on this, I think Eric Holthaus nose has been growing of late.
I want to point out that, this is all based on statistical analysis, and isn’t any indictor of the potential daily, weekly, or seasonal threats of Atlantic hurricanes and tropical storms for the rest of this season.
Very informative, Thank you.
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