Storm Classification (bring on the Greeks) - 2005 vs 2020 vs Standards?

[EquusStorm]

Should have posted that link, my apologies; 1983-present NHC advisories are at HERE ; select NHC on the pull down menu, or NWS Miami for the earlier dates, and select the date of the storm in question for essentially their full text product suite. NHC only has 1991-1995/1998-present in their archive so that's a pretty handy resource.

Mom came up for a bit and showed me some more photos, I think their power came back on today and water came back a couple days ago so things are looking up I think. Was quite a storm!

[Ptarmigan]

Here's the thing, I think NHC is actually a lot more conservative and careful than they used to be. It's just that super primitive technology of past years led to numerous missed storms that should have been classified. Yeah, maybe subtropical cyclone classification standards are more generous now, but that's a whole different thing.

Forecast discussions from NHC are available all the way back to 1983 on Iowa State Mesonet; it's clear we've come a dramatically long way in forecasting and analysis reading these. Amazing how many discussions for tropical depressions in the 1980s essentially begin with "well there's a circular looking blobby cloud with a tropical wave in the tropics on low res IR that looks like a depression so we'll forecast a hurricane because waters are warm" and then two advisories later, "well we sent a plane out and there is no evidence whatsoever of a closed circulation or any organization whatsoever and probably never was so, uh, final advisory"; other storms go straight from depression or weak TS to hurricane with a discussion like "well the blob we thought was a depression got an eye so oops it's a hurricane now I guess" - the extreme difficulty in locating centers not under convection without daytime visible imagery led to a lot of nighttime complete uncertainty where forecasters essentially just said "well gotta wait for morning to know if we even have a circulation or where the center would even be if it's actually a TC"; forecast track and intensity errors were constant and tremendous with some storms, but really no fault with the forecasters who were certainly extremely knowledgeable and very well versed in tropical weather, just very primitive technology to help with that.

For 2005 specifically, looking closely at loops, everything that should have been classified probably was, though there was an interesting nor'easter type system off the East Coast in May that could possibly be considered a subtropical system today. I think the standards are pretty much the same at least for tropical cyclones, but more generous with subtropical storms now that we can analyze them better. 2005 just had a ton of quality storms and less high latitude brief stuff than we have the last couple years.

It's not that we're getting more now, it's that we've missed a ton in the past; just eyeballing some 1980s seasons show multiple high latitude systems all year that would likely get named with better analysis techniques. Even as recently as 1992, 1994, and 1997 it's highly likely we missed 2-3 storms that should have been classified. So it's pretty asinine to force today's far more advanced classification ability to hold itself back to a time with primitive technology that would miss numerous storms just because we simply couldn't analyze them properly... yeah, a few subtropical storms now certainly may not have gotten named a while back, but a check on the 1970s seasonal maps show numerous subtropical storms classified over the open Atlantic, so we certainly classified a lot of them at some point. Consistency would be nice, but hey, no database is perfect. It's simply impossible to compare modern seasons to past seasons when technology is so different!

For the record I am of the full belief that any >35kt warm core cyclone with a closed center and associated convection, or the subtropical equivalent thereof, should be classified no matter the latitude or duration. Ignoring them is a complete disservice to science and climatology. There are zero named storms that should not have been named (a few cases like Colin and Jerry that come up frequently, possibly borderline given the inconsistency of the surface center) but I can think of several that probably should have been, just subjectively weren't due to strict standards. Classifying more weak storms with better tech probably means the named storm to hurricane ratio gets significantly skewed in modern seasons, but that just means the new ratio is a far more accurate picture of the actual true ratio of basin activity, given how many weak storms we used to miss.

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This kind of has me wondering just how quiet the "quiet period" in the 70s, 80s, and early 90s really was. Maybe still slower than it is now, but likely not as slow as was thought. Suppose we went back in time to that time period again, but with the technology we have now. I wonder what those seasons would look like.

I noticed in the 1970s, there were many depressions. For example, 1979 had 26 tropical depressions. There were 9 storms, 5 hurricanes, and 2 major hurricanes. 1977 had 16 tropical depressions and that was an inactive season. Makes me wonder if there were actually more tropical storms in the past. That includes even recent season of the 2000s to 2010s.

https://en.wikipedia.org/wiki/1977_Atla ... ane_season
https://en.wikipedia.org/wiki/1979_Atla ... ane_season

[Ptarmigan]

2005 and 2020 had many storms. There are differences. 2005 had 5 major hurricanes by end of September. So far, there are 2 major hurricanes. The first major hurricane of 2005 was Dennis in July. Three of the five major hurricanes by end of September are Category 5's; Emily, Katrina, and Rita. The first major hurricane of 2020 is Laura in August.

The Accumulated Cyclone Energy (ACE) in 2005 is so far much higher than 2020. I would like to see how much energy 2005 has produced. One can use Integrated Kinetic Energy (IKE), which would require tropical storm and hurricane force wind extent, which is not available for all seasons. One could look at radius of outermost closed isobar (ROCI) and calculate how much energy it produces. Another is Power Dissipation Index (PDI).

[canes92]

2005 was by far a qualitative season. 2020 not nearly so as there have been more short lived depressions or tropical storms rather than major hurricanes.