Changes in Tropical Cyclone Intensity & Track

[GordMay]

Originally Posted by boatpoker

your link* was published in 2019. The weather changes have been drastic since then, they are outdated.

Although the climate/weather has been, and is, changing; I don't think the fundamental thermo- & fluid- dynamic relationships, that form the basis of forecasting models, have changed.
Only the inputs change, which [of course] change the outputs - but not the overall accuracy.
If anything, I would suspect that the accuracy of the weather models may have only improved, over the past 4 years, or so.

* “Profitable Prophecy: Advances in Weather Prediction” ~ by R.B. Alley, K.A. Emanuel, and F. Zhang
Link ➥ https://dspace.mit.edu/bitstream/han...v1.pdf?sequenc

[boatpoker]

Originally Posted by GordMay

Although the climate/weather has been, and is, changing; I don't think the fundamental thermo- & fluid- dynamic relationships, that form the basis of forecasting models, have
* “Profitable Prophecy: Advances in Weather Prediction” ~ by R.B. Alley, K.A. Emanuel, and F. Zhang
Link ➥ https://dspace.mit.edu/bitstream/han...v1.pdf?sequenc

Changing but not changing ... seems contradictory to me.
I guess we are going to disagree.

[GordMay]

Originally Posted by boatpoker

Changing but not changing ... seems contradictory to me.
I guess we are going to disagree.

By analogy:
We calculate speed, distance, or time, using the formula: D = ST, Distance Equals Speed times Time [or it’s transpositions].
Changing an initial input [S or T, or changing weather], will change the output [D, or changing weather forecast]; but it doesn’t change the accuracy of the equation.
So: changing, but, not changing.

[boatpoker]

Originally Posted by GordMay

By analogy:
We calculate speed, distance, or time, using the formula: D = ST, Distance Equals Speed times Time [or it’s transpositions].
Changing an initial input [S or T, or changing weather], will change the output [D, or changing weather forecast]; but it doesn’t change the accuracy of the equation.
So: changing, but, not changing.

I believe the models have more than those three elements and are not nearly as simple as you seem to think..

[GordMay]

Originally Posted by boatpoker

I believe the models have more than those three elements and are not nearly as simple as you seem to think..

Originally Posted by boatpoker

your link was published in 2019. The weather changes have been drastic since then, they are outdated.

I’m aware of the complexity of weather [& climate] models; but was trying to present a simple, intuitively understandable explanation, of my position.

However, you may be right, about increasing difficulty, in forecasting, due to climate change.

As I previously posted
At ➥ https://www.cruisersforum.com/forums...ml#post3808142
“As the climate continues to warm, hurricanes may intensify more rapidly, just before striking land, making hurricane forecasting more difficult.
Kerry Emanuel’s study [1] of hurricanes found that it may be harder to predict hurricane intensity, in a warmer world. The reason is that, a hurricane can weaken, or strengthen, more rapidly than before, and things that change quickly are inherently hard to predict...”

[1]“WILL GLOBAL WARMING MAKE HURRICANE FORECASTING
MORE DIFFICULT?”~ by Kerry Emanuel
➥ https://texmex.mit.edu/pub/emanuel/P..._BAMS_2017.pdf

[chrisr]

there is some really interesting stuff here

www.ssd.noaa.gov/PS/TROP/TCFP/index.html

(taken from bob mcdavitt's weekly blog...a must for anybody with an interest in the weather of the south pacific)

cheers,

[Don C L]

Originally Posted by chrisr

there is some really interesting stuff here

www.ssd.noaa.gov/PS/TROP/TCFP/index.html

(taken from bob mcdavitt's weekly blog...a must for anybody with an interest in the weather of the south pacific)

cheers,

Or anywhere in the Pacific! Thanks for the link.

[GordMay]

For the first time, in the weather satellite era, each of the world’s 7 warm ocean basins have seen a scale-topping [category 5 equivalent] tropical cyclone, hurricane, or typhoon, so far in 2023.

While we’d typically see at least one tropical system, somewhere on Earth, achieve this infamous milestone each year, we’ve never seen each of the world’s tropical ocean basins pump out a scale-topping storm, all within the same year.

Many of the planet’s apex storms so far this year have been noteworthy for their ferocity, longevity, and the sheer speed at which they intensified.

Cyclone Freddy, the first Category 5 tropical cyclone of 2023, was a deadly powerhouse of a storm in the Indian Ocean, that’s likely to secure a spot in record books as the longest-lived [5 weeks & 2 days: Feb 6 ➛ March 14] tropical cyclone ever observed. Freddy peaked in strength, near the central Indian Ocean, several times, once, with sustained winds as high as 168 mph [270 km/h].

Jova formed far off the western coast of Mexico where it encountered very warm waters over the eastern Pacific Ocean. The system intensified from a tropical storm with 68 mph winds on September 5, 2023, into a Category 5 hurricane with 162 mph just 24 hours later. Jova was the first Cat 5 hurricane, to form in the eastern Pacific Ocean, since 2018.

The following day, Hurricane Lee over in the Atlantic Ocean accomplished a similar feat. Lee rapidly grew its maximum sustained winds from 81 mph to 168 mph over a 24-hour period, one of the fastest bouts of intensification ever observed over the Atlantic. Lee was the eighth Category 5 storm, to form in the Atlantic, since 2016.

But, the year’s strongest tropical system, to date, developed in the western Pacific Ocean, back in May. Super Typhoon Mawar [AKA: Betty, in The Philippines] swiftly grew into a monstrous Category 5 equivalent storm, when it peaked with maximum winds measuring as high as 183 mph.

The hot waters around Oceania gave rise to another Category 5 cyclone, at the end of February. Cyclone Kevin’s intense winds briefly reached the top of the scale, after traversing the islands of Vanuatu. Kevin formed around the same time as Cyclone Judy, another powerful storm that followed almost the same track as Kevin, just a few days earlier.

Cyclone Ilsa rapidly intensified, off the northwest Australian coast, in the middle of April, as it swirled toward landfall, near Port Hedland, which sits about 1,400 km north of Perth. Ilsa hit the coast with the equivalent strength of a major hurricane, but the sparse population led to minimal damage.

Cyclone Mocha rapidly intensified, in the northern Indian Ocean, during the middle of May. Mocha’s maximum winds of 172 mph made the storm one of the strongest on record, in this part of the world. The cyclone weakened, as it swept into land, unleashing deadly floods in Myanmar and Bangladesh.

[s/v Jedi]

I only research the tropical storms in the Atlantic as those are the ones that impact me, but I find that the models have improved for sure. Especially the GFS model is improving so much that I now check it regularly in addition to the Euro model which seemed to rule for years.

I notice most improvement of the GFS model in the past 3-4 years.

Not that it’s accurate enough… last year hurricane Ian was projected to hit Tallahassee in Florida, then continue weakened to Georgia but instead turned, crossed the peninsula and hit us on the space coast instead, after wreaking havoc on the Gulf coast. Dam storm took out our primary solar array.

[GordMay]

An interesting and informative retrospective, on hurricane ‘Ian’ [Sept 2022]
See the “FORECAST AND WARNING CRITIQUE”, beginning on page 14.

"Ian" Report ➥ https://www.nhc.noaa.gov/data/tcr/AL092022_Ian.pdf

”NATIONAL HURRICANE CENTER TROPICAL CYCLONE REPORT
HURRICANE IAN
(AL092022)
23–30 September 2022
Ian made landfall in southwestern Florida at category 4 intensity (on the Saffir-Simpson Hurricane Wind Scale), producing catastrophic storm surge, damaging winds, and historic freshwater flooding across much of central and northern Florida. Ian was responsible for over 150 direct and indirect deaths and over $112 billion in damage, making it the costliest hurricane in Florida’s history and the third-costliest in United States history. Ian also made landfall as a category 3 hurricane in western Cuba bringing widespread damage and loss of power to the entire island. Ian made its final landfall as a category 1 hurricane in South Carolina ...”

See also, the “Hurricane IAN Advisory Archive”
➥ https://www.nhc.noaa.gov/archive/2022/IAN.shtml

And the “5-day Forecast Track and Watch/Warning Graphic”
➥ https://www.nhc.noaa.gov/archive/202...y_cone_no_line

[donradcliffe]

I think the climate change priests keep moving the goalposts.

https://www.weather.gov/lwx/hurricane_history

1878 October 23 Not Named. A Category 2 hurricane hit the Washington/Baltimore region. This is the strongest storm to ever hit this region since record-keeping began in 1851.

[GordMay]

Originally Posted by donradcliffe

I think the climate change priests keep moving the goalposts.
https://www.weather.gov/lwx/hurricane_history
1878 October 23 Not Named. A Category 2 hurricane hit the Washington/Baltimore region. This is the strongest storm to ever hit this region since record-keeping began in 1851.

How does a [1878] hurricane, in the Washington/Baltimore region, “move the goalposts”?

[Mike OReilly]

My apologies if this paper has already been cited here, but I thought this fit the thread:

A recently published journal article reports that hurricanes in the Atlantic basin have increased their tendency to get worse (intensify) by more than 25% in recent decades. What this means is that more storms are being boosted into higher intensity depressions.

Here's the paper:

Observed increases in North Atlantic tropical cyclone peak intensification rates

And here's a news article which might be easier to read:

Hurricanes are growing more intense along Atlantic seaboard, study finds

This matters to all of us who ply the waters of the Atlantic. Even folks like me who spend all our time out of the so-called hurricane zone are seeing the effects. I've been hit by two in the last three years while in Newfoundland, and had a 1/2 dozen near-brushes.

[GordMay]

A fun fact about hurricanes:
If it's not from the Hurricagne region of France, it's just a sparkling tropical system.

[GordMay]

Proposed New Category 6 for Hurricanes — because they already exist

A new peer-reviewed study [1], published Monday, in [PNAS] Environmental Sciences, examined storm data, between 1980 and 2021, and found five storms that could have been classified as Category 6 [Category 6
192 mph/309 km/h, or higher] — all of them occurring in the final nine years of the study period.

Beyond past storms, the study modelled and simulated the potential futures, to find a "statistically significant" trend of storms, that could reach this hypothetical Category 6.

Tropical cyclone risk messaging is a very active topic, and changes in messaging are necessary, to better inform the public, about inland flooding and storm surge, phenomena that, a wind-based scale is only tangentially relevant to. While adding a 6th category to the Saffir–Simpson Hurricane Wind Scale would not solve that issue, it could raise awareness, about the perils of the increased risk of major hurricanes due to global warming.
"Our results are not meant to propose changes to this scale, but rather to raise awareness that the wind-hazard risk from storms presently designated as Category 5 has increased and will continue to increase under climate change.”

While most recorded storms, that would fit this hypothetical category, were in the western Pacific, the ingredients [hot ocean temperatures, high humidity, warm atmosphere and low wind shear[ all exist in the Atlantic, too.

Research also suggests storms are getting more powerful more quickly. Another study [2], published last October, found that tropical storms [or a Category 1 hurricane] were increasingly likely, to develop into a Category 3 or 4, within a 24-hour period.
Previous studies have, also, found an increase in rapid intensification.
The National Hurricane Center considers a storm to rapidly intensify, if it increases wind speed by 35 mph (46 kph), in 24 hours.

Any change in the scale, would require the support of the U.S. National Hurricane Center (NHC), based in Miami, and it is not in favour of the idea.

[1] “The growing inadequacy of an open-ended Saffir–Simpson hurricane wind scale in a warming world” ~ by Michael F. Wehner & James P. Kossin
➥ https://www.pnas.org/doi/10.1073/pnas.2308901121

"SIGNIFICANCE:
Global warming leads to more intense tropical cyclones (TCs). Three separate lines of evidence from both observations and models suggest that the open endedness of the 5th category of the Saffir–Simpson hurricane wind scale becomes increasingly problematic for conveying wind risk in a warming world. We investigate considering the extension to a 6th category of the Saffir–Simpson hurricane wind scale to communicate that climate change has caused the winds of the most intense TCs to become significantly higher...”

[2] “Observed increases in North Atlantic tropical cyclone peak intensification rates” ~ by Andra J. Garner
➥ https://www.nature.com/articles/s41598-023-42669-y