Changes in Tropical Cyclone Intensity & Track

[barnakiel]

The suggestion about a pole-ward shift is interesting. I must study this.



b.

[GordMay]

Originally Posted by barnakiel

The suggestion about a pole-ward shift is interesting. I must study this.
b.

You won't be the first to study this.

For instance:

Over the past 30 years, the location where tropical cyclones reach maximum intensity, has been shifting toward the poles, in both the northern and southern hemispheres, at a rate of about 35 miles, or one-half a degree of latitude, per decade, according to the study, “The Poleward Migration of the Location of Tropical Cyclone Maximum Intensity”
➥ https://www.ncdc.noaa.gov/news/tropi...g-toward-poles

“Poleward migration of the destructive effects of tropical cyclones during the 20th century” Jan Altman et al
➥ https://www.pnas.org/content/115/45/11543

“Recent poleward shift of tropical cyclone formation linked to Hadley cell expansion” ~ by S. Sharmila & K. J. E. Walsh
➥ https://www.nature.com/articles/s41558-018-0227-5

“Enhanced understanding of poleward migration of tropicalcyclone genesis” ~ by Kaiyue Shan and Xiping Yu
➥ https://iopscience.iop.org/article/1...326/abaf85/pdf

“Weak Tropical Cyclones Dominate the Poleward Migration of the Annual Mean Location of Lifetime Maximum Intensity of Northwest Pacific Tropical Cyclones since 1980" ~ by Ruifen Zhan and Yuqing Wang
➥ https://journals.ametsoc.org/view/jo...-17-0019.1.xml

However:
“A Recent Reversal in the Poleward Shift of Western North Pacific Tropical Cyclones” ~ by Y. Sun et al
➥ https://agupubs.onlinelibrary.wiley....9/2018GL079686

[barnakiel]

Originally Posted by GordMay

You won't be the first to study this.

For instance:


(...)

THX, Gord! I will read the material. This all suggests the trades and the currents shifted too. Perhaps something to use in crossing the Atlantic next time.


barnakiel

[Exile]

Originally Posted by barnakiel

THX, Gord! I will read the material. This all suggests the trades and the currents shifted too. Perhaps something to use in crossing the Atlantic next time.


barnakiel

According to the first (NOAA) article (didn't read the others), the shift in storms only applies to the Pacific & Indian Oceans, and there's no evidence of this occurring in the Atlantic. Sounds like a high level of certainty that this is occurring in those regions, but less certainty over the cause. The scientists attributing it to human causes believe it's some combo of CC, ozone depletion, and/or atmospheric pollution.

[Tin Tin]

Uh oh and I thought melting icebergs were a sign of global warming not a lead in to an ice age. It seems from this article we need to warm the oceans to prevent the next ice age.

https://www.sciencedaily.com/release...0113120656.htm

[Montanan]

On Saturday afternoon Eastern U.S. time, typhoon Surigae, which churned ominously close to the Philippines, had 190-mph winds after a bout of extremely rapid intensification, becoming the strongest typhoon, cyclone or hurricane ever observed in the month of April.

In fact, such a feat has never occurred in January, February, March or May, either.

Slew of rapidly intensifying hurricanes portends trouble in a warming world
According to Jeff Masters, a meteorologist for Yale Climate Connections, only four tropical cyclones reliably measured worldwide have featured higher wind speeds.

. . .

https://www.msn.com/en-us/weather/to...?ocid=msedgntp

[Reefmagnet]

Originally Posted by Montanan

On Saturday afternoon Eastern U.S. time, typhoon Surigae, which churned ominously close to the Philippines, had 190-mph winds after a bout of extremely rapid intensification, becoming the strongest typhoon, cyclone or hurricane ever observed in the month of April.

In fact, such a feat has never occurred in January, February, March or May, either.

Slew of rapidly intensifying hurricanes portends trouble in a warming world
According to Jeff Masters, a meteorologist for Yale Climate Connections, only four tropical cyclones reliably measured worldwide have featured higher wind speeds.

. . .

https://www.msn.com/en-us/weather/to...?ocid=msedgntp

I blame satellites.

[Tin Tin]

Originally Posted by Reefmagnet

I blame satellites.

Yep, it is only recently that they have been interpolating wind speeds (not physically measuring them) from satellite imaging, so unless there was a ship out there, with a reliable anemometer who would know what the wind speeds were 50 - 100+ years ago.


Climate gurus are now analyzing satellite data to point out and "name " storms that meet the now lower bar of being able to name one when in fact they are no stronger than a gale. They often drop out a day or so later. This is not to say the info is not useful to any vessels in the vicinity, but when the Weather Chanel makes its money from headlining such things (including now naming winter storms in the US) you have to wonder.

[GordMay]

“Tropical Cyclones and Climate Change Assessment: Part I: Detection and Attribution” ~ by Thomas Knutson et al

"... A number of specific published conclusions (case studies) about possible detectable anthropogenic influence on TCs were assessed using the conventional approach of preferentially avoiding type I errors (i.e., overstating anthropogenic influence or detection). We conclude there is at least low to medium confidence that the observed poleward migration of the latitude of maximum intensity in the western North Pacific is detectable, or highly unusual compared to expected natural variability. Opinion on the author team was divided on whether any observed TC changes demonstrate discernible anthropogenic influence, or whether any other observed changes represent detectable changes. The issue was then reframed by assessing evidence for detectable anthropogenic influence while seeking to reduce the chance of type II errors (i.e., missing or understating anthropogenic influence or detection). For this purpose, we used a much weaker “balance of evidence” criterion for assessment. This leads to a number of more speculative TC detection and/or attribution statements, which we recognize have substantial potential for being false alarms (i.e., overstating anthropogenic influence or detection) but which may be useful for risk assessment. Several examples of these alternative statements, derived using this approach, are presented in the report ..."
Report ➥ https://journals.ametsoc.org/view/jo...-18-0189.1.xml

In the northwest Pacific basin, there is emerging evidence for a detectable poleward shift in the latitude of maximum intensity of tropical cyclones, with a tentative link to anthropogenic warming.
“Past and Projected Changes in Western North Pacific Tropical Cyclone Exposure” ~ by James P. Kossin, Kerry A. Emanuel, and Suzana J. Camargo
➥ https://journals.ametsoc.org/view/jo...-16-0076.1.xml

[GordMay]

According to NASA’s Geophysical Fluid Dynamics Laboratory [GFDL]:
➥ https://www.gfdl.noaa.gov/global-war...nd-hurricanes/


A new study finds an increase in the fraction of tropical cyclones reaching at least Category 3 intensity, both globally and in the Atlantic basin, over the past four decades. These observed changes have not been compared with modeled responses to historical anthropogenic forcing, or to modeled natural variability; they have not been confidently attributed to anthropogenic forcing.
“Global increase in major tropical cyclone exceedance probability over the past four decades” ~ by James P. Kossin et al
➥ https://www.pnas.org/content/117/22/11975

A study of rapid intensification of hurricanes finds that the observed increase in an Atlantic rapid intensification metric (1982-2009) is highly unusual, compared to one climate model’s simulation of internal multidecadal climate variability, and is consistent in sign with that model’s expected long-term response to anthropogenic forcing.
“Recent increases in tropical cyclone intensification rates” ~ by Kieran T. Bhatia et al
➥ https://www.nature.com/articles/s414...5FuPgxOg%3D%3D

There is increasing evidence from modeling studies at GFDL/NOAA, and the UK Met Office/Hadley Centre (UKMO), that the increase in tropical storm frequency in the Atlantic basin, since the 1970s, has been, at least partly, driven by decreases in aerosols, from human activity, and volcanic forcing. Natural variability may also have contributed to recent changes.

The recent GFDL and UKMO studies do not imply that the increase in Atlantic tropical storm frequency, since the 1970s, will continue into the future: these same models project future decreases in Atlantic tropical storm frequency, in response to increasing greenhouse gas concentrations.
“Detected climatic change in global distribution of tropical cyclones” ~ by Hiroyuki Murakami et al
➥ https://www.pnas.org/content/117/20/10706
“Anthropogenic aerosol forcing of Atlantic tropical storms” ~ by N. J. Dunstone et al
➥ https://www.nature.com/articles/ngeo1854
“The role of Atlantic overturning circulation in the recent decline of Atlantic major hurricane frequency” ~ by Xiaoqin Yan, Rong Zhang & Thomas R. Knutson
➥ https://www.nature.com/articles/s41467-017-01377-8

There is evidence for a slowing of tropical cyclone propagation speeds over the continental U.S. over the past century, but these observed changes have not yet been confidently linked to anthropogenic climate change.

In summary, it is premature to conclude, with high confidence, that increasing atmospheric greenhouse gas concentrations, from human activities, have had a detectable impact on Atlantic basin hurricane activity, although increasing greenhouse gases are strongly linked to global warming.

Some possible human influences, on tropical cyclones, are summarized above. Human activities may have already caused other changes, in tropical cyclone activity, that are not yet detectable, due to the small magnitude of these changes, compared to estimated natural variability, or due to observational limitations.

[GordMay]

"Climate change is probably increasing the intensity of tropical cyclones” ~ by Thomas R. Knutson et al

Climate change is probably fuelling more powerful tropical cyclones, while flooding by tropical cyclones is amplified by rising sea level.
This ‘ScienceBrief Review’ examines the link between climate change and tropical cyclones (TCs, including tropical storms, hurricanes, and typhoons). It synthesises findings from more than 90 peer−reviewed scientific articles, gathered using ‘ScienceBrief’.

➥ https://news.sciencebrief.org/cyclones-mar2021/
➥ https://sciencebrief.org/uploads/rev...ES_Mar2021.pdf

[Exile]

Originally Posted by GordMay

According to NASA’s Geophysical Fluid Dynamics Laboratory [GFDL]:
➥ https://www.gfdl.noaa.gov/global-war...nd-hurricanes/


A new study finds an increase in the fraction of tropical cyclones reaching at least Category 3 intensity, both globally and in the Atlantic basin, over the past four decades. These observed changes have not been compared with modeled responses to historical anthropogenic forcing, or to modeled natural variability; they have not been confidently attributed to anthropogenic forcing.
“Global increase in major tropical cyclone exceedance probability over the past four decades” ~ by James P. Kossin et al
➥ https://www.pnas.org/content/117/22/11975

A study of rapid intensification of hurricanes finds that the observed increase in an Atlantic rapid intensification metric (1982-2009) is highly unusual, compared to one climate model’s simulation of internal multidecadal climate variability, and is consistent in sign with that model’s expected long-term response to anthropogenic forcing.
“Recent increases in tropical cyclone intensification rates” ~ by Kieran T. Bhatia et al
➥ https://www.nature.com/articles/s414...5FuPgxOg%3D%3D

There is increasing evidence from modeling studies at GFDL/NOAA, and the UK Met Office/Hadley Centre (UKMO), that the increase in tropical storm frequency in the Atlantic basin, since the 1970s, has been, at least partly, driven by decreases in aerosols, from human activity, and volcanic forcing. Natural variability may also have contributed to recent changes.

The recent GFDL and UKMO studies do not imply that the increase in Atlantic tropical storm frequency, since the 1970s, will continue into the future: these same models project future decreases in Atlantic tropical storm frequency, in response to increasing greenhouse gas concentrations.
“Detected climatic change in global distribution of tropical cyclones” ~ by Hiroyuki Murakami et al
➥ https://www.pnas.org/content/117/20/10706
“Anthropogenic aerosol forcing of Atlantic tropical storms” ~ by N. J. Dunstone et al
➥ https://www.nature.com/articles/ngeo1854
“The role of Atlantic overturning circulation in the recent decline of Atlantic major hurricane frequency” ~ by Xiaoqin Yan, Rong Zhang & Thomas R. Knutson
➥ https://www.nature.com/articles/s41467-017-01377-8

There is evidence for a slowing of tropical cyclone propagation speeds over the continental U.S. over the past century, but these observed changes have not yet been confidently linked to anthropogenic climate change.

In summary, it is premature to conclude, with high confidence, that increasing atmospheric greenhouse gas concentrations, from human activities, have had a detectable impact on Atlantic basin hurricane activity, although increasing greenhouse gases are strongly linked to global warming.

Some possible human influences, on tropical cyclones, are summarized above. Human activities may have already caused other changes, in tropical cyclone activity, that are not yet detectable, due to the small magnitude of these changes, compared to estimated natural variability, or due to observational limitations.

A rather illuminating contrast presented here, for those who choose to acknowledge it that is, between . . . shall we say . . . the actual "mathematics, statistics & science", versus the politicians & media (and those amongst us who believe those two entities are telling us the truth) when they proclaim a climate crisis "emergency."

[GordMay]

Originally Posted by Exile

A rather illuminating contrast presented here, for those who choose to acknowledge it that is, between . . . shall we say . . . the actual "mathematics, statistics & science", versus the politicians & media (and those amongst us who believe those two entities are telling us the truth) when they proclaim a climate crisis "emergency."

The studies, to which I linked, were really only examining the very narrow question of hurricane intensity & frequency, and their [so far] weak link to climate change.
None of them doubted, in any degree, that anthropogenic climate change is occurring, and unchecked, represents an 'emergency'.
You really should read the GFDL website, from which I culled them. It will inform your [mis]understanding.
➥ https://www.gfdl.noaa.gov/global-war...nd-hurricanes/

IMO: Those politicians, you so happily excoriate, have, mostly, been very slow to begin to recognise, and respond, halfheartedly to, our climate emergency.


I suppose your resonse is what I should expect, from some, in trying to present a balanced representation of nuanced scientific opinion.

[Exile]

Originally Posted by GordMay

The studies, to which I linked, were really only examining the very narrow question of hurricane intensity & frequency, and their [so far] weak link to climate change.
None of them doubted, in any degree, that anthropogenic climate change is occurring, and unchecked, represents an 'emergency'.
You really should read the GFDL website, from which I culled them. It will inform your [mis]understanding.
➥ https://www.gfdl.noaa.gov/global-war...nd-hurricanes/

IMO: Those politicians, you so happily excoriate, have, mostly, been very slow to begin to recognise, and respond, halfheartedly to, our climate emergency.


I suppose your resonse is what I should expect, from some, in trying to present a balanced representation of nuanced scientific opinion.

It's not about "nuanced" scientific opinion, but about how "settled" the scientific opinion is compared to what most people hear & read from politicians and the news media. There doesn't seem to be much dispute within the field of climate science itself that anthropogenic climate change exists, and that perhaps most climate scientists believe, as you say, it is "occurring." I've already acknowledged if not emphasized this in this very thread. But as you know as a follower of the science, this consensus is hardly uniform when it comes to the question of how much anthropogenic vs. natural forces are influencing the climate, and even less consistent when it comes to what we can or should do to counteract it.

My mistake if my post was too generalized, but what I intended to point out was the obvious scientific uncertainty over causation (based on the studies you posted) between AGW and the frequency and intensity of tropical storms, hurricanes & cyclones, and the characterization of these same (and other) events as a "crisis" and "emergency" to bolster the case for CC by politicians, media and uninformed people on internet forums. IOW, and in this specific case involving storms (the thread topic), the same science you cite simply doesn't support attribution of such recent or historic events to AGW, and even their future predictions based on modeling is far from the type of certainty we are constantly deluged with from patently non-scientific sources of information.

I just read the scientific article you referred me to here, although admittedly only skimmed it in the interest of time. In case I missed it, please tell us where it says, as you claim, that AGW, "if left unchecked, represents an 'emergency'." Certainly you can't mean an "emergency" from the topic of this thread that you started, at least not based on the scientific evidence you yourself presented. Rising seas? Coral reef bleaching and/or death? Forest fires? Droughts, floods, population movements? Environmental injustice?? Maybe or maybe not, but this wasn't what I was responding to. There's only so many times a citizenry can be frightened into achieving policy objectives before credibility becomes compromised.

[Pelagic]

For those of us who live in areas of seasonal Typhoons /Cyclones or Hurricanes
.....we have become far more aware of every disturbance that moves thru our area, due to the wonderful advances in weather tracking.

This then becomes "subjectively" an increase in events