'Hurricane Sandy: The next climate wake-up call?'

[donsutherland1]

Yes, that's the headline of a Politico story.

http://www.politico.com/news/stories/1012/82813.html?hp=l8

IMO, the headline and quotes in the story aimed at creating perceptions of a link to climate change do not amount to good journalism. It creates the impression that without climate change, the risk of such an event would be materially reduced.

Currently, the ability to tie climate change to tropical cyclone activity, not to mention tropical cyclone tracks, is very weak. A limited argument might be made concerning a contribution from the SSTAs along Sandy's path, but even that argument could be a stretch, as the impact of the SSTAs might be modest in the overall context of Sandy's evolution. Were baroclinic processes related to the interaction of Sandy and the trough to allow the system to conserve strength or even deepen, the role of the SSTAs might be further reduced. In addition, it is still difficult to determine to what extent the current SSTAs are a product of climate change and to what extent they are the product of natural variability.

Second, one is dealing with a severe block similar in magnitude to that which was present during the Hurricane #8 (1991) aka "the Perfect Storm." During the 10/28-11/4/1991 timeframe, the AO bottomed out at -3.044. Today's value was -3.130. That block played an important role in influencing that storm's track. The synoptic pattern will determine Sandy's future track and whether or not Sandy phases. In short, whatever the outcome with Sandy, it will be difficult to argue that such an outcome would have been significantly less likely absent climate change.

As noted in the past, I fully accept the science regarding climate change and the anthropogenic role driving climate change. However, this article goes far beyond what the actual science suggests. In doing so, it risks undermining the credibility of climate science among the general public, even as the scientific evidence for AGW is strong. In turn, public perceptions are critical to shaping public policy.

[SVT450R]

Well said Don tho sadly we know this will be hyped as do in part of climate change especially if the outcome is a direct impact on the east coast per being modeled by the Euro.

[Msalgado]

Great post, Don.

[Alpha5]

Agreed, Politico should stick to electoral college analysis.

[somethingfunny]

Considering as evidence that the vast majority of the analogs we have to compare this scenario to are from the 1800s, I will make an argument that I shouldn't even bother making to anybody who doesn't understand it already.

[HurricaneJosh]

I cannot stand when the mainstream/political journalists get onto this topic. Ugh. And I'm someone who absolutely believes in climate change.

[csnavywx]

Yes, that's the headline of a Politico story.

http://www.politico....2813.html?hp=l8

IMO, the headline and quotes in the story aimed at creating perceptions of a link to climate change do not amount to good journalism. It creates the impression that without climate change, the risk of such an event would be materially reduced.

Currently, the ability to tie climate change to tropical cyclone activity, not to mention tropical cyclone tracks, is very weak. A limited argument might be made concerning a contribution from the SSTAs along Sandy's path, but even that argument could be a stretch, as the impact of the SSTAs might be modest in the overall context of Sandy's evolution. Were baroclinic processes related to the interaction of Sandy and the trough to allow the system to conserve strength or even deepen, the role of the SSTAs might be further reduced. In addition, it is still difficult to determine to what extent the current SSTAs are a product of climate change and to what extent they are the product of natural variability.

Second, one is dealing with a severe block similar in magnitude to that which was present during the Hurricane #8 (1991) aka "the Perfect Storm." During the 10/28-11/4/1991 timeframe, the AO bottomed out at -3.044. Today's value was -3.130. That block played an important role in influencing that storm's track. The synoptic pattern will determine Sandy's future track and whether or not Sandy phases. In short, whatever the outcome with Sandy, it will be difficult to argue that such an outcome would have been significantly less likely absent climate change.

As noted in the past, I fully accept the science regarding climate change and the anthropogenic role driving climate change. However, this article goes far beyond what the actual science suggests. In doing so, it risks undermining the credibility of climate science among the general public, even as the scientific evidence for AGW is strong. In turn, public perceptions are critical to shaping public policy.

Yep, the responsible thing to do would be to wait until after the storm (which still isn't even a guaranteed thing as this point) and (at the very least) an attribution study before declaring this. It's fine to speculate, but it should be labeled as such.

[csnavywx]

I cannot stand when the mainstream/political journalists get onto this topic. Ugh. And I'm someone who absolutely believes in climate change.

It's this type of mishandling and miscommunication by the media that hurts the science more than it helps.

[aslkahuna]

The media feeds the skepticism with outrageous stories as this. Their intention is surely the opposite but their efforts usually backfire. The media should stick to stories about Lindsay Lohan, etc. since any attempt on their part to properly inform the public on issues such as climate change are doomed to failure.

Steve

[Snow_Miser]

More unsubstantiated alarmism from the mainstream media. Nothing new to see here.

[TerryM]

Some at least find the storm track to be an oddity - and isn't increasingly unusual weather what has been predicted with increasing global warming?

"Wow... what an extraordinarily unusual scenario."

"spectacularly unusual"

"so bizarrely unusual that I can't think of another event like it. "

http://www.wunderground.com/blog/bnorcross/comment.html?entrynum=16

[skierinvermont]

Some at least find the storm track to be an oddity - and isn't increasingly unusual weather what has been predicted with increasing global warming?

"Wow... what an extraordinarily unusual scenario."

"spectacularly unusual"

"so bizarrely unusual that I can't think of another event like it. "

http://www.wundergro...tml?entrynum=16

It's not THAT weird. Negative trough and blocking. There are analogs to this storm. Not many, but some. And many if not most are from a much colder climate.

Storms the 1991 Perfect Storm, the Hurricane of 1938, this storm (if it comes to fruition), and others like them may become slightly more or less common in a warmer climate. If I had to guess, I'd say more common. But we really don't know. And even if we did know that storms like this will become 10% more common in a warmer climate, it would not be grounds for claiming this storm is a 'climate wake up call.'

[tacoman25]

Some at least find the storm track to be an oddity - and isn't increasingly unusual weather what has been predicted with increasing global warming?

"Wow... what an extraordinarily unusual scenario."

"spectacularly unusual"

"so bizarrely unusual that I can't think of another event like it. "

http://www.wundergro...tml?entrynum=16

It hasn't even happened yet. At this point it's a non-event.

But by all means, feed the hype/alarmism!

[skierinvermont]

It hasn't even happened yet. At this point it's a non-event.

But by all means, feed the hype/alarmism!

I think odds are at least 50% this point for a sub 960mb landfall between NC and ME... no need to hype that.

[tacoman25]

I think odds are at least 50% this point for a sub 960mb landfall between NC and ME... no need to hype that.

Not the event itself, IF it happens like that, but rather Terry's not so novel approach of hyping anything "unusual" as due to AGW. Especially if its destructive and grabs lots of headlines.

But we must remember who pays our trolls.

[Vergent]

The storm track is well within the historical norm. The article title is at odds with the text which does not really address climate change. I think the title is ironic. In a presidential campaign where AGW and climate change have been non-issues, weather has disrupted one convention and now might be an issue a week before the election. Climate change is the 800lb gorilla in the room.

edit

[tamarack]

When I first read the thread title and its starter, my initial thought was, Oh no, Don's gone over to the alarmist-media claque. After reading the OP, it became "O ye of little faith", aimed at myself.

Excellent post, Don, as usual.

[PhillipS]

It might helpful to look at some of the metrics for the 2012 Atlantic Hurricane Season and how it compares to previous years. Wikipedia has a good article on ACE and the article contains an interactive table of hurricane metrics.

Regarding ACE, the 2012 season has a current value of 110,which will rise somewhat with Hurricane Sandy and TS Tony still active. But that value puts 2012 in the middle of the rankings and is no where near the record of 248 set in 2005. Of the ten highest years, three (2003, 2004, 2005) have occurred since 2000.

On the number of named tropical storms, 2012 is currently at 19 which puts it in a four-way tie for 2nd place on the all-time list. Of the ten highest years, eight (2000, 2003, 2004, 2005, 2008, 2010, 2011, 2012) have occurred since 2000. Given that 2001 and 2007 are ranked 11th and 12th, it does appear that we are experiencing more tropical storms in recent years than in the distant past.

On the number of hurricanes, 2012 has had 10 so far which puts it in a tie for 6th place. Of the ten highest years, five (2001, 2004, 2005, 2010, 2012) have occurred since 2000.

And on the number of major hurricanes (Cat 3 or above), 2012 has had only 1 so far which, of course, puts it well down the list. Of the ten highest years, 3 (2004, 2005, 2010) occurred since 2000.

My off-the-cuff opinion is that the numbers indicate an increase in the number of TSs and weak hurricanes (due to higher SSTs possibly?), and a decrease in the number of major hurricanes (due to higher wind shear impeding storm growth?)

[skierinvermont]

It might helpful to look at some of the metrics for the 2012 Atlantic Hurricane Season and how it compares to previous years. Wikipedia has a good article on ACE and the article contains an interactive table of hurricane metrics.

Regarding ACE, the 2012 season has a current value of 110,which will rise somewhat with Hurricane Sandy and TS Tony still active. But that value puts 2012 in the middle of the rankings and is no where near the record of 248 set in 2005. Of the ten highest years, three (2003, 2004, 2005) have occurred since 2000.

On the number of named tropical storms, 2012 is currently at 19 which puts it in a four-way tie for 2nd place on the all-time list. Of the ten highest years, eight (2000, 2003, 2004, 2005, 2008, 2010, 2011, 2012) have occurred since 2000. Given that 2001 and 2007 are ranked 11th and 12th, it does appear that we are experiencing more tropical storms in recent years than in the distant past.

On the number of hurricanes, 2012 has had 10 so far which puts it in a tie for 6th place. Of the ten highest years, five (2001, 2004, 2005, 2010, 2012) have occurred since 2000.

And on the number of major hurricanes (Cat 3 or above), 2012 has had only 1 so far which, of course, puts it well down the list. Of the ten highest years, 3 (2004, 2005, 2010) occurred since 2000.

My off-the-cuff opinion is that the numbers indicate an increase in the number of TSs and weak hurricanes (due to higher SSTs possibly?), and a decrease in the number of major hurricanes (due to higher wind shear impeding storm growth?)

SS is too small to conclude anything esp. given the +AMO. Also your conclusions are the opposite of most experts at this point.

[tacoman25]

It might helpful to look at some of the metrics for the 2012 Atlantic Hurricane Season and how it compares to previous years. Wikipedia has a good article on ACE and the article contains an interactive table of hurricane metrics.

Regarding ACE, the 2012 season has a current value of 110,which will rise somewhat with Hurricane Sandy and TS Tony still active. But that value puts 2012 in the middle of the rankings and is no where near the record of 248 set in 2005. Of the ten highest years, three (2003, 2004, 2005) have occurred since 2000.

On the number of named tropical storms, 2012 is currently at 19 which puts it in a four-way tie for 2nd place on the all-time list. Of the ten highest years, eight (2000, 2003, 2004, 2005, 2008, 2010, 2011, 2012) have occurred since 2000. Given that 2001 and 2007 are ranked 11th and 12th, it does appear that we are experiencing more tropical storms in recent years than in the distant past.

On the number of hurricanes, 2012 has had 10 so far which puts it in a tie for 6th place. Of the ten highest years, five (2001, 2004, 2005, 2010, 2012) have occurred since 2000.

And on the number of major hurricanes (Cat 3 or above), 2012 has had only 1 so far which, of course, puts it well down the list. Of the ten highest years, 3 (2004, 2005, 2010) occurred since 2000.

My off-the-cuff opinion is that the numbers indicate an increase in the number of TSs and weak hurricanes (due to higher SSTs possibly?), and a decrease in the number of major hurricanes (due to higher wind shear impeding storm growth?)

9/10 lowest ACE years occurred in the -AMO phase. Probably a significant factor here.

[PhillipS]

SS is too small to conclude anything esp. given the +AMO. Also your conclusions are the opposite of most experts at this point.

Well, it's a 62 year sample size (since 1950), and I don't have any reason to doubt the accuracy of the data. I just gave my opinion - if climatologists have published studies with opposite conclusions I would appreciate links to their research so I can learn more.

[ORH_wxman]

Well, it's a 62 year sample size (since 1950), and I don't have any reason to doubt the accuracy of the data. I just gave my opinion - if climatologists have published studies with opposite conclusions I would appreciate links to their research so I can learn more.

This is a good paper...with plenty of others cited in here as well:

http://www.nhc.noaa.gov/pdf/landsea-et-al-jclim2010.pdf

[tacoman25]

The fact is, no one really knows for sure how AGW might affect tropical storm development in the future, and there is no discernible trend that correlates with AGW now. There is a much stronger correlation to the AMO, at least for the Atlantic. And a weaker correlation to the PDO for the Pacific.

[skierinvermont]

Well I was more referring to how models predict fewer TCs with AGW but higher average intensity (this is a low confidence prediction)... the opposite of what Phillip's stats show. But yeah also we can't even be sure that the stats are right.

[tacoman25]

Well I was more referring to how models predict fewer TCs with AGW but higher average intensity (this is a low confidence prediction)... the opposite of what Phillip's stats show. But yeah also we can't even be sure that the stats are right.

Agreed, that is kind of the "consensus" outlook at the moment, but as you said it's low confidence and to this point there is no evidence it is occurring.

[PhillipS]

This is a good paper...with plenty of others cited in here as well:

http://www.nhc.noaa....l-jclim2010.pdf

I"ve read that paper before, and while I consider it interesting, I can't say I think it's good. Their methodology seems very shaky. Their hypothesis is that observational limitations in the19th and early 20th centuries missed many tropical cyclones (TCs), particularly short-lived ones, and the apparent trend of increasing number of TCs is an artifact of today's better data gathering platforms.

What I have trouble with is that they try to adjust for missed historic TCs by using estimates, and these estimates are derived from recent TC observations and are exactly the right magnitude to eliminate the observed trend. When I read that my BS detector started flashing. It is circular reasoning to use estimates derived from a trend, adjust the observational data with those estimates, and then claim the trend is eliminated. Well, duh! With their approach, any trend of any magnitude and sign could be eliminated from any dataset! I think a better approach would have been to use their estimates of missed TCs to increase the uncertainty bars of the early record.

I certainly agree that today's technology of satellite observations and Hurricane Hunter aircraft do a better job of detecting and characterizing TCs than the limited ship-based observations of the early 20th century and earlier. But if the observed increase in TCs was purely an artifact of better sensors I would expect to see a step increase in the number of TC at the time the sensors went on-line - instead we see a roughly linear increase. How is a linear increase explained by better sensors?

The time period (1959 to present) used in the wikipedia article and which I used in my earlier post is a pretty robust one, in my opinion. It spans the entire satelite era and includes the post-WWII observations of the 53d Weather Reconnaissance Squadron (the Hurricane Hunters) which began operations in 1945. We've had good data collection for that entire period. And with a span of 62 years it is more than twice the 30 year minimum for determining climate trends.

Other posters on this thread have pointed out that models have predicted a decrease in the number of Atlantic TCs. Okay. But given a choice between estimates (Landsea), model predictions and observational data - which has the greatest credibility? For me it is unquestionably the observational data - the data record is what it is. I'm sure that some on this forum will deny the validity of the data and prefer estimates or model runs instead, If they can explain the observed data in terms of their favored model that's fine, but so far all I've seen is just rhetorical handwaving that the observational data isn't important - which is an attitude I find to be pretty unscientific.

Whatever one believes it is still a matter of record that for the Atlantic hurricane seasons since 1950, 10 of the top 12 years of high TC activity (# of named storms) have occurred since the year 2000. Put another way, the most recent 21% of the period 1950 to today is responsible for 83% of the hurricane seasons with the highest TC activity.

[skierinvermont]

I"ve read that paper before, and while I consider it interesting, I can't say I think it's good. Their methodology seems very shaky. Their hypothesis is that observational limitations in the19th and early 20th centuries missed many tropical cyclones (TCs), particularly short-lived ones, and the apparent trend of increasing number of TCs is an artifact of today's better data gathering platforms.

What I have trouble with is that they try to adjust for missed historic TCs by using estimates, and these estimates are derived from recent TC observations and are exactly the right magnitude to eliminate the observed trend. When I read that my BS detector started flashing. It is circular reasoning to use estimates derived from a trend, adjust the observational data with those estimates, and then claim the trend is eliminated. Well, duh! With their approach, any trend of any magnitude and sign could be eliminated from any dataset! I think a better approach would have been to use their estimates of missed TCs to increase the uncertainty bars of the early record.

I certainly agree that today's technology of satellite observations and Hurricane Hunter aircraft do a better job of detecting and characterizing TCs than the limited ship-based observations of the early 20th century and earlier. But if the observed increase in TCs was purely an artifact of better sensors I would expect to see a step increase in the number of TC at the time the sensors went on-line - instead we see a roughly linear increase. How is a linear increase explained by better sensors?

The time period (1959 to present) used in the wikipedia article and which I used in my earlier post is a pretty robust one, in my opinion. It spans the entire satelite era and includes the post-WWII observations of the 53d Weather Reconnaissance Squadron (the Hurricane Hunters) which began operations in 1945. We've had good data collection for that entire period. And with a span of 62 years it is more than twice the 30 year minimum for determining climate trends.

Other posters on this thread have pointed out that models have predicted a decrease in the number of Atlantic TCs. Okay. But given a choice between estimates (Landsea), model predictions and observational data - which has the greatest credibility? For me it is unquestionably the observational data - the data record is what it is. I'm sure that some on this forum will deny the validity of the data and prefer estimates or model runs instead, If they can explain the observed data in terms of their favored model that's fine, but so far all I've seen is just rhetorical handwaving that the observational data isn't important - which is an attitude I find to be pretty unscientific.

Whatever one believes it is still a matter of record that for the Atlantic hurricane seasons since 1950, 10 of the top 12 years of high TC activity (# of named storms) have occurred since the year 2000. Put another way, the most recent 21% of the period 1950 to today is responsible for 83% of the hurricane seasons with the highest TC activity.

Your description of the Landsea paper is incorrect.

1) The "adjustment" is not derived from the recent period. They simply subtract short-lived TCs from the record. This removes the majority of the trend in TC counts. This does not even qualify as an adjustment. All they are doing is presenting the fact that HURDAT, which is a meticulously compiled record, shows very little trend in medium to long duration TCs. They then use VK08, which is a previously developed method for estimating sampling error, to make one small adjustment primarily to the late 19th century and very early 20th century. The lower ship traffic during this period would undoubtedly lead to undersampling. I would not say that the resulting estimate of medium to long duration TCs is perfect, but I would say it is very good.

2) This was published in the Journal of Climate and has been widely cited in many other major papers. I would be very cautious about disregarding its conclusions.

3) You suggest that we should see a jump in the data when new detection came on line. This is not the case. New detection did not just "come on line." By the 1950s TCs were pretty well sampled by ship traffic. What occurred was a gradual increase in sampling as ship traffic increased from 1880 to the 1950s. Then satellites started coming online in the 1960s (I think) and that would have provided one final increase as we were able to detect very small/short/weak TCs. But there would never have been a large jump. It was a more gradual process culminating in satellite technology. Also I'd guess satellite technology/coverage has improved over the years.

4) You say 1959-present is a long enough period. I disagree. You are looking at 30 years of -AMO and then 20 years of +AMO, and the AMO has a strong impact on TC count. It's clear there was more TC activity in the 30s 40s and 50s than the 60s 70s and 80s, even ignoring the fact that the 30s 40s and 50s were undersampled by shipping data.

5) You offer us a choice between "estimates, models, and observational data" and say you pick "observational data." Are you aware that GISS and HadCRUT and all other surface temperature records are "merely" estimates and not actually observational data? The observational data has undergone far more adjustment than the Landsea data has. So would you tell us to ignore GISS, BEST etc. and look only at the un-adjusted data which shows that the earth has been cooling for the last 100+ years? The fact is sometimes adjustments are necessary. The fact that your BS detector is going off I would suggest says more about you than the quality of the paper...

6) It is fairly widely accepted that TC count will go down with AGW and intensity up. I previously said this was a "low confidence" prediction but it's probably more of a medium confidence prediction. I've come across many papers on the subject over the last 5 years. Here's one such paper that was published fairly recently and provides a review of current literature. Current literature suggests a 6-34% decrease in TC frequency and a 2-11% increase in intensity by 2100.

http://www.nature.co...ll/ngeo779.html

[superjames1992]

Some at least find the storm track to be an oddity - and isn't increasingly unusual weather what has been predicted with increasing global warming?

"Wow... what an extraordinarily unusual scenario."

"spectacularly unusual"

"so bizarrely unusual that I can't think of another event like it. "

http://www.wundergro...tml?entrynum=16

Tying one storm to widespread climate fluctuations is ridiculous.

This is a weather phenomenon, not climate. If these sorts of storms increase in the coming years, then there may be a point to be made, but there isn't really any evidence of that yet.

All these stories do is provide deniers ammunition for disregarding real climate change science, which is unfortunate.

[TerryM]

Tying one storm to widespread climate fluctuations is ridiculous.

This is a weather phenomenon, not climate. If these sorts of storms increase in the coming years, then there may be a point to be made, but there isn't really any evidence of that yet.

All these stories do is provide deniers ammunition for disregarding real climate change science, which is unfortunate.

If you think so poorly of Bryan Norcross's statements, perhaps you should let him know.

I do recall Hansen and others saying we were in for some very odd weather as global warming progressed. I'm not a follower of extreme weather events, but when Weather Underground resorted to such flights of hyperbola in describing just how unusual Sandy is, the connection seemed obvious.

If no one extreme event can be tied to AGW, but a series of extreme events can. I'd submit that the last few years has been nothing but a series of strange winters, summers, storms and droughts. One could argue that any one of them would have occurred naturally, but the odds on having so many records being set in such a short period of time indicates, at least to me, that the dice have been loaded and we're no longer playing the same game we were even 20 years ago.

You're undoubtedly correct that this particular storm can't be directly linked to global warming, but since Sandy's unusual track is unique because of it's interaction with the polar jet stream, and the jet stream is undoubtedly affected by the unusual condition of Arctic ice, I don't think making a connection is going too far out on a limb.

You mention waiting until more storms occur before making your point, if this storm follows the track predicted we'll have had two hurricanes threatening NYC in two years - when was the last time this happened - and how many consecutive years would you require before you found it prudent to draw an inference.

I can't imagine that too many of the fake skeptics will find solace in my musings, but to suppress suppositions for fear that they will be misused by others would simply be to concede the field to the enemy without a fight. Just as the Texas drought convinced many of the reality of climate change, this storm, if it proves to be as unusual as is predicted will convince many more.

Terry

[dabize]

If you think so poorly of Bryan Norcross's statements, perhaps you should let him know.

I do recall Hansen and others saying we were in for some very odd weather as global warming progressed. I'm not a follower of extreme weather events, but when Weather Underground resorted to such flights of hyperbola in describing just how unusual Sandy is, the connection seemed obvious.

If no one extreme event can be tied to AGW, but a series of extreme events can. I'd submit that the last few years has been nothing but a series of strange winters, summers, storms and droughts. One could argue that any one of them would have occurred naturally, but the odds on having so many records being set in such a short period of time indicates, at least to me, that the dice have been loaded and we're no longer playing the same game we were even 20 years ago.

You're undoubtedly correct that this particular storm can't be directly linked to global warming, but since Sandy's unusual track is unique because of it's interaction with the polar jet stream, and the jet stream is undoubtedly affected by the unusual condition of Arctic ice, I don't think making a connection is going too far out on a limb.

You mention waiting until more storms occur before making your point, if this storm follows the track predicted we'll have had two hurricanes threatening NYC in two years - when was the last time this happened - and how many consecutive years would you require before you found it prudent to draw an inference.

I can't imagine that too many of the fake skeptics will find solace in my musings, but to suppress suppositions for fear that they will be misused by others would simply be to concede the field to the enemy without a fight. Just as the Texas drought convinced many of the reality of climate change, this storm, if it proves to be as unusual as is predicted will convince many more.

Terry

Terry, didn't you get the message?

AGW is NEVER a factor in any weather event, by definition.

They'll be saying this about the Apocalypse when it hits on Judgment Day........