Climate of the Future

[PottercountyWXobserver]

A big storm near bermuda can really destroy the subtropical ridge. It happens most active years but the ridge can build back, activity just needs to quiet down for a week.

I'm begining to think, but don't laugh. That AGW is causing more lower end intensity type storms because of greater shear, but it is also causing more storms to form in the atlantic which are fishing out more so than climatology would argue for. The reason storms are fishing out more than climatology would argue for is because storms are becoming stronger once exiting off the african coast more than they would before. This is turn is causing the subtropical ridge to be attacked by mulitple events within the tropical storm year causing the ridge to have a hard time building back in, which is possibly the answer to why the east coast in general has seen a lack of any major threats in the last several years. I could be totally wrong in my thinking, but I just thought I would throw it out there.

This would fit into the more storms with lower end intensity however, greater highend storms when conditions are perfect.

[Ed Lizard]

I'm begining to think, but don't laugh. That AGW is causing more lower end intensity type storms because of greater shear, but it is also causing more storms to form in the atlantic which are fishing out more so than climatology would argue for. The reason storms are fishing out more than climatology would argue for is because storms are becoming stronger once exiting off the african coast more than they would before. This is turn is causing the subtropical ridge to be attacked by mulitple events within the tropical storm year causing the ridge to have a hard time building back in, which is possibly the answer to why the east coast in general has seen a lack of any major threats in the last several years. I could be totally wrong in my thinking, but I just thought I would throw it out there.

This would fit into the more storms with lower end intensity however, greater highend storms when conditions are perfect.

AGW explains the difference between 2004 and 2005, and even 2008, and 7 years later 2011 and 2012? Not disputing or agreeing w/ AGW, just that there'd be a flipped light switch in under a decade.

[PottercountyWXobserver]

AGW explains the difference between 2004 and 2005, and even 2008, and 7 years later 2011 and 2012? Not disputing or agreeing w/ AGW, just that there'd be a flipped light switch in under a decade.

No there is def internal variations with enso, teleconnections in general, but AGW will show trends in all weather events. Afterall climate is just the average of weather periods anyways. In a warming world, storms are going to have the tendency to become stronger once exiting off the coast of Africa, and this in tune will increase the likelyhood of storms fishing earlier than they once would before. Granted, storms can still become weak and stay weak earlier in the season with SSTs still cooler and SAL that still affects storms, thus I believe the greater likelyhood of American threats will become more favorable in the ealier months as waves will tend to stay weaker and develop much closer to home. Later in the season as factors become favorable for stronger systems, AGW will increase the likelyhood these factors increase the chances of fish storms. We all know early developing systems have a greater chance of fishining anyways as these storms feel the perturbations in the westerlies, well AGW will cause these chance to increase in earlier developing systems.

[thewxmann]

I'm begining to think, but don't laugh. That AGW is causing more lower end intensity type storms because of greater shear, but it is also causing more storms to form in the atlantic which are fishing out more so than climatology would argue for. The reason storms are fishing out more than climatology would argue for is because storms are becoming stronger once exiting off the african coast more than they would before. This is turn is causing the subtropical ridge to be attacked by mulitple events within the tropical storm year causing the ridge to have a hard time building back in, which is possibly the answer to why the east coast in general has seen a lack of any major threats in the last several years. I could be totally wrong in my thinking, but I just thought I would throw it out there.

This would fit into the more storms with lower end intensity however, greater highend storms when conditions are perfect.

It's hard to correlate cyclone track with AGW. And storms aren't "becoming stronger" exiting off the African coast. If anything, though we've had an abundance of nice seedling waves due to (what is probably) below-average SLP's in the Sahel region, it hasn't translated into juicy CV storms. Furthermore, unless the next 20-50 years remain abnormally fishy, the best we can do is to just say it's random.

I do think, however, that AGW could be contributing to a decrease in either number or intensity of TC's -- through all basins. From what I recall global ACE has been below average for over a decade now. But again without a larger sample set it'd be hard to prove.

[PottercountyWXobserver]

It's hard to correlate cyclone track with AGW. And storms aren't "becoming stronger" exiting off the African coast. If anything, though we've had an abundance of nice seedling waves due to (what is probably) below-average SLP's in the Sahel region, it hasn't translated into juicy CV storms. Furthermore, unless the next 20-50 years remain abnormally fishy, the best we can do is to just say it's random.

I do think, however, that AGW has been contributing to a decrease in either number or intensity of TC's -- through all basins. From what I recall global ACE has been below average for over a decade now.

When I mean stronger, I mean that in the relative sense. Instead of seeing depressions and very low end TS traversing the Atlantic, we are seeing waves to have a greater tendency to become higher end TS and weak garbage type Cat 1-2 storms quicker than they otherwise would. I never said very juicy CV storms, because I don't think that is happening at a correlating pace quite yet. The region maybe producing below average SLP but when they do form, they are forming "stronger" than they would otherwise. I don't think this abnormally fishy track is just random, I fully believe it is correlated greatly with AGW. It is hard to correlate cyclone tracks with AGW, but I believe it is becoming quite noticable and people are begining to notice the abnormal tracks. You are right in that most systems are having a "lower overall intensity" do to lower ACE values, but however when systems due have perfect conditions, we will have greater probability to have stronger systems to form even record intensity systems, and we have already witnessed this happening.

[Juliancolton]

When I mean stronger, I mean that in the relative sense. Instead of seeing depressions and very low end TS traversing the Atlantic, we are seeing waves to have a greater tendency to become higher end TS and weak garbage type Cat 1-2 storms quicker than they otherwise would. I never said very juicy CV storms, because I don't think that is happening at a correlating pace quite yet. The region maybe producing below average SLP but when they do form, they are forming "stronger" than they would otherwise. I don't think this abnormally fishy track is just random, I fully believe it is correlated greatly with AGW. It is hard to correlate cyclone tracks with AGW, but I believe it is becoming quite noticable and people are begining to notice the abnormal tracks. You are right in that most systems are having a "lower overall intensity" do to lower ACE values, but however when systems due have perfect conditions, we will have greater probability to have stronger systems to form even record intensity systems, and we have already witnessed this happening.

There's nothing really abnormal about recent storm tracks. Tropical cyclones, by their nature, want to try to get as close to the pole as they can to fulfil their purpose of distributing heat energy across the globe. It takes specific basin-wide patterns to get a long-tracking storm far enough west to make landfall, and I can't recall any storm where I would expect a US landfall and the storm somehow—by no identifiable factor other than vague global warming—managed to avoid land. Can you think of any?

[thewxmann]

There's nothing really abnormal about recent storm tracks. Tropical cyclones, by their nature, want to try to get as close to the pole as they can to fulfil their purpose of distributing heat energy across the globe. It takes specific basin-wide patterns to get a long-tracking storm far enough west to make landfall, and I can't recall any storm where I would expect a US landfall and the storm somehow—by no identifiable factor other than vague global warming—managed to avoid land. Can you think of any?

Being a bit anal here, but just to clarify -- tropical cyclones have no "will" of their own, nor a "purpose" so to speak. Their tendency to move northward is due to the Beta effect -- variation of Coriolis force with latitude. That this is able to help modulate heat exchange between the poles and the equator is merely coincidence.

[PottercountyWXobserver]

Being a bit anal here, but just to clarify -- tropical cyclones have no "will" of their own, nor a "purpose" so to speak. Their tendency to move northward is due to the Beta effect -- variation of Coriolis force with latitude. That this is able to help modulate heat exchange between the poles and the equator is merely coincidence.

This is true, but the stronger the systems, the more likely they are to be influenced from the westerlies if pertubations in the jetstream happen and thus a more nothern and fishy track.

[thewxmann]

When I mean stronger, I mean that in the relative sense. Instead of seeing depressions and very low end TS traversing the Atlantic, we are seeing waves to have a greater tendency to become higher end TS and weak garbage type Cat 1-2 storms quicker than they otherwise would. I never said very juicy CV storms, because I don't think that is happening at a correlating pace quite yet. The region maybe producing below average SLP but when they do form, they are forming "stronger" than they would otherwise. I don't think this abnormally fishy track is just random, I fully believe it is correlated greatly with AGW. It is hard to correlate cyclone tracks with AGW, but I believe it is becoming quite noticable and people are begining to notice the abnormal tracks. You are right in that most systems are having a "lower overall intensity" do to lower ACE values, but however when systems due have perfect conditions, we will have greater probability to have stronger systems to form even record intensity systems, and we have already witnessed this happening.

No... each storm is a function of its own environment. You can't say that AGW is magically transforming garbage into Cat 1/2. And given the SAL/dry air/shear/etc.etc.etc. issues we've had with fledgling CV storms since 2009 really... it's hard to argue that AGW is making the environment more favorable for intensification in the CV region.

The tracks are actually not abnormal. GaWx et. al. have done the work for this already, but something like 1 in 5 to 1 in 10 CV storms make it to the CONUS (more towards the latter in El Nino years like this one).

[PottercountyWXobserver]

No... each storm is a function of its own environment. You can't say that AGW is magically transforming garbage into Cat 1/2. And given the SAL/dry air/shear/etc.etc.etc. issues we've had with fledgling CV storms since 2009 really... it's hard to argue that AGW is making the environment more favorable for intensification in the CV region.

The tracks are actually not abnormal. GaWx et. al. have done the work for this already, but something like 1 in 5 to 1 in 10 CV storms make it to the CONUS (more towards the latter in El Nino years like this one).

I know each storm is a function of its own environment, but AGW has caused SSTs to become warmer in this general area and will continue to warm throughout the years, thus having an influence on the possibility of such storms having the right environment to develop quicker. As I have aluded to, SAL and other negative variables will continue to negate such AGW influences as long as SAL and others continue to be a factor, but once all factors are perfect, storms will mature much faster than normal and have a greater chance at recurve. I realize tracks from CV are already climatologically low for storms to threaten the east coast, but these odds will continue to widen as recurvatures become more probabilistic. I'm willing to bet long tracked systems straight off the african coast affecting areas between FL and NC will become lower chances as AGW increases. I'm also willing to bet, more tropical systems will continue having a greater chance at striking areas of Bermuda and potentially extreme eastern parts of Canada. Another sad but true aspect of AGW is the greater chance at a more northerly migrating jetstream, which in turn will cause a northern displacement of the Bermuda HP also causing a tendency to drive systems further to the north. The Atlantic HPs as you will act against the forces of the Coriolis effect and these HP steering currents act as a lid, the migration of the HPs to the north will cause the Coriolis effect to have a much more greater effect on "stronger" tropical systems causing the tropical systems to vere more right as they otherwise would. The Coriolis effect to potentially greater affect these "stronger" tropical systems after exiting off from Africa will be a much greater player than is currently realized. This plus the tendency for notherly migration HPs I think will be the main reason for the noticable affects of the fishiness of our tropical seasons.

[thewxmann]

I know each storm is a function of its own environment, but AGW has caused SSTs to become warmer in this general area and will continue to warm throughout the years, thus having an influence on the possibility of such storms having the right environment to develop quicker. As I have aluded to, SAL and other negative variables will continue to negate such AGW influences as long as SAL and others continue to be a factor, but once all factors are perfect, storms will mature much faster than normal and have a greater chance at recurve. I realize tracks from CV are already climatologically low for storms to threaten the east coast, but these odds will continue to widen as recurvatures become more probabilistic. I'm willing to bet long tracked systems straight off the african coast affecting areas between FL and NC will become lower chances as AGW increases. I'm also willing to bet, more tropical systems will continue having a greater chance at striking areas of Bermuda and potentially extreme eastern parts of Canada. Another sad but true aspect of AGW is the greater chance at a more northerly migrating jetstream, which in turn will cause a northern displacement of the Bermuda HP also causing a tendency to drive systems further to the north. The Atlantic HPs as you will act against the forces of the Coriolis effect and these HP steering currents act as a lid, the migration of the HPs to the north will cause the Coriolis effect to have a much more greater effect on "stronger" tropical systems causing the tropical systems to vere more right as they otherwise would. The Coriolis effect to potentially greater affect these "stronger" tropical systems after exiting off from Africa will be a much greater player than is currently realized. This plus the tendency for notherly migration HPs I think will be the main reason for the noticable affects of the fishiness of our tropical seasons.

You know what also causes SSTs to become warmer in the Atlantic? +AMO.

http://www.appinsys.com/globalwarming/AMO.htm

[PottercountyWXobserver]

I'm not arguing that the AMO doesn't have any influence on the atlantic SSTs, but the AMO and PDO are only a cycle on top of an AGW trend. The warming of the Atlantic and most global SSTs will be ever increasing as the globe warms regardless of the cyclical nature of the teleconnections.

The temperatures off Africa are only going to increase in anomaly. The second box drawn will increase the likelyhood of "stronger" systems threatening Bermuda and eastern Canada because of the much warmer northern Atlantic SSTs. Granted some of this is caused by the AMO, but a good amount is not.

[PottercountyWXobserver]

I though I would set up this thread to get some discussions on how AGW will continue to change our weather patterns. I posted this in the tropical thread, because I fully believe AGW will continue to change how our weather evolves and indivual weather patterns could be changed. I think AGW can explain how the northern jetstream is slowly migrating to the north due to the temperature gradients and why our winters have been unusally colder at times because a weakening jetstream could cause unusual meanderings.

I posted this in the tropical thread

I know each storm is a function of its own environment, but AGW has caused SSTs to become warmer in this general area and will continue to warm throughout the years, thus having an influence on the possibility of such storms having the right environment to develop quicker. As I have aluded to, SAL and other negative variables will continue to negate such AGW influences as long as SAL and others continue to be a factor, but once all factors are perfect, storms will mature much faster than normal and have a greater chance at recurve. I realize tracks from CV are already climatologically low for storms to threaten the east coast, but these odds will continue to widen as recurvatures become more probabilistic. I'm willing to bet long tracked systems straight off the african coast affecting areas between FL and NC will become lower chances as AGW increases. I'm also willing to bet, more tropical systems will continue having a greater chance at striking areas of Bermuda and potentially extreme eastern parts of Canada. Another sad but true aspect of AGW is the greater chance at a more northerly migrating jetstream, which in turn will cause a northern displacement of the Bermuda HP also causing a tendency to drive systems further to the north. The Atlantic HPs as you will act against the forces of the Coriolis effect and these HP steering currents act as a lid, the migration of the HPs to the north will cause the Coriolis effect to have a much more greater effect on "stronger" tropical systems causing the tropical systems to vere more right as they otherwise would. The Coriolis effect to potentially greater affect these "stronger" tropical systems after exiting off from Africa will be a much greater player than is currently realized. This plus the tendency for notherly migration HPs I think will be the main reason for the noticable affects of the fishiness of our tropical seasons.

This is just one example how I believe AGW will evolve going into the future, but please feel free to add any literature or thoughts on how you think AGW will cause weather patterns to change.

[andyhb]

You are killing Josh, one post at a time.

[SVT450R]

From wiki

''During warm phases of the AMO, the number of minor hurricanes (category 1 and 2) saw a modest increase.^[9] With full consideration of meteorological science, the number of tropical storms that can mature into severe hurricanes is much greater during warm phases of the AMO than during cool phases, at least twice as many; the AMO is reflected in the frequency of severe Atlantic hurricanes.^[6] The hurricane activity index is found to be highly correlated with the Atlantic multidecadal oscillation.''

[PhillipS]

You know what also causes SSTs to become warmer in the Atlantic? +AMO.

http://www.appinsys....warming/AMO.htm

I don't know whether you were being serious or tongue-in-cheek - but just so new readers don't get confused - the AMO is defined as the detrended Atlantic SSTs. So Atlantic SSTs drive the AMO, not the other way around. +AMO values are SST measurements above the trend and -AMO values are SST measurements below the trend.

So a better answer to your question of what causes SSTs to become warmer in the Atlantic - AGW. That's the source of the warming trend.

[aslkahuna]

Just a brief comment-yes globally the number of tropical cyclones is down and has been for some time. In fact, 2011 with 66 cyclones had the lowest number of observed cyclones since the start of the satellite era.

Steve

[ORH_wxman]

I don't know whether you were being serious or tongue-in-cheek - but just so new readers don't get confused - the AMO is defined as the detrended Atlantic SSTs. So Atlantic SSTs drive the AMO, not the other way around. +AMO values are SST measurements above the trend and -AMO values are SST measurements below the trend.

So a better answer to your question of what causes SSTs to become warmer in the Atlantic - AGW. That's the source of the warming trend.

When they detrend the data, its comparing it relative to the rest of the globe, so they are removing the backround warming signal when you use the detrended AMO. During the last -AMO phase, the actual north Atlantic SSTs were only slightly below the long term average and for only a brief time, yet hurricane activity was muted for much longer than the period of below average SSTs...this would argue that the relative trend is a factor too and not just the absolute anomalies. This would probably be linked to atmospheric response to the relative trend.

[tacoman25]

This much is clear: there is a much higher correlation with Atlantic storms/hurricanes to the AMO than there is to AGW at this point.

[ORH_wxman]

This much is clear: there is a much higher correlation with Atlantic storms/hurricanes to the AMO than there is to AGW at this point.

The literature supports AGW having a minimal impact on TCs anyway...overall number may decrease slightly and the overall intensity may increase slightly.

So its not a surprise that we aren't seeing any major effect thus far.