When will the multi-decade active era that began in 1995 end?

[cycloneye]

This thread is so priceless!

2014: it had been quiet lately, haven't it?
2015: Another disappointing year. Maybe we just came out of the active phase?
2016: Oops, maybe we spoke too soon?
2017: Maybe that was just the last hurrah.
2018: No, we definitely haven't left the active phase!
2019: LEAVE THE BAHAMAS ALONE!!!
2020: P-p-lease stop, we got the hint in 2017!

Maybe the thread should be renamed to "When will the multi-decade active era that began in 1995 end?"

Changed it.

[Hurricaneman]

Id say between 2030 and 2035 then we go into an inactive phase

[CFLHurricane]

Id say between 2030 and 2035 then we go into an inactive phase

Are inactive phases even a thing anymore due to global warming?

[Kazmit]

Id say between 2030 and 2035 then we go into an inactive phase

Are inactive phases even a thing anymore due to global warming?

Yes, there is long-term natural climate change as well.

[somethingfunny]

Id say between 2030 and 2035 then we go into an inactive phase

Are inactive phases even a thing anymore due to global warming?

If you look at the WPAC you'll see they're definitely in a less active period than they were in during the 70s-90s.

[wxman57]

Klotzbach and I were discussing this and it looks like it may have flipped in 2013 (cool AMO began). Tropics have yet to respond, though.

[underthwx]

How do you know when it ends?

[Category5Kaiju]

How do you know when it ends?

I would have to assume that we would need to go at least 15 or so consecutive years where none of the seasons really surpass the 1981-2020 average of 14 named storms (with most of the seasons having 14 or less NSs or something like that) and with each season not really exceeding the 1981-2020 averages of 7 hurricanes and 3 majors (with the vast majority of the seasons having 7 or less hurricanes and 3 or less majors). We could definitely still see Cat 5s and destructive hurricanes (as well as perhaps one or two slightly above average seasons with respect to the 14/7/3 metric), but crazy seasons like 2005, 2010, 2017, or 2020 in terms of NSs, ACE, and hurricane/major hurricane numbers would not happen. In my opinion it's kind of like that "how do you determine whether a species is truly extinct," so like if you intensely look for members of a certain species in its natural habitat and fail to find at least one over a course of 50 years, then you can likely determine that it is extinct. Quite similarly, if we have a decent number of consecutive years that do not really surpass 14/7/3, then the chances are we could conclude that we have entered an inactive phase. I personally have no idea when this will happen, although I would reasonably guess that given the last major active phase lasted roughly 40 years, the one we are currently in now would end around 2035 or so.

[al78]

Id say between 2030 and 2035 then we go into an inactive phase

Are inactive phases even a thing anymore due to global warming?

Yes, natural variability is superimposed on any long term trend. A warming trend doesn't stop severe cold winters from happening in the mid-latitudes, it just makes them less severe than they would have been without the warming trend (e.g. the UK is currently going through a prolonged cold spell).

[wxman57]

How do you know when it ends?

I would have to assume that we would need to go at least 15 or so consecutive years where none of the seasons really surpass the 1981-2020 average of 14 named storms (with most of the seasons having 14 or less NSs or something like that) and with each season not really exceeding the 1981-2020 averages of 7 hurricanes and 3 majors (with the vast majority of the seasons having 7 or less hurricanes and 3 or less majors). We could definitely still see Cat 5s and destructive hurricanes (as well as perhaps one or two slightly above average seasons with respect to the 14/7/3 metric), but crazy seasons like 2005, 2010, 2017, or 2020 in terms of NSs, ACE, and hurricane/major hurricane numbers would not happen. In my opinion it's kind of like that "how do you determine whether a species is truly extinct," so like if you intensely look for members of a certain species in its natural habitat and fail to find at least one over a course of 50 years, then you can likely determine that it is extinct. Quite similarly, if we have a decent number of consecutive years that do not really surpass 14/7/3, then the chances are we could conclude that we have entered an inactive phase. I personally have no idea when this will happen, although I would reasonably guess that given the last major active phase lasted roughly 40 years, the one we are currently in now would end around 2035 or so.

The number of seasonal storms has nothing to do with determining when the warm (active) AMO period ends, it all depends on when the AMO turns cool. As I stated previously, Klotzbach & I are thinking that the warm AMO may have ended in 2013.

[Weather Dude]

How do you know when it ends?

I would have to assume that we would need to go at least 15 or so consecutive years where none of the seasons really surpass the 1981-2020 average of 14 named storms (with most of the seasons having 14 or less NSs or something like that) and with each season not really exceeding the 1981-2020 averages of 7 hurricanes and 3 majors (with the vast majority of the seasons having 7 or less hurricanes and 3 or less majors). We could definitely still see Cat 5s and destructive hurricanes (as well as perhaps one or two slightly above average seasons with respect to the 14/7/3 metric), but crazy seasons like 2005, 2010, 2017, or 2020 in terms of NSs, ACE, and hurricane/major hurricane numbers would not happen. In my opinion it's kind of like that "how do you determine whether a species is truly extinct," so like if you intensely look for members of a certain species in its natural habitat and fail to find at least one over a course of 50 years, then you can likely determine that it is extinct. Quite similarly, if we have a decent number of consecutive years that do not really surpass 14/7/3, then the chances are we could conclude that we have entered an inactive phase. I personally have no idea when this will happen, although I would reasonably guess that given the last major active phase lasted roughly 40 years, the one we are currently in now would end around 2035 or so.

The number of seasonal storms has nothing to do with determining when the warm (active) AMO period ends, it all depends on when the AMO turns cool. As I stated previously, Klotzbach & I are thinking that the warm AMO may have ended in 2013.

How would it have ended in 2013 when we are on a 5 year active streak, with 2 of those being hyperactive? When the warm AMO began in 1995, there was an instant change to the seasonal numbers for the most part.

[Nuno]

I would have to assume that we would need to go at least 15 or so consecutive years where none of the seasons really surpass the 1981-2020 average of 14 named storms (with most of the seasons having 14 or less NSs or something like that) and with each season not really exceeding the 1981-2020 averages of 7 hurricanes and 3 majors (with the vast majority of the seasons having 7 or less hurricanes and 3 or less majors). We could definitely still see Cat 5s and destructive hurricanes (as well as perhaps one or two slightly above average seasons with respect to the 14/7/3 metric), but crazy seasons like 2005, 2010, 2017, or 2020 in terms of NSs, ACE, and hurricane/major hurricane numbers would not happen. In my opinion it's kind of like that "how do you determine whether a species is truly extinct," so like if you intensely look for members of a certain species in its natural habitat and fail to find at least one over a course of 50 years, then you can likely determine that it is extinct. Quite similarly, if we have a decent number of consecutive years that do not really surpass 14/7/3, then the chances are we could conclude that we have entered an inactive phase. I personally have no idea when this will happen, although I would reasonably guess that given the last major active phase lasted roughly 40 years, the one we are currently in now would end around 2035 or so.

The number of seasonal storms has nothing to do with determining when the warm (active) AMO period ends, it all depends on when the AMO turns cool. As I stated previously, Klotzbach & I are thinking that the warm AMO may have ended in 2013.

How would it have ended in 2013 when we are on a 5 year active streak, with 2 of those being hyperactive? When the warm AMO began in 1995, there was an instant change to the seasonal numbers for the most part.

And what factors are leading to this belief that the warm AMO has ended? 8 years is quite a long time to play catch up.

[Shell Mound]

Klotzbach and I were discussing this and it looks like it may have flipped in 2013 (cool AMO began). Tropics have yet to respond, though.

If the tropics have yet to respond, does that imply the +AMO is still in effect, or are other factors offsetting the onset of the -AMO?

[CyclonicFury]

The number of seasonal storms has nothing to do with determining when the warm (active) AMO period ends, it all depends on when the AMO turns cool. As I stated previously, Klotzbach & I are thinking that the warm AMO may have ended in 2013.

How would it have ended in 2013 when we are on a 5 year active streak, with 2 of those being hyperactive? When the warm AMO began in 1995, there was an instant change to the seasonal numbers for the most part.

And what factors are leading to this belief that the warm AMO has ended? 8 years is quite a long time to play catch up.

I would assume it would have something to do with the recent persistent cool SST anomaly over the far north Atlantic, though I wonder if that is related to melting Arctic sea ice and not the AMO itself. CSU's AMO index has been persistently negative since 2014, though since CSU updated their AMO website the values are not publicly available.

However, the activity of the Atlantic basin since 2016 has been nothing like what we witnessed from 1970-1994. There has been a total of 21 major hurricanes in the last 5 years in the Atlantic, an average of over 4 per year, which is significant since not one season from 1970-1994 had 4 or more major hurricanes.

Klotzbach himself seems to no longer think the Atlantic active era is over:
 https://twitter.com/philklotzbach/status/1319276340269305858

[Nuno]

How would it have ended in 2013 when we are on a 5 year active streak, with 2 of those being hyperactive? When the warm AMO began in 1995, there was an instant change to the seasonal numbers for the most part.

And what factors are leading to this belief that the warm AMO has ended? 8 years is quite a long time to play catch up.

I would assume it would have something to do with the recent persistent cool SST anomaly over the far north Atlantic, though I wonder if that is related to melting Arctic sea ice and not the AMO itself. CSU's AMO index has been persistently negative since 2014, though since CSU updated their AMO website the values are not publicly available.

However, the activity of the Atlantic basin since 2016 has been nothing like what we witnessed from 1970-1994. There has been a total of 21 major hurricanes in the last 5 years in the Atlantic, an average of over 4 per year, which is significant since not one season from 1970-1994 had 4 or more major hurricanes.

Klotzbach himself seems to no longer think the Atlantic active era is over:
[url]https://twitter.com/philklotzbach/status/1319276340269305858][/url]

Part of the issue too is that our sample size of accurate seasonal statistics is so small, that we truly have no idea how long cycles are supposed to be. Was 30 years an anomalously short cycle? I wish we knew the previous millennium's data...

[weeniepatrol]

VERY interesting thread to say the least...

 https://twitter.com/MichaelEMann/status/1367552447107989510

[Steve]

Here’s his article. It doesn’t exist. It was a figment of modeling. People took themselves seriously on this here thread. For the downcasters, you made up your idea it was over or ending any number of times arguing about an oscillation that Mann coined. Time to delete this thread and send it to the archives.

http://www.realclimate.org/index.php/ar ... cillation/

[ncforecaster89]

VERY interesting thread to say the least...

https://twitter.com/MichaelEMann/status/1367552447107989510

As a scientist (degreed meteorologist), myself, I’m amazed by how much these supposed climate experts allow their own presuppositions to influence their own desired conclusions. Simply put, it’s very misguided to subscribe to the belief that human effects are legitimately outweighing natural variability in regards to climate variability. The foundation of science at its most basic level is based foremost on objectivity. I take no definitive position on AGW because there is too much conflicting data/modeling and only a relatively short period of record to make definitive conclusions.

Consequently, the aforementioned article does nothing to dispel the natural variability referred to as the AMO.

[Weather Dude]

I find it kind of odd that this guy comes up with this idea of a natural cycling Atlantic, which makes sense when looking at the charts of past hurricane seasons, and then all of a sudden when we are on an active streak, he comes out and says that it's because of human caused climate change... My question is, what makes this active phase any different than past ones? I mean it's not like we had anything near the level of technology back then like we do today so of course it's going to seem like the number of storms is much higher now than it was back then. To me the climate is always changing and it will continue to change either way over time. I just can't stand how nowadays something happens (tornado, hurricane, blizzard, etc.) and people just blame it on climate change. I could go on but I don't want start a dispute so I'll stop here. It just seems weird how he would just completely flip like that. But who knows, maybe it's just me.

[toad strangler]

I find it kind of odd that this guy comes up with this idea of a natural cycling Atlantic, which makes sense when looking at the charts of past hurricane seasons, and then all of a sudden when we are on an active streak, he comes out and says that it's because of human caused climate change... My question is, what makes this active phase any different than past ones? I mean it's not like we had anything near the level of technology back then like we do today so of course it's going to seem like the number of storms is much higher now than it was back then. To me the climate is always changing and it will continue to change either way over time. I just can't stand how nowadays something happens (tornado, hurricane, blizzard, etc.) and people just blame it on climate change. I could go on but I don't want start a dispute so I'll stop here. It just seems weird how he would just completely flip like that. But who knows, maybe it's just me.

It's not just you