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

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

#481 Postby Chris90 » Wed Nov 24, 2021 6:08 pm

I think 2021 is just simply showing balance in the atmosphere, and isn't necessarily a sign that we're entering a multi-decade quiet period. You have to have 2021s to balance out 2018s. 2021 may have only had 10 major strength cyclones in the N. Hemisphere so far (years not done yet) but 2018 had 10 Category 5s in the N. Hemisphere, and that's just Cat 5s, not including all the Cat 3s and 4s.

I saw something a couple weeks ago that I think was posted here, about October being the only October that was this inactive besides October of 1977 for the N. Hemisphere tropics. I live in Illinois, the winter of 1977-1978 is on record as being the worst for the state and most of the Midwest. The state experienced 18 winter storms breaking the previous record of 12. Maybe October 2021 matching up with October of 1977 is an indicator that we're about to experience another winter like 1977-78, and while 2021 experienced anomalously decreased energy in the tropics, maybe the N. Hemisphere winter will experience anomalously increased energy in the mid and northern latitudes. It might simply be a case of greatest atmospheric energy migrating north out of the tropics for a period of time, and we might see it gradually return over the next 12-24 months.

I'm interested to see how the southern hemisphere behaves over the next 6 months. Will it also be below average, or will it be average or above average?
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Re: When will the multi-decade active era that began in 1995 end?

#482 Postby AnnularCane » Wed Nov 24, 2021 7:05 pm

Yes. Seems like someone or another has been speculating that possibly we've entered the "quiet period" for years now. At this point I just feel like I'll believe it when I see it, and it may take several years.
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Re: When will the multi-decade active era that began in 1995 end?

#483 Postby kevin » Thu Nov 25, 2021 3:17 am

If it was just the Atlantic that suddenly dropped activity, I might also speculate about an end of the active era. But since it was the entire globe that suddenly saw no to little storm development after September of this year, I'm not that inclined to relate it to the Atlantic active era.
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Re: When will the multi-decade active era that began in 1995 end?

#484 Postby AlphaToOmega » Sat Apr 02, 2022 7:25 pm

Contrary to what some are saying about climate change putting us into a hybrid -AMO/+AMO phase, I would like to opine that climate change is going to put us into a perpetual +AMO phase.

The AMO, according to Enfield et al., is the difference between the SSTAs in the North Atlantic (0 to 70N) and the global SSTAs.

Climate change is impacting the whole planet, but in terms of SSTAs, it is impacting the Northern Hemisphere more than the Southern Hemisphere. From 1982 to 2021, the SSTAs in the Northern Hemisphere increased, according to OISSTv2 analysis, by 0.673 C; in the Southern Hemisphere, that was 0.427 C.

If the Northern Hemisphere continues to outwarm the Southern Hemisphere, it would mean that the North Atlantic (which is part of the Northern Hemisphere) would be warming more quickly than the Earth as a whole, thus making the AMO more positive.
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Re: When will the multi-decade active era that began in 1995 end?

#485 Postby Yellow Evan » Sat Apr 02, 2022 7:44 pm

:uarrow: NHEM vs SHEM warmth is an oscillation. It’s possible AGW is influencing it however it is a bit overly simplistic to just compare 1982 to 2021. More NHEM warmth wouldn’t necessarily mean more AMO (though it is heavily correlated positively to the strength of the WAM) because more warmth also means more Greenland ice sheet melting, which would potentially drastically slow down the AMOC, which would favor -AMO.

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

#486 Postby Shell Mound » Sun Apr 03, 2022 3:19 am

AlphaToOmega wrote:Contrary to what some are saying about climate change putting us into a hybrid -AMO/+AMO phase, I would like to opine that climate change is going to put us into a perpetual +AMO phase.

The AMO, according to Enfield et al., is the difference between the SSTAs in the North Atlantic (0 to 70N) and the global SSTAs.

Climate change is impacting the whole planet, but in terms of SSTAs, it is impacting the Northern Hemisphere more than the Southern Hemisphere. From 1982 to 2021, the SSTAs in the Northern Hemisphere increased, according to OISSTv2 analysis, by 0.673 C; in the Southern Hemisphere, that was 0.427 C.

The North Atlantic is only a small part of the Northern Hemisphere. The Pacific and Indian basins comprise considerably larger portions of the NHEM and hold much more warmth. Because the combined surface area of the Pacific and Indian basins is much larger than that of the Atlantic, those basins’ SSTs have warmed more in absolute terms than the Atlantic has during the most recent phase of global warming. Combined with the influence of freshwater influx via Greenland ice-melt and North Atlantic Deep Water (NADW), the warming of the Pacific and Indian basins works with the slowing AMOC to favour a net -AMO on balance.
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Re: When will the multi-decade active era that began in 1995 end?

#487 Postby StormPyrate » Sun Apr 03, 2022 7:17 am

It will never end.
We are naming storms now that a few decades ago we did not even know existed.
Its always going to be more active than EVER before because we know more.
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Re: When will the multi-decade active era that began in 1995 end?

#488 Postby Shell Mound » Wed Apr 06, 2022 2:18 am

Yellow Evan wrote::uarrow: NHEM vs SHEM warmth is an oscillation. It’s possible AGW is influencing it however it is a bit overly simplistic to just compare 1982 to 2021. More NHEM warmth wouldn’t necessarily mean more AMO (though it is heavily correlated positively to the strength of the WAM) because more warmth also means more Greenland ice sheet melting, which would potentially drastically slow down the AMOC, which would favor -AMO.

https://media.discordapp.net/attachments/733552978572869632/941091547166957588/image0.jpg

 https://twitter.com/dmorris9661/status/1511407690882375684




Does this qualify as possible evidence that we have entered a -AMO?
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Re: When will the multi-decade active era that began in 1995 end?

#489 Postby Yellow Evan » Wed Apr 06, 2022 2:27 am

Shell Mound wrote:
Yellow Evan wrote::uarrow: NHEM vs SHEM warmth is an oscillation. It’s possible AGW is influencing it however it is a bit overly simplistic to just compare 1982 to 2021. More NHEM warmth wouldn’t necessarily mean more AMO (though it is heavily correlated positively to the strength of the WAM) because more warmth also means more Greenland ice sheet melting, which would potentially drastically slow down the AMOC, which would favor -AMO.

https://media.discordapp.net/attachments/733552978572869632/941091547166957588/image0.jpg

https://twitter.com/dmorris9661/status/1511407690882375684

Does this qualify as possible evidence that we have entered a -AMO?


As I’ve said in past, no. Just because we are not the classic EOF1 AMO’s that we saw from 1995 to 2010 or so doesn’t mean we have a -AMO, and we wouldn’t really be expected to anyway given the last couple +AMO’s have lasted 35-45 years. We are just in a period of EOF 2/3 +AMO’s during the spring until Africa and the +AMM take over. The 1950’s were similar so it wouldn’t be the first time this has happened either.
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Re: When will the multi-decade active era that began in 1995 end?

#490 Postby Shell Mound » Wed Apr 06, 2022 3:06 am

Yellow Evan wrote:
Shell Mound wrote:
Yellow Evan wrote::uarrow: NHEM vs SHEM warmth is an oscillation. It’s possible AGW is influencing it however it is a bit overly simplistic to just compare 1982 to 2021. More NHEM warmth wouldn’t necessarily mean more AMO (though it is heavily correlated positively to the strength of the WAM) because more warmth also means more Greenland ice sheet melting, which would potentially drastically slow down the AMOC, which would favor -AMO.

https://media.discordapp.net/attachments/733552978572869632/941091547166957588/image0.jpg

https://twitter.com/dmorris9661/status/1511407690882375684

Does this qualify as possible evidence that we have entered a -AMO?


As I’ve said in past, no. Just because we are not the classic EOF1 AMO’s that we saw from 1995 to 2010 or so doesn’t mean we have a -AMO, and we wouldn’t really be expected to anyway given the last couple +AMO’s have lasted 35-45 years. We are just in a period of EOF 2/3 +AMO’s during the spring until Africa and the +AMM take over. The 1950’s were similar so it wouldn’t be the first time this has happened either.

Couldn’t climate change have shortened the most recent +AMO cycle and caused us to enter a period of “hybrids” (springtime EOF 2/3 with a strong WAM)?
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Re: When will the multi-decade active era that began in 1995 end?

#491 Postby Yellow Evan » Wed Apr 06, 2022 3:28 am

Shell Mound wrote:
Yellow Evan wrote:
Shell Mound wrote:https://twitter.com/dmorris9661/status/1511407690882375684

Does this qualify as possible evidence that we have entered a -AMO?


As I’ve said in past, no. Just because we are not the classic EOF1 AMO’s that we saw from 1995 to 2010 or so doesn’t mean we have a -AMO, and we wouldn’t really be expected to anyway given the last couple +AMO’s have lasted 35-45 years. We are just in a period of EOF 2/3 +AMO’s during the spring until Africa and the +AMM take over. The 1950’s were similar so it wouldn’t be the first time this has happened either.

Couldn’t climate change have shortened the most recent +AMO cycle and caused us to enter a period of “hybrids” (springtime EOF 2/3 with a strong WAM)?


More “hybrids”? Yes. Changes to the length of the AMO cycle? I’d need more convincing.
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Re: When will the multi-decade active era that began in 1995 end?

#492 Postby AlphaToOmega » Wed Apr 06, 2022 4:05 am

Yellow Evan wrote:
Shell Mound wrote:
Yellow Evan wrote:
As I’ve said in past, no. Just because we are not the classic EOF1 AMO’s that we saw from 1995 to 2010 or so doesn’t mean we have a -AMO, and we wouldn’t really be expected to anyway given the last couple +AMO’s have lasted 35-45 years. We are just in a period of EOF 2/3 +AMO’s during the spring until Africa and the +AMM take over. The 1950’s were similar so it wouldn’t be the first time this has happened either.

Couldn’t climate change have shortened the most recent +AMO cycle and caused us to enter a period of “hybrids” (springtime EOF 2/3 with a strong WAM)?


More “hybrids”? Yes. Changes to the length of the AMO cycle? I’d need more convincing.


According to the Enfield AMO index, we are still solidly in a +AMO phase.

2000 -0.098 -0.052 0.089 0.028 0.091 -0.032 0.058 0.089 0.087 -0.054 -0.067 -0.141
2001 -0.142 -0.041 0.000 -0.026 -0.024 0.184 0.121 0.163 0.272 0.237 0.142 0.199
2002 0.167 0.150 0.130 0.013 -0.063 -0.131 -0.080 0.092 0.065 0.097 0.005 -0.010
2003 0.036 -0.027 0.098 0.064 0.136 0.191 0.261 0.401 0.437 0.411 0.209 0.209
2004 0.196 0.195 0.143 0.093 -0.009 0.163 0.213 0.302 0.226 0.227 0.206 0.172
2005 0.096 0.111 0.269 0.277 0.278 0.312 0.432 0.425 0.404 0.223 0.125 0.201
2006 0.108 0.060 0.045 0.182 0.293 0.318 0.359 0.386 0.349 0.319 0.274 0.156
2007 0.156 0.202 0.112 0.144 0.096 0.073 0.114 0.040 0.083 0.143 0.161 0.096
2008 0.015 0.113 0.143 0.028 0.157 0.241 0.191 0.160 0.183 0.087 -0.014 0.003
2009 -0.074 -0.179 -0.175 -0.146 -0.077 0.106 0.213 0.137 0.042 0.149 0.054 0.067
2010 0.024 0.162 0.272 0.410 0.444 0.432 0.434 0.510 0.434 0.308 0.220 0.192
2011 0.128 0.092 0.040 0.076 0.136 0.163 0.076 0.131 0.128 0.047 -0.086 -0.060
2012 -0.081 -0.012 0.010 0.064 0.148 0.284 0.359 0.415 0.432 0.313 0.149 0.125
2013 0.112 0.099 0.142 0.120 0.085 0.030 0.174 0.178 0.239 0.331 0.112 0.020
2014 -0.078 -0.059 -0.097 -0.110 -0.018 0.046 0.205 0.318 0.294 0.276 0.048 0.042
2015 -0.025 -0.020 -0.146 -0.088 0.028 0.012 0.115 0.162 0.283 0.308 0.170 0.212
2016 0.214 0.139 0.171 0.160 0.327 0.392 0.415 0.440 0.441 0.363 0.374 0.318
2017 0.208 0.210 0.150 0.266 0.297 0.291 0.285 0.293 0.333 0.416 0.335 0.347
2018 0.156 0.045 0.115 0.047 -0.018 -0.028 0.000 0.095 0.145 0.126 -0.138 -0.077
2019 -0.032 0.063 0.104 0.106 0.071 0.156 0.335 0.321 0.228 0.141 0.093 0.147
2020 0.079 0.339 0.351 0.352 0.249 0.255 0.347 0.431 0.302 0.295 0.118 0.168
2021 0.132 0.144 0.118 0.060 0.077 0.144 0.215 0.250 0.408 0.481 0.451 0.258
2022 0.182 0.139


Source: https://psl.noaa.gov/data/correlation/amon.us.data
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Re: When will the multi-decade active era that began in 1995 end?

#493 Postby wxman57 » Wed Apr 06, 2022 6:24 am

Note that the Klotzbach/Gray method of calculating AMO has -0.81C for February. Trending cooler.

Well, heading to the airport now to head to South Padre for the National Tropical Weather Conference. Should be flying with Brian.
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Re: When will the multi-decade active era that began in 1995 end?

#494 Postby Category5Kaiju » Wed Apr 06, 2022 11:32 am

Ok, I have a couple of key points that I think are worth making.

First of all, I see that there's this talk of us being in a hybrid AMO phase. Whether it is leaning more positive or negative can be debated, but one thing's quite obvious: since this began in 2016, whatever this hybrid AMO phase truly is has been associated with above average seasons, each of which featured at least one highly destructive and powerful hurricane. Matthew, Irma, Dorian, Eta, and so forth. It is also quite apparent that each season's most powerful storm has been a 155 mph Cat 4 hurricane or stronger. This sort of behavior in the Atlantic basin is, quite frankly, unprecedented for all we know, especially if you look back at reliable historical records.

Second of all, if we are talking in terms of ACE, I think we should take it a step back and ask ourselves, what is it about 2017 and 2020 that made them hyperactive? What were the key factors for each season that could have contributed to such, and how similar is the overall comparison of factors? More importantly, were such factors around in hyperactive years like 1995, 2004, 2005, and 2010, before this hybrid AMO began? Personally, the fact that we nevertheless had 2 hyperactive years during this interesting AMO period makes me think that there may not really be any huge detriment to ACE total and this hybrid AMO. And, of course, it's very early to tell, but if for some reason 2022 ends up as a hyperactive year, then that sentiment would be further bolstered to an extent.

It's definitely an interesting topic to talk about.
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Re: When will the multi-decade active era that began in 1995 end?

#495 Postby cycloneye » Wed Apr 06, 2022 2:15 pm

Category5Kaiju wrote:Ok, I have a couple of key points that I think are worth making.

First of all, I see that there's this talk of us being in a hybrid AMO phase. Whether it is leaning more positive or negative can be debated, but one thing's quite obvious: since this began in 2016, whatever this hybrid AMO phase truly is has been associated with above average seasons, each of which featured at least one highly destructive and powerful hurricane. Matthew, Irma, Dorian, Eta, and so forth. It is also quite apparent that each season's most powerful storm has been a 155 mph Cat 4 hurricane or stronger. This sort of behavior in the Atlantic basin is, quite frankly, unprecedented for all we know, especially if you look back at reliable historical records.

Second of all, if we are talking in terms of ACE, I think we should take it a step back and ask ourselves, what is it about 2017 and 2020 that made them hyperactive? What were the key factors for each season that could have contributed to such, and how similar is the overall comparison of factors? More importantly, were such factors around in hyperactive years like 1995, 2004, 2005, and 2010, before this hybrid AMO began? Personally, the fact that we nevertheless had 2 hyperactive years during this interesting AMO period makes me think that there may not really be any huge detriment to ACE total and this hybrid AMO. And, of course, it's very early to tell, but if for some reason 2022 ends up as a hyperactive year, then that sentiment would be further bolstered to an extent.

It's definitely an interesting topic to talk about.


That is why this thread has kept active since June of 2014 because of the many factors that people have to analize and if you check the pages, there is plenty of good info.
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Re: When will the multi-decade active era that began in 1995 end?

#496 Postby NotSparta » Wed Apr 06, 2022 2:43 pm

Shell Mound wrote:
Yellow Evan wrote::uarrow: NHEM vs SHEM warmth is an oscillation. It’s possible AGW is influencing it however it is a bit overly simplistic to just compare 1982 to 2021. More NHEM warmth wouldn’t necessarily mean more AMO (though it is heavily correlated positively to the strength of the WAM) because more warmth also means more Greenland ice sheet melting, which would potentially drastically slow down the AMOC, which would favor -AMO.

https://media.discordapp.net/attachments/733552978572869632/941091547166957588/image0.jpg

https://twitter.com/dmorris9661/status/1511407690882375684

Does this qualify as possible evidence that we have entered a -AMO?


The fact that we have so many above average seasons and any hyperactive seasons at all means it does not
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Re: When will the multi-decade active era that began in 1995 end?

#497 Postby Shell Mound » Fri Apr 08, 2022 6:24 am

NotSparta wrote:
Shell Mound wrote:
Yellow Evan wrote::uarrow: NHEM vs SHEM warmth is an oscillation. It’s possible AGW is influencing it however it is a bit overly simplistic to just compare 1982 to 2021. More NHEM warmth wouldn’t necessarily mean more AMO (though it is heavily correlated positively to the strength of the WAM) because more warmth also means more Greenland ice sheet melting, which would potentially drastically slow down the AMOC, which would favor -AMO.

https://media.discordapp.net/attachments/733552978572869632/941091547166957588/image0.jpg

https://twitter.com/dmorris9661/status/1511407690882375684

Does this qualify as possible evidence that we have entered a -AMO?

The fact that we have so many above average seasons and any hyperactive seasons at all means it does not

What about precipitation patterns? Since 2017 only one season had a profile remotely resembling that of a hyperactive season. Also, compared to previous hyperactive years from 1995 to 2012, 2017 and 2020 featured considerably lower precipitation over the Caribbean and large portions of the MDR, suggesting that the +AMO has weakened considerably, if not completely reversed itself, post 2012:

Image

I think some storms in the late 1970s and much of the 1980s were so badly underestimated that at least a few seasons could have been hyperactive from 1970–94.
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Re: When will the multi-decade active era that began in 1995 end?

#498 Postby Shell Mound » Tue Apr 12, 2022 4:09 am

Shell Mound wrote:
NotSparta wrote:
Shell Mound wrote:https://twitter.com/dmorris9661/status/1511407690882375684

Does this qualify as possible evidence that we have entered a -AMO?

The fact that we have so many above average seasons and any hyperactive seasons at all means it does not

What about precipitation patterns? Since 2017 only one season had a profile remotely resembling that of a hyperactive season. Also, compared to previous hyperactive years from 1995 to 2012, 2017 and 2020 featured considerably lower precipitation over the Caribbean and large portions of the MDR, suggesting that the +AMO has weakened considerably, if not completely reversed itself, post 2012:

https://i.ibb.co/XX79nBq/AMOrecord-1.png

I think some storms in the late 1970s and much of the 1980s were so badly underestimated that at least a few seasons could have been hyperactive from 1970–94.

:uarrow: Doesn’t this evidence suggest that the +AMO has likely ended since 2013? During the hyperactive seasons of 2017 and 2020, precipitation rates over the MDR and Caribbean were lower than in the hyperactive years that occurred between 1995 and 2010. This is consistent with the hypothesis that climate change, which promotes warmer SST in the subtropics, also leads to greater stability and anticyclonic wave-breaking (TUTT-related shear) over the MDR and Caribbean. The point is that the background state has changed due to climate change in such a way as to greatly weaken and/or shorten, if not reverse, the most recent +AMO cycle.
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Re: When will the multi-decade active era that began in 1995 end?

#499 Postby Shell Mound » Tue Apr 12, 2022 4:31 am

Top reasons why the +AMO has likely ended post 2010:

  • There have been only two hyperactive seasons (2017, 2020) over the past decade, compared to seven (1995, 1996, 1998, 1999, 2003, 2004, 2005) over a comparable decade
  • Average precipitation over the MDR and Caribbean during two most recent hyperactive seasons was far lower than the mean of the seven previous hyperactive years
  • Instability over the MDR and Caribbean during the peak months of ASO has been much lower post 2010 than before
  • The subtropics have been consistently warmer than the tropics during most of the past ten seasons
  • Long-tracked majors in the MDR and Caribbean have become much less frequent than they used to be
  • Seasonal activity is being inflated by short-lived systems in the subtropics that likely went unclassified/undetected prior to advances in detection and changes to the criteria for classification
  • More ACE is being generated in the subtropics instead of the tropics, while overall ACE is still decreasing due to the fact that the tropics are generating fewer long-lived, intense storms
  • While ACE is still averaging somewhat higher than during the previous -AMO, it is still lower than during the unquestionably +AMO period of 1995–2010; given that warmer global SST due to climate change may result in higher overall ACE in modern-day -AMOs than in pre-global-warming -AMOs, this should not be used to claim that the most recent +AMO did not end
  • The changes in the distribution of precipitation and ACE, as well as the decrease in long-lived, intense systems in the tropics, correlates well with the end of the +AMO
  • In turn, the end of the +AMO can be attributable to changes in the SST over the far northern North Atlantic that have been brought about by Greenland ice melt and freshwater influx, which in turn is attributable to global warming
Conclusion: while there is still uncertainty, the weight of evidence suggests that the most recent +AMO ended circa 2010 and no later than 2013, and that this +AMO lasted for a shorter period than previous +AMOs due to the background changes brought about by climate change. Because climate change results in warmer absolute SST globally, we could still end up with higher seasonal ACE in a -AMO cycle today than in past -AMO cycles, yet still be in a -AMO rather than a +AMO. It would be misleading to use a single piece of evidence such as the warm Canary Current and active WAM to argue that we are still in a +AMO, at least in my view.
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Re: When will the multi-decade active era that began in 1995 end?

#500 Postby NotSparta » Tue Apr 12, 2022 8:28 am

Shell Mound wrote:Top reasons why the +AMO has likely ended post 2010:

  • There have been only two hyperactive seasons (2017, 2020) over the past decade, compared to seven (1995, 1996, 1998, 1999, 2003, 2004, 2005) over a comparable decade
  • Average precipitation over the MDR and Caribbean during two most recent hyperactive seasons was far lower than the mean of the seven previous hyperactive years
  • Instability over the MDR and Caribbean during the peak months of ASO has been much lower post 2010 than before
  • The subtropics have been consistently warmer than the tropics during most of the past ten seasons
  • Long-tracked majors in the MDR and Caribbean have become much less frequent than they used to be
  • Seasonal activity is being inflated by short-lived systems in the subtropics that likely went unclassified/undetected prior to advances in detection and changes to the criteria for classification
  • More ACE is being generated in the subtropics instead of the tropics, while overall ACE is still decreasing due to the fact that the tropics are generating fewer long-lived, intense storms
  • While ACE is still averaging somewhat higher than during the previous -AMO, it is still lower than during the unquestionably +AMO period of 1995–2010; given that warmer global SST due to climate change may result in higher overall ACE in modern-day -AMOs than in pre-global-warming -AMOs, this should not be used to claim that the most recent +AMO did not end
  • The changes in the distribution of precipitation and ACE, as well as the decrease in long-lived, intense systems in the tropics, correlates well with the end of the +AMO
  • In turn, the end of the +AMO can be attributable to changes in the SST over the far northern North Atlantic that have been brought about by Greenland ice melt and freshwater influx, which in turn is attributable to global warming
Conclusion: while there is still uncertainty, the weight of evidence suggests that the most recent +AMO ended circa 2010 and no later than 2013, and that this +AMO lasted for a shorter period than previous +AMOs due to the background changes brought about by climate change. Because climate change results in warmer absolute SST globally, we could still end up with higher seasonal ACE in a -AMO cycle today than in past -AMO cycles, yet still be in a -AMO rather than a +AMO. It would be misleading to use a single piece of evidence such as the warm Canary Current and active WAM to argue that we are still in a +AMO, at least in my view.


Top reasons why the +AMO has (functionally) likely not ended post 2010:

  • The last below average season was literally 7 years ago
  • In 25 years, the last -AMO had 2 above average seasons (13 below)
  • Since 2011 (11 years), there have been 8 above average seasons (3 below)
  • 2017
  • 2020

Just because the hyperactive seasons don't look "classic" or that we haven't had the same extreme activity that is excessive even for a +AMO doesn't mean it has ended. If we were truly in a -AMO, we would not have seen 2016-21 (and likely 2022). The past 6 years (or even going back to 2010) has had activity far and away above what you'd expect in a -AMO. I understand making this argument in 2014, 2015, 2016, even early 2017. But this argument has become harder and harder to defend with time. Just a fool's errand to argue that we're in a -AMO when we're probably at the precipice of yet another active season (ACE is not significantly affected by short lived storms!). If ACE is this high even in a -AMO due to AGW, we may as well be in a permanent +AMO, because the recent activity is far more consistent with +AMO
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