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AbruptSLR

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Re: AMOC (Gulf Stream Current) Collapsing
« Reply #50 on: August 15, 2021, 06:13:25 PM »
...
And, as you surely know, Antarctic deep water formation has gone back into a funk. It briefly revived a few years back when sea ice extent declined around Antarctica, but it has gone back into a coma. Hansen is more concerned about the shut down in the near future of Antarctic deep water formation than complete shut down of the AMOC. He is, of course, correct.

Expect warming to accelerate even more as sulfate aerosol levels drop with the closing of coal plants. That has happened in the U.S. but not India and China where coal is still king.

We're not totally fucked but we fucked where it hurts.

You are correct that Hansen (whom I agree with, and whose work I based my Maximum Credible Domino Scenario-Bayesian Network, MCDS-BN, projections) is concerned that the Southern Ocean Meridional Overturning Circulation (SMOC, that is close related to Antarctic Bottom Water, AABW, formation) will temporarily shutdown circa 2050 (see the first image), which his (& his associate's) 2014 model projections (released in 2015 and published in 2016) would correspond to a marked slowdown of the AMOC circa 2100 (see the second image); due to the bipolar seesaw system (& subsystems) illustrated in the third image.

In the linked 2021 article (see extracts below), Hansen makes it clear that consensus climate science model projections (e.g.: CMIP) significantly overestimate the current mixing of the ocean (i.e.: they assume fast mixing) that result in relatively slow increases in GMSTA, while Hansen's (& his associate's) model projections were tuned to match the observed slower ocean mixing (resulting in a more stratified ocean with a stronger 'pattern effect' that consensus climate scientists do not consider in calculating ECS, but which the MCDS-BN considers when estimating ECSeff) as illustrated by the fourth image.

Thus, I believe that consensus climate science projections severely underestimate the climate risks of the deep uncertainties associated with the credible interactions between the MOC (including both the AMOC and the SMOC) and possible freshwater fluxes (particularly from ice melting) into the ocean in coming decades.

Title: "Foreword: Uncensored Science Is Crucial for Global Conservation" by James Hansen 2021

www.columbia.edu/~jeh1/mailings/2021/20210614_ForewordHansen.pdf

Extract: "In October 2006 we – Reto Ruedy, Makiko Sato and I – made a model run with meltwater injection from Antarctica and Greenland. The initial ice melt rate was from observations; it then increased with a 10-year doubling time up to a sea level rise of 5 meters. Most of that water could be provided by West Antarctic ice, which rests on bedrock below sea level (Foreword Figure 2). Deep valley outlets on East Antarctica (Greenbaum et al., 2015) and Greenland (Catania et al., 2020) expose additional ice to contact with ocean water.

Within several decades the North Atlantic and Southern Ocean Overturning Circulations (dubbed AMOC and SMOC) had shut down. In a hot, warming world, sea ice around Antarctica held steady and then expanded northward.

I had a suspicion about a problem in ocean models. When we doubled atmospheric CO2, we found that global surface temperature after 100 years had only achieved 60 percent of its final warming. Could mixing of heat into the ocean really slow down the surface response that much? Such a long delay was not expected by the legendary Jule Charney (Hansen, 2022f).

Response function information might spur more focus on ocean mixing and on observations to test the reality of ocean mixing in all models. Such a focus on the key (real world and model) physics is analogous to how Jule Charney focused his famous investigation of climate sensitivity (Charney et al., 1979). Charney would have jumped eagerly on the issue of ocean mixing and climate response time, but he died young, in 1981.

Argo floats (Argo, 2021) dive to a two-kilometer depth, rise to the surface while making measurements, and radio the data to a satellite. Precise ocean temperatures measured by the Argo floats were the data needed to define Earth’s energy imbalance. That imbalance is important: it defines how much additional global warming is in the pipeline and it thus informs us about actions needed to stop further global warming.

Accurate determination of Earth’s energy imbalance meant that we had two major “knowns” about the climate system, the other being observed global warming in the past century. There are three major unknowns: climate sensitivity to a forcing, the net climate forcing, and the delay of surface temperature change caused by ocean mixing of heat.

Our paper also confirmed the suspicion that ocean models mixed heat into the deep ocean too efficiently, but it did not tell us why. Did models create an artificial diffusion of heat via their finite differencing approximation of the equations of motion? Did the approximations used to represent mixing on scales smaller than the model’s grid cause too much mixing? Did the coarse vertical resolution of ocean models cause excessive downward mixing?

Whatever the reason(s), excessive mixing makes it difficult to maintain a low-density ocean surface layer fed by meltwater. Therefore, SMOC and AMOC shut down more readily in the real world than in models. SMOC is more important than AMOC because SMOC shutdown accelerates Antarctic ice melt and sea level rise. The high sensitivity of SMOC implies that sea level rise could run out of control within the next few decades.

In early 2014 we reran climate simulations with our latest climate model; results were similar to those in 2006.

Prior analyses of ocean circulation focused on AMOC

That focus is understandable. Shutdown of AMOC yields large climate change in the North Atlantic with downstream impact on Europe. The reduced northward ocean heat transport also warms the Southern Ocean – an interhemispheric “seesaw” effect (Stocker, 1998). However, the research community and IPCC concluded that AMOC would not shut down this century; it would only slow down somewhat more than it has already (IPCC, 2019).

Our conclusions differed dramatically. We found that SMOC is more important than AMOC because of its effect on future sea level rise. For business-as-usual scenarios used by IPCC, we found that SMOC would shut down by midcentury (Foreword Figure 4). AMOC would also shut down this century and would not recover for centuries. Our approach to the problem also differed greatly from that of IPCC. While IPCC relies heavily on ice sheet models, our approach was based on empirical information from the real world.

How can real-world ice melt be so much faster than in the ice sheet models that IPCC relies on? Ice sheet modeling is hard. Ice sheet processes occur on spatial scales ranging from microscale freeze-thaw effects that cause pot-holes in our streets to continental-scale “rivers” of ice that discharge icebergs to the ocean. However, as argued in my “slippery slope” paper (Hansen, 2005b), the crucial amplifying feedbacks are probably interactions between ice sheets and oceans abutting against them. Our global climate model results in Ice Melt revealed such specific amplifying feedbacks.

Shutdown of SMOC is a powerful feedback

The shutdown can spur disintegration of the West Antarctic ice sheet (Foreword Figure 2). Our climate model correctly locates deep water formation along the Antarctic coast at places such as the Weddell Sea coast (section 3.8.5 in Ice Melt), which supports use of our model to study the SMOC feedback. That capability is absent in many CMIP (Climate Model Intercomparison Project) models used in the IPCC assessment (Heuze et al., 2015).

SMOC already slowed in our climate simulations by the late 20th century (Foreword Figure 4, which is Fig. 32 in Ice Melt) due to growing freshwater injection from Antarctica. Ocean current measurements are too sparse to accurately monitor SMOC, but sufficient for Purkey and Johnson (2012) to conclude that the real-world SMOC did slow during that period.

SMOC is an escape valve for ocean heat. As relatively warm water reaches the surface near Antarctica (see Foreword Figure 2), heat escapes to the air and space – especially in winter. The salty water cools there to high density and sinks, but as increasing light meltwater is added, the rate of sinking water decreases. As this surface escape valve for heat closes, that heat warms the deeper ocean, with maximum warming at 1-2 km depth. That’s the depth of ice shelf grounding lines, the part of the ice shelf that exerts strongest restraining force on landward ice [Fig. 14 of Jenkins and Doake (1991)]. West Antarctic ice shelves thus have begun to melt more rapidly (Rignot and Jacobs, 2002) and the ice streams feeding them have accelerated (Rignot, 2008).

Menviel et al. (2010) used a simplified Earth system model to show that collapse of the West Antarctic ice sheet would cause expansion of sea ice on the Southern Ocean, suppression of Antarctic Bottom Water formation, and warming of the Southern Ocean at depth. Fogwill et al. (2015) used a high-resolution atmosphere-ocean model to investigate effects of increasing freshwater flux from West Antarctica today, finding that increased ocean stratification reduced bottom water formation and increased ocean temperature at depth. Fogwill et al. submitted their paper on almost the same date in 2015 that we submitted our paper. They concluded, however, that they saw no significant atmospheric response to the freshwater injection. We found a significant accompanying atmospheric feedback.

Precipitation provides an amplifying feedback for sea level rise in our model, but a diminishing feedback in the climate models that IPCC has reported and relied on. Their models yield a large reduction of sea ice around Antarctica and increasing snowfall over the continent as Earth warms. This increased snowfall causes sea level to fall, thus at least partially offsetting sea level rise from ice sheet dynamical mass loss (Foreword Figure 2).

In our climate model described in Ice Melt, increasing meltwater cools the Southern Ocean surface enough to offset greenhouse gas warming. Indeed, the sea surface in the western portion of the Southern Ocean, where two-thirds of increased freshwater injection is occurring (Rignot et al., 2013), already has cooled while the rest of the planet has warmed (Fig. 31 in Ice Melt).

If high fossil fuel emissions continue, SMOC will shut down during the next few decades and sea ice in the Southern Ocean will expand several million square kilometers, according to our climate simulations (Foreword 4b). These effects should begin to emerge this decade from the “noise” level of unforced and unpredictable climate variability.

Before the ink had dried on our Ice Melt paper, Antarctic sea ice cover plummeted (Foreword Figure 4b) to its lowest level in 40 years of satellite data (Parkinson, 2019). Antarctic Bottom Water (AABW) formation – the engine of SMOC – increased (Silvano et al., 2020). So, was the slowdown of SMOC over the prior few decades only temporary? Will Antarctic sea ice decrease now like Arctic sea ice, as predicted by IPCC models?

No, surely not. On the contrary, data that have accumulated since we submitted our paper in 2015 allow improved assessment of the basic time scales of the climate change problem. These time scales are central to our reframing of the ice melt problem and they are at the heart of our disagreement with conclusions of IPCC. One merit of our approach is the role of empirical data, which will allow continual, easily understandable, evaluations as climate response unfolds."
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FishOutofWater

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Re: AMOC (Gulf Stream Current) Collapsing
« Reply #51 on: August 15, 2021, 08:06:18 PM »
Hansen gets it. Figure 2 shows how the AMOC might have a tendency towards episodic warm/cool periods because of Greenland's prograde bed. Surges of meltwater will tend to cause abrupt slow downs and masses of fresh water near Greenland that cause melting to hold back until the cold fresh water is mixed and subducted.

That's what started happening circa 2010 after the first big melt.

The thing is that the subtropical and tropical Atlantic keeps on warming in this episodic slow down scenario.

The Antarctic situation is far more dire because one started the feedback loops accelerate the process. It all has to do with the retrograde bed and the accumulation of ocean heat that keeps on melting the ice from below.

It's a catastrophic instability with very positive feedback loops. The AMOC, at least, has a few regulatory negative feedbacks. Not so the SMOC. It's kind of like a graphite nuclear reactor with positive reactivity.

Have a nice day.

Bruce Steele

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Re: AMOC (Gulf Stream Current) Collapsing
« Reply #52 on: August 15, 2021, 08:44:12 PM »
FIshOutOfWater,  A fairly large chunk of the oceanic carbon sink is carried with the deep water formation processes in the North Atlantic. It would seem that the ocean carbon sink would wax and wane with the strength of the AMOC. How come we don’t see any such cycle in the Mona Loa data ?
 So when the AMOC is weak more CO2 should stay in the atmosphere and when it is strong more CO2 would be carried to depth.
 If the Southern Ocean Bottom Water formation is weak the same time as the AMOC gets weak then I can’t see how the ocean carbon sink apparently continues apace.

FishOutofWater

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Re: AMOC (Gulf Stream Current) Collapsing
« Reply #53 on: August 15, 2021, 10:16:55 PM »
The AMOC slowdowns occur over multiyear episodes and do not involve all of the regions involved in the AMOC at once. In fact, the subtropical Atlantic kept on taking up heat and CO2 in both hemispheres while the cold pool was present in the far north Atlantic after the massive Arctic fresh water dump that went from 2012 to 2016.

There are so many other things going on that we can't break out the impact of the AMOC slowdown in the Mauna Loa data, but it's probably in there.

AbruptSLR

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Re: AMOC (Gulf Stream Current) Collapsing
« Reply #54 on: August 16, 2021, 03:00:11 AM »
...
 If the Southern Ocean Bottom Water formation is weak the same time as the AMOC gets weak then I can’t see how the ocean carbon sink apparently continues apace.

The linked article (& associated linked reference) indicates that low salinity in Southern Ocean surface waters reduces its ability to serve as a carbon sink.  Thus, if the WAIS were to lose significant ice mass in the coming decades (as projected by Hansen but not by consensus climate scientists) then this would freshen the Southern Ocean surface waters and thus would reduce carbon sequestration beyond that indicated by the linked article/reference.

Title: "Uncertainty of future Southern Ocean CO2 uptake cut in half"

https://www.sciencedaily.com/releases/2021/04/210428140855.htm

Extract: "The Southern Ocean -- the world's largest ocean sink region for human-made CO2 -- is projected to absorb a total of about 244 billion tons of human-made carbon from the atmosphere over the period from 1850 to 2100 under a high CO2 emissions scenario. But the uptake could possibly be only 204 or up to 309 billion tons. That's how much the projections of the current generation of climate models vary. The reason for this large uncertainty is the complex circulation of the Southern Ocean, which is difficult to correctly represent in climate models.

In their study, the three climate scientists show why the salinity content of the ocean surface waters is a good indicator of how much human-made CO2 is transported into the ocean interior. Models that simulate low salinity in the Southern Ocean surface waters have too light waters and therefore transport less water and CO2 into the ocean interior. As a result, they also absorb less CO2 from the atmosphere. Models with higher salinity, on the other hand, show higher absorption of CO2 from the atmosphere. The salinity of the Southern Ocean surface waters, determined through observations, allowed the researchers from Bern to narrow down the uncertainty in the various model projections."

See also:

Jens Terhaar, Thomas L. Frölicher, Fortunat Joos. Southern Ocean anthropogenic carbon sink constrained by sea surface salinity. Science Advances, 2021; 7 (18): eabd5964 DOI: 10.1126/sciadv.abd5964

https://advances.sciencemag.org/content/7/18/eabd5964

Abstract: "The ocean attenuates global warming by taking up about one quarter of global anthropogenic carbon emissions. Around 40% of this carbon sink is located in the Southern Ocean. However, Earth system models struggle to reproduce the Southern Ocean circulation and carbon fluxes. We identify a tight relationship across two multimodel ensembles between present-day sea surface salinity in the subtropical-polar frontal zone and the anthropogenic carbon sink in the Southern Ocean. Observations and model results constrain the cumulative Southern Ocean sink over 1850-2100 to 158 ± 6 petagrams of carbon under the low-emissions scenario Shared Socioeconomic Pathway 1-2.6 (SSP1-2.6) and to 279 ± 14 petagrams of carbon under the high-emissions scenario SSP5-8.5. The constrained anthropogenic carbon sink is 14 to 18% larger and 46 to 54% less uncertain than estimated by the unconstrained estimates. The identified constraint demonstrates the importance of the freshwater cycle for the Southern Ocean circulation and carbon cycle."

Edit: The attached image shows one the observed sea surface salinity trend distribution in one part of the Southern Ocean showing the impact of recent meltwater (primarily to date from ice shelves [see the second image] and sea ice melting [see the third image]) and precipitation.
« Last Edit: August 16, 2021, 04:57:16 PM by AbruptSLR »
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AbruptSLR

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Re: AMOC (Gulf Stream Current) Collapsing
« Reply #55 on: August 16, 2021, 04:54:45 PM »
...
The Antarctic situation is far more dire because one started the feedback loops accelerate the process. It all has to do with the retrograde bed and the accumulation of ocean heat that keeps on melting the ice from below.

It's a catastrophic instability with very positive feedback loops. The AMOC, at least, has a few regulatory negative feedbacks. Not so the SMOC. It's kind of like a graphite nuclear reactor with positive reactivity.

Have a nice day.

The first image shows that currently there are four regions of AABW formation (which drives the SMOC shown in the second image), with the Ross Sea region AABW production leading to meridional overturning circulation (MOC) to the Pacific Ocean, the Weddell Sea region leading to MOC leading to the Atlantic Ocean and both the Aurora Subglacial Basin and the Amery basin leading to MOC to the Indian Ocean.  Furthermore, I single-out the MOC leading to the Tropical Pacific as the accelerating evaporation from the Tropical Pacific surface waters as the SST increases (including due to the slowing of the MOC) drives many telecommunications (see the third image of the atmospheric telecommunication from the Tropical Pacific to the Southeastern Bering Sea region) that influence various Earth Systems (see the fourth image that shows how warm air/evaporation migrating from the both Tropical Pacific to the Southeastern Bering Sea area, and from the Tropical Atlantic, impacts the Arctic jet stream).
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jai mitchell

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Re: AMOC (Gulf Stream Current) Collapsing
« Reply #56 on: August 16, 2021, 07:38:34 PM »
FIshOutOfWater,  A fairly large chunk of the oceanic carbon sink is carried with the deep water formation processes in the North Atlantic. It would seem that the ocean carbon sink would wax and wane with the strength of the AMOC. How come we don’t see any such cycle in the Mona Loa data ?
 So when the AMOC is weak more CO2 should stay in the atmosphere and when it is strong more CO2 would be carried to depth.
 If the Southern Ocean Bottom Water formation is weak the same time as the AMOC gets weak then I can’t see how the ocean carbon sink apparently continues apace.

Bruce,

I have seen an unverified quote that the AMOC represents about 0.7 Pg of carbon sequestration.  As you can see from ASLRs picture above, the variability went from a high of 17 Sv to a low of 16 Sv so the amount of change in ocean carbon sequestration isn't really noticeable there, compared to other fluctuations associated with ENSO and emissions, fire feedbacks, etc.
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vox_mundi

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Re: AMOC (Gulf Stream Current) Collapsing
« Reply #57 on: June 07, 2022, 04:43:00 PM »
A huge Atlantic ocean current is slowing down—if it collapses, La Niña could become the norm for Australia
https://phys.org/news/2022-06-huge-atlantic-ocean-current-downif.html



... In our study, we used a comprehensive global model to examine what Earth's climate would look like under such a collapse. We switched the Atlantic overturning off by applying a massive meltwater anomaly to the North Atlantic, and then compared this to an equivalent run with no meltwater applied.

Our focus was to look beyond the well-known regional impacts around Europe and North America, and to check how Earth's climate would change in remote locations, as far south as Antarctica.

The first thing the model simulations revealed was that without the Atlantic overturning, a massive pile up of heat builds up just south of the Equator.

This excess of tropical Atlantic heat pushes more warm moist air into the upper troposphere (around 10 kilometres into the atmosphere), causing dry air to descend over the east Pacific.

The descending air then strengthens trade winds, which pushes warm water towards the Indonesian seas. And this helps put the tropical Pacific into a La Niña-like state.

Australians may think of La Niña summers as cool and wet. But under the long-term warming trend of climate change, their worst impacts will be flooding rain, especially over the east.



We also show an Atlantic overturning shutdown would be felt as far south as Antarctica. Rising warm air over the West Pacific would trigger wind changes that propagate south to Antarctica. This would deepen the atmospheric low pressure system over the Amundsen Sea, which sits off west Antarctica.

This low pressure system is known to influence ice sheet and ice shelf melt, as well as ocean circulation and sea-ice extent as far west as the Ross Sea.



Bryam Orihuela-Pinto et al, Interbasin and interhemispheric impacts of a collapsed Atlantic Overturning Circulation, Nature Climate Change (2022)
https://www.nature.com/articles/s41558-022-01380-y

« Last Edit: June 07, 2022, 04:48:04 PM by vox_mundi »
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Re: AMOC (Gulf Stream Current) Collapsing
« Reply #58 on: June 07, 2022, 09:58:47 PM »
A huge Atlantic ocean current is slowing down—if it collapses, La Niña could become the norm for Australia
Sounds like good news for Australia. More water can be easily drained with new rivers, or canals. Europeans and Californians can all move there...  ::)

I'm still wondering if a slowdown of the AMOC is causing more water to flow through the Bering strait... Less water through the Atlantic frontdoor should open up the backdoor for more and warmer Pacific water through the Bering strait, no? Or would the change in air pressure that those images you posted show counteract this?
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Rodius

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Re: AMOC (Gulf Stream Current) Collapsing
« Reply #59 on: June 08, 2022, 12:34:33 PM »
A huge Atlantic ocean current is slowing down—if it collapses, La Niña could become the norm for Australia
Sounds like good news for Australia. More water can be easily drained with new rivers, or canals. Europeans and Californians can all move there...  ::)

I'm still wondering if a slowdown of the AMOC is causing more water to flow through the Bering strait... Less water through the Atlantic frontdoor should open up the backdoor for more and warmer Pacific water through the Bering strait, no? Or would the change in air pressure that those images you posted show counteract this?

Not really good news.... what it means is regular massive flooding events that removes top soil (which is already depleted).

It is difficult to comprehend the size of the flooding events in Australia, but the easiest way to think about it is to imagine flood waters that are the size of England happening several times a year.

Queensland has had two similarly sized flooding events this year and both were in about the same place.

Permanent La Nina conditions would be a disaster for Australia.

vox_mundi

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Re: AMOC (Gulf Stream Current) Collapsing
« Reply #60 on: June 08, 2022, 12:51:16 PM »
It also means increased hurricanes on the US East & Gulf coasts
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Re: AMOC (Gulf Stream Current) Collapsing
« Reply #61 on: June 08, 2022, 01:13:56 PM »
A huge Atlantic ocean current is slowing down—if it collapses, La Niña could become the norm for Australia
Sounds like good news for Australia. More water can be easily drained with new rivers, or canals. Europeans and Californians can all move there...  ::)

I'm still wondering if a slowdown of the AMOC is causing more water to flow through the Bering strait... Less water through the Atlantic frontdoor should open up the backdoor for more and warmer Pacific water through the Bering strait, no? Or would the change in air pressure that those images you posted show counteract this?

Not really good news.... what it means is regular massive flooding events that removes top soil (which is already depleted).

It is difficult to comprehend the size of the flooding events in Australia, but the easiest way to think about it is to imagine flood waters that are the size of England happening several times a year.

Queensland has had two similarly sized flooding events this year and both were in about the same place.

Permanent La Nina conditions would be a disaster for Australia.
I understand it is a disaster right now, because the natural environment in Australia isn't able to deal with all that water, but wouldn't the environment change if it would become an annual occurrence? Wouldn't more vegetation start to grow in those wetter conditions that would start to hold the topsoil in place? Or would that new vegetation never get a chance to grow big enough?

I'm thinking about other regions in the world with lots of rain. They can handle it, so wouldn't Australia eventually be able to handle it as well? I'm sure that'll take a long time, but nature finds a way, no? Water is life, right?
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Re: AMOC (Gulf Stream Current) Collapsing
« Reply #62 on: June 08, 2022, 01:53:58 PM »
1200 mm of rain evenly distributed over 12 months is great for plants; 600 mm in one week followed by 4 months of drought - not so much.  :-\
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Re: AMOC (Gulf Stream Current) Collapsing
« Reply #63 on: June 08, 2022, 02:26:51 PM »
1200 mm of rain evenly distributed over 12 months is great for plants; 600 mm in one week followed by 4 months of drought - not so much.  :-\
That may indeed be a problem...  :-\
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Re: AMOC (Gulf Stream Current) Collapsing
« Reply #64 on: June 08, 2022, 03:02:31 PM »
"I understand it is a disaster right now, because the natural environment in Australia isn't able to deal with all that water, but wouldn't the environment change if it would become an annual occurrence? Wouldn't more vegetation start to grow in those wetter conditions that would start to hold the topsoil in place? Or would that new vegetation never get a chance to grow big enough?"
When I was in Aus. I read about a riverboat that got lost in a flood, iirc it plied it's trade from the south coast up into the north, the rains were so heavy the captain lost his bearings, eventually the boat grounded and the crew and passengers had to walk out.The boat was lost for years until one day someone came across it about 80miles from the river. When these floods occur, again iirc, the desert blooms even frogs emerge from their caked mud cocoons, then the flood subsides.

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Re: AMOC (Gulf Stream Current) Collapsing
« Reply #65 on: June 09, 2022, 07:55:13 AM »
1200 mm of rain evenly distributed over 12 months is great for plants; 600 mm in one week followed by 4 months of drought - not so much.  :-\
That may indeed be a problem...  :-\

That is the problem.

Floods remove topsoil, they devastate everything, and while the local wildlife has dealt with this before, it hasnt and wont be able to adapt to far more frequent rain events.

And it isnt just nature, entire towns have been badly flooded, some twice in one year. People are sick of the floods coming through (one town, the house are lifted 2 meters up on stilts to avoid floods that are 1 in 100 year events, but there have been 3 of them in 5 years that have exceeded the 2-meter lifting.) that they are basically leaving the region so they dont have to do it again in a few years.

And forget about getting insurance, they have effectively said some regions in Australia are uninsurable now.

And that is just from the regions that get floods that are inland.

Combine that with the, ironically, longer and drier droughts, and you see farmers walking away from the land, fires becoming bigger (another irony of water in Australia is wet years means great growth that dries out within 5 months during summer which becomes fuel for fires in the summer)... the changes in climate here are not good at all... and if La Nina somehow does become more common, and when combined with more extreme El Nino events, well, it is just bad news everywhere.

I am dreading the next El Nino, those fires a few years ago, aptly called the Black Summer, happened in a neutral year. The conditions of that summer was more like a bad EL Nino event. I am truly dreading the next El Nino, I can see the fires being far bigger and more devastating than the Black Summer.

To me, barring the part when things are going to get worse, it is too difficult to figure out exactly how the difficulties will present or when they will monster us.
Australia is not a good place to be in terms of climate change, even if we have more La Nina events moving forward.

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Re: AMOC (Gulf Stream Current) Collapsing
« Reply #66 on: June 09, 2022, 08:09:44 AM »
1200 mm of rain evenly distributed over 12 months is great for plants; 600 mm in one week followed by 4 months of drought - not so much.  :-\
That may indeed be a problem...  :-\

That is the problem.

Floods remove topsoil, they devastate everything, and while the local wildlife has dealt with this before, it hasnt and wont be able to adapt to far more frequent rain events.

And it isnt just nature, entire towns have been badly flooded, some twice in one year. People are sick of the floods coming through (one town, the house are lifted 2 meters up on stilts to avoid floods that are 1 in 100 year events, but there have been 3 of them in 5 years that have exceeded the 2-meter lifting.) that they are basically leaving the region so they dont have to do it again in a few years.

And forget about getting insurance, they have effectively said some regions in Australia are uninsurable now.

And that is just from the regions that get floods that are inland.

Combine that with the, ironically, longer and drier droughts, and you see farmers walking away from the land, fires becoming bigger (another irony of water in Australia is wet years means great growth that dries out within 5 months during summer which becomes fuel for fires in the summer)... the changes in climate here are not good at all... and if La Nina somehow does become more common, and when combined with more extreme El Nino events, well, it is just bad news everywhere.

I am dreading the next El Nino, those fires a few years ago, aptly called the Black Summer, happened in a neutral year. The conditions of that summer was more like a bad EL Nino event. I am truly dreading the next El Nino, I can see the fires being far bigger and more devastating than the Black Summer.

To me, barring the part when things are going to get worse, it is too difficult to figure out exactly how the difficulties will present or when they will monster us.
Australia is not a good place to be in terms of climate change, even if we have more La Nina events moving forward.
I should probably not react now while I'm reaching the bottom of a bottle of whiskey....
I feel your pain... It's not your fault... But can you understand the irony?
Are the Aussies awake now about climate change? Or do they still want to dig up more coal?
90% of the world is religious, but somehow "love thy neighbour" became "fuck thy neighbours", if they don't agree with your point of view.

WTF happened?

Rodius

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Re: AMOC (Gulf Stream Current) Collapsing
« Reply #67 on: June 09, 2022, 02:34:17 PM »
1200 mm of rain evenly distributed over 12 months is great for plants; 600 mm in one week followed by 4 months of drought - not so much.  :-\
That may indeed be a problem...  :-\

That is the problem.

Floods remove topsoil, they devastate everything, and while the local wildlife has dealt with this before, it hasnt and wont be able to adapt to far more frequent rain events.

And it isnt just nature, entire towns have been badly flooded, some twice in one year. People are sick of the floods coming through (one town, the house are lifted 2 meters up on stilts to avoid floods that are 1 in 100 year events, but there have been 3 of them in 5 years that have exceeded the 2-meter lifting.) that they are basically leaving the region so they dont have to do it again in a few years.

And forget about getting insurance, they have effectively said some regions in Australia are uninsurable now.

And that is just from the regions that get floods that are inland.

Combine that with the, ironically, longer and drier droughts, and you see farmers walking away from the land, fires becoming bigger (another irony of water in Australia is wet years means great growth that dries out within 5 months during summer which becomes fuel for fires in the summer)... the changes in climate here are not good at all... and if La Nina somehow does become more common, and when combined with more extreme El Nino events, well, it is just bad news everywhere.

I am dreading the next El Nino, those fires a few years ago, aptly called the Black Summer, happened in a neutral year. The conditions of that summer was more like a bad EL Nino event. I am truly dreading the next El Nino, I can see the fires being far bigger and more devastating than the Black Summer.

To me, barring the part when things are going to get worse, it is too difficult to figure out exactly how the difficulties will present or when they will monster us.
Australia is not a good place to be in terms of climate change, even if we have more La Nina events moving forward.
I should probably not react now while I'm reaching the bottom of a bottle of whiskey....
I feel your pain... It's not your fault... But can you understand the irony?
Are the Aussies awake now about climate change? Or do they still want to dig up more coal?

People want to believe they understand, but not enough to take the action required to stop it.

Politics, while improving, still prefers coal and gas.....

Probably best to get back on topic though.