The Climatic Effects of a Blue Ocean Event

[rboyd]

I have been finding it difficult to find information on the wider global impacts of a Blue Ocean Event, outside the likes of Paul Beckwith. Peter Wadhams and an odd few extremely reticent/conservative academic papers. Hopefully this topic will help bring together what knowledge there is. Impacts from the materials that I have been able to find have included:

- A collapse of the polar cell and ferrel cells with a resulting equible Northern Hemisphere climate
- A "polar cell" centred on Greenland (until that melts out) with very static jet streams and little seasonal variability
- A maritime environment in the Arctic that produces large precipitation on permafrost areas, which will then accelerate CO2/CH4 emissions
- Massive storms in the North Atlantic as the more rapid melting of Greenland creates a bigger, more intense, "cold blob" that contrasts with the warmer waters around it
- A general acceleration of climate change due to much lower Northern Hemisphere reflectivity
- More rapid melting of the Antarctic due to the climate "see-saw"
- Northward movement of the ITCZ rain belts greatly changing rainfall patterns (plus and minus) for some areas
- etc.

This is a paper I wrote on the subject a couple of years ago and its amazing how little research has been published in the interim.

https://www.resilience.org/stories/2017-06-21/the-impacts-of-an-ice-free-arctic-a-climate-paradigm-shift/

Seems to generally be "the Northern Hemisphere is f***ed" with a BOE. I have started looking at real estate in Ecuador (Cuenca seems to be very nice) and the Paraguay highlands! Others insights would be much appreciated.

[dollarbillronson]

Thank you for this thread.

I will take the liberty to quote a reddit post I have saved which reflects on the matter, by user "Athrowawayinmay" however judging by his nickname I suspect he is not that keen on receiving credit for it. Anyway, it may be less scientific than your conclusions but surely would be able to explain in layman's terms what would happen when a BOE nears/happens:

The arctic ice does many very important things, that by melting away will cause a lot of problems (just from the top of my head I'll list some below). The total loss of arctic ice is called "The Blue Ocean Event" (if you were looking to read up more on it), and it is something that should be happening in the next 2 to 10 years after which there will be some severe consequences.

-    It has a stabilizing effect on the jet stream which leads to stable, consistent and non-extreme weather. No arctic buffer leads to extreme weather.

-   The annual melt of arctic ice also provides fresh water for a lot of areas. No more ice means no more ice melt means no more water.

-   Too much ice melt means fresh cold water entering the ocean. This can lead to the collapse of the ocean currents. These same currents are what allows the UK isles to be inhabitable (they'd be MUCH colder without the warm ocean currents).

-  The arctic is the literal home for certain animals (polar bears). No ice, no ground, no home.

-  The arctic ice, being white, acts as a great big reflector of sunlight and heat. That's gone, and we get warmer faster.

-  The arctic ice, being a giant block of ice, acts as a buffer for heat. Energy that used to go into melting ice now contributes directly to land/air temperatures (think of a cup of ice water, your cup of water doesn't get warm until the ice melts; same concept).

-  There are a lot of things currently frozen in the "perma-frost" (that won't be so permanently frozen anymore). There's something called the "Clathrate gun hypothesis" that essentially when the greenhouse gases frozen up north melt and enter the air global warming will drastically accelerate and be truly unstoppable.

[Pragma]

Roger,

I think you have produced a pretty complete laundry list. One could add on knock-on effects like crop loss, but that could go on forever, and we don't even fully understand the current climate situation, let alone what we may be facing.

In your paper, I do have a minor quibble about IPCC carbon budgets, in that any that are based in some kind of reality all involve negative carbon. So, to me the issue is moot, although I think the entire IPCC is moot.

I've been thinking about this lately, along with many other here, I'm sure. Relatively speaking, it's imminent.

As has been said, a BOE is not a magic event and the significance will vary as it happens earlier and earlier in the season. That said, I think it is already happening but we haven't changed things that much, yet. (let me explain  )

Although we have reduced volume significantly, we have not reduced area anywhere near as much. We are not nearly as far along as some would assume, but area will catch up very quickly IMHO.

So, what we are seeing in terms of jet stream incoherence and other effects is just a taste of what is to come.

As usual, it all comes down to how soon will it happen and how fast we will see the effects?

Everything seems to be "sooner than expected" and "faster than expected".

[pietkuip]

I find it hard to imagine a polar cell centered on Greenland. I am not a meteorologist but the Earth's rotation is around the pole and this does not look like a stable solution (Coriolis forces).

Jennifer Francis has a few talks on Youtube. I watch Paul Beckwith too but Francis is much more an authority on this. Her expectation is that the distribution of land masses and seas and ice sheets around the pole might lock the Rossby waves.

[rboyd]

In your paper, I do have a minor quibble about IPCC carbon budgets, in that any that are based in some kind of reality all involve negative carbon. So, to me the issue is moot, although I think the entire IPCC is moot.

I tend to now treat the IPCC reports as "soft denial", making greater and greater modelling assumptions (such as NETs) to match reality with ongoing economic growth. We blew the carbon budget a good few years ago.

[rboyd]

I find it hard to imagine a polar cell centered on Greenland. I am not a meteorologist but the Earth's rotation is around the pole and this does not look like a stable solution (Coriolis forces).

Jennifer Francis has a few talks on Youtube. I watch Paul Beckwith too but Francis is much more an authority on this. Her expectation is that the distribution of land masses and seas and ice sheets around the pole might lock the Rossby waves.

I watch Paul but do tend to check some of his statements, thanks for the input on the Greenland "cole pole" proposal. Used to keep up with Jennifer Francis' work, will have to look for some recent videos.

[GoSouthYoungins]

First of all: THANK YOU rboyd. Super smart topic/thread. Exceedingly interesting and surprisingly little discussion and almost no serious science looking into the issue. (Probably because it is so bizarre and such an unstable state in medium to long-term, but not in terms of a human lifespan.)

Her expectation is that the distribution of land masses and seas and ice sheets around the pole might lock the Rossby waves.

This seems to make sense to me. However, I don't think the Jet Stream would be permanently locked into place. I think it would go through at least 2 phases. The zero insolation vs highest-on-earth insolation switch that happens annually in the arctic seems like it would have to shift the system dynamics.

[Tony Mcleod]

First of all: THANK YOU rboyd. Super smart topic/thread. Exceedingly interesting and surprisingly little discussion and almost no serious science looking into the issue. (Probably because it is so bizarre and such an unstable state in medium to long-term, but not in terms of a human lifespan.)

Totally agree.  It seems to me a boe/new cold pole is one of the main stepping stones towards climate chaos, especially for the NH. If the 'cold pole' translates that far off centre it surely will cause drastic changes in the position and stability of the polar jet. Not being a meteorologist I can't even imagine how that will affect blocking patterns, the stability of the jet or even the existence of the atmospheric cells.
If there are changes remotely like these then a large percentage of the earth's population are going to be in dire trouble as far as their expected rainfail goes.

[Archimid]

Thank you for this thread rboyd. It is needed.

I have been finding it difficult to find information on the wider global impacts of a Blue Ocean Event,

Me too. Most I find tells me to not worry about it because a BOE will be like Tuesday. Everything will work just like before sans ice on top. Fish will get fat, shipping lanes will open. Sure Eskimos will have to end their lifestyle but Siberia will be the next Europe and Russia will be great again. Polar bears that stick to the coast will be just fine.

Because of this our risk assessment of a BOE is completely wrong.

A collapse of the polar cell and ferrel cells with a resulting equible Northern Hemisphere climate

The problem is not an equable climate. I don't believe the planet is hot enough for that yet. The problem is the transition to an equable climate, which has already begun.

Climate patterns that held for millennia are now shifting to match the new temperature difference.  Global warming is worse for the changes in temperature differences between the equator and the North Pole than the rise in temperatures.

[dnem]

I think we need some clarity here on what we mean by a BOE.  Personally, I think that one of these years before 2025 we will dip below 1 mil km² in September, and then, despite a slow start to the freeze season, we will get a reasonable freeze-up and then the need for another strong melt season the next year to get back to a late season BOE.  I don't think the occasional late season sub 1 million km² extent will have a dramatic, chaotic effect on NH weather.  When we start having long months of peak insolation falling on a mostly ice free arctic, then we might well have dramatic impacts.

To me a very key question is how long it will take to transition from a BOE just being an occasional thing like a 2007 or 2012 to being a months long phenomenon every summer.

[GoSouthYoungins]

Thank you for this thread rboyd. It is needed.

I have been finding it difficult to find information on the wider global impacts of a Blue Ocean Event,

Me too. Most I find tells me to not worry about it because a BOE will be like Tuesday. Everything will work just like before sans ice on top. Fish will get fat, shipping lanes will open. Sure Eskimos will have to end their lifestyle but Siberia will be the next Europe and Russia will be great again. Polar bears that stick to the coast will be just fine.

Because of this our risk assessment of a BOE is completely wrong.

A collapse of the polar cell and ferrel cells with a resulting equible Northern Hemisphere climate

The problem is not an equable climate. I don't believe the planet is hot enough for that yet. The problem is the transition to an equable climate, which has already begun.

Climate patterns that held for millennia are now shifting to match the new temperature difference.  Global warming is worse for the changes in temperature differences between the equator and the North Pole than the rise in temperatures.

Woah. I agree with everything you just said. Woah.

[nanning]

Woah. I agree with everything you just said. Woah.

Me too.

[DaveHitz]

Based on no actual data, I wonder whether there might be two forms of BOE.

(1) Some radical change throws the arctic into a very different mode than anything we've seen. For example, what if the halocline collapsed, melting the CAB surprisingly quickly. That might jar the CAB into a new state that replaces the old state.

(2) The melt slowly increases, each year a bit more than the last, until hitting the BOE limit occurs regularly, maybe not every year but every few, but then things mostly freeze up again after. This second case seems to be the more common prediction around here. That is, the BOE is a low-drama event where the ice happens to cross an arbitrary limit, but it doesn't radically shake our world.

Here's my point. My hunch is that the first style would have a larger effect on climate than the second. So to really talk about what effect a BOE might have, we need to think about what time of BOE we are considering.

[petm]

@DaveHitz: I think #1 and tied to a transition to equable climate.

Speaking of which, the big question is: for the transition to equable, how fast is fast? It seems like we don't know, and instead of happening over 10,000s of years as previously assumed, it could even be more like decades. https://history.aip.org/climate/rapid.htm .

It seems to me that the assumption of stability is more a product of human psychology than evidence / external reality (similarly, https://en.wikipedia.org/wiki/Illusion_of_control). For instance, the analogous and closely related assumption of gradual evolution of species has already been challenged (in my view successfully) -- https://en.wikipedia.org/wiki/Punctuated_equilibrium.

And in the field of climate change, which is tellingly itself rapidly changing, all of the advances seem to point in the same direction: far more rapid change than previously imagined (https://en.wikipedia.org/wiki/Failure_of_imagination); for instance, transient major accelerations in the flow of ice sheets during the (ever expanding) melt season due to basal injections of surface meltwater  (https://science.sciencemag.org/content/297/5579/218.short).

"In general, a direct coupling between increased surface melting and ice-sheet flow has been given little or no consideration in estimates of ice sheet response to climate change." (2002, above)

Similarly, the relationship between warming oceans and the previously unimagined rapid retreat of marine terminating glaciers is just starting to be understood (https://www.nature.com/articles/ncomms9566).

Seems to me that it's all up for grabs...

[Tony Mcleod]

There maybe links to this elsewhere but this Just Have a Think episode on BOE, linked below, provides some relevent material.

[Klondike Kat]

The consequences of a BOE depend largely on the length of such an event.  Some have suggested that shortly after the first summer BOE event that the entire Arctic will spiral towards a year-round BOE.  That appears unlikely, which I will explain later.  But, lets us assume for arguments sake that a year-round BOE follows shortly after the first summertime BOE.  One of the biggest effects of a BOE is the albedo effect; the loss of ice, replace by open water, will lead to a substantially reduced albedo, which will cause the Arctic ocean to absorb significantly more heat.  The warming oceans will accelerate the ice loss.  The warming Arctic would lead to a decreased mid-latitude to pole difference, causing the polar jet stream to slow and meander southward.  This will bring colder Arctic air southward and warmer mid-latitude air northward, further amplifying this effect.  The result is cooler mid-latitude summers, warmer high-latitude summers, and increased rainfall throughout.  This is similar to what has occurred recently.

If the BOE were to persist throughout the Arctic winter, then a comparable amount of heat would be lost during the cold, dark months, due to the lack of ice cover.  This could exceed the heat gain, as the Arctic winter tends to have less cloud cover than the Arctic summer.  The Arctic temperature will drop rapidly, resulting in a greater mid-latitude to pole temperature gradient.  This will cause the polar stream to accelerate, tightening its rotation about the pole.  This will lead to warmer mid-latitude winters and colder Arctic winters.  This has not occurred in recently years, as both have warmed.

Consequently, a summer BOE is highly unlikely to result in a year-round BOE, as the large heat loss that would occur during an Arctic winter, would cause the temperature to fall significantly below freezing.  However, a year-long BOE might be preferable to a seasonal BOE, as it would allow substantial heat to be lost, slowing the global temperature rise.

[El Cid]

A BOE is nothing special. We are already experiencieng BOE of the Barents, BOE of the Bering, etc. As time passes by, we will experience a BOE of the CAB eventually. Since we have already experienced partial/small BOEs, we know exactly what it brings (see pic) in the NH midlatitudes: much warmer winters, especially in Eurasia, due to the weakening of the Siberian High; and warmer summers. That's it. There is nothing mystical about the BOE. And more rain of course, but that is obvious

[Rich]

Not an expert here, but I've watched some Jennifer Francis YouTube videos ;-).

As the Arctic warms, the temperature gradient between the pole and mid-latitude declines and weakens the polar cell and jet stream.

The CAB still provides a lot of cooling to maintain that gradient even though it is has certainly weakened so far.

I think the continuing loss of ice means increasing weather chaos as the wind circulation patterns decay.

BOE also represents phase change as hear currently allocated to melting ice is no longer used for that purpose. It becomes completely available for warming. As El Cid points out, that is already happening in peripheral seas. But that peripheral sea heat is spreading out to the CAB where it encounters and melts ice. I don't think we're truly seeing the full BOE effect in peripheral seas yet when there is still adjacent CAB ice to be melted.

I see a BOE in the CAB as a positive feedback event. But I'm not an expert.

[Burnrate]

A BOE is nothing special. We are already experiencieng BOE of the Barents, BOE of the Bering, etc. As time passes by, we will experience a BOE of the CAB eventually. Since we have already experienced partial/small BOEs, we know exactly what it brings (see pic) in the NH midlatitudes: much warmer winters, especially in Eurasia, due to the weakening of the Siberian High; and warmer summers. That's it. There is nothing mystical about the BOE. And more rain of course, but that is obvious

This is all completely wrong.

[Gray-Wolf]

Any BOE will allow 'normal ocean processes' to resume across the Arctic Ocean with the total loss of the Halocline as swell/waves mix out the remaining areas of deep Halocline that used to aid the Ocean in re-freeze/ice retention.

There is already plenty of heat in the basin to enable year round ice free but the Halocline places a barrier between the surface and that heat.

With the last of the Halocline washed out what is to stop further mixing of the ocean's stratification?

And what of the thickness of the atmosphere above the basin?

Do we see that thicken and so allow more lightning inside the high Arctic? With most of the wildfires being started by lightning such an uptick will surely increase these events too?

[Rich]

Personally, I think that one of these years before 2025 we will dip below 1 mil km

I'm curious where the 2025 comes from.  It seems like the ASIF community is more bearish than the scientists.

We've only had one year below 4M km2 so far. Maybe this year will be the 2nd. But that's an extraordinary leap you're projecting. A system change cliff.

 

[SteveMDFP]

If the BOE were to persist throughout the Arctic winter, then a comparable amount of heat would be lost during the cold, dark months, due to the lack of ice cover.  This could exceed the heat gain, as the Arctic winter tends to have less cloud cover than the Arctic summer.   

This may be a little simplistic.  Open ocean with frigid air above produces dense fog and clouds, with a substantial insulating effect.  Remember that Ellesmere island used to be home to alligators, long ago.  It's an open question as to how soon such a climate could resume there, with our atmosphere rapidly increasing in greenhouse gases:

How giant tortoises, alligators thrived in High Arctic 50 million years ago
https://www.sciencedaily.com/releases/2010/08/100824132417.htm

[Midnightsun]

I live above 60N and the changes are already very noticeable.

The problem with the jet stream is not when it becomes slower and wider, the problem is that it becomes like a flower and that creates all kinds of weird and extreme weather - and it has done so already. 2018 the UK got "vortex'd" in springtime, this year it was the US.

The river of hail in Mexico and the killer 'nado in Greece happened at the same time as kink in the jet stream were positioned directly above them.

I don't understand why people think BOE is not a big deal since our entire civilization depends on the stability (that used to be) brought by the jet streams.

[Burnrate]

I have read that the US east coast sea level is rising significantly faster than the global average (1 inch per year) due to the slowdown of the gulf stream (among other things).

I wonder how much a BOE would increase the melting speed of Greenland which would cause the gulf stream to slow down even more.  I imagine relatively warm waters surrounding Greenland and the instability of the jet stream could cause some pretty extreme and rapid melting (even more so than it already does).  All that fresh, cold water would continue to slow the AMOC.  Seeing more than an inch per year of sea level rise on the US east coast would be pretty intense.  Of course that average number doesn't even represent the extremes that would occur at high tides.

Anyone read anything specifically about the BOE's effect on Greenland's melting rate?

[El Cid]

A BOE is nothing special. We are already experiencieng BOE of the Barents, BOE of the Bering, etc. As time passes by, we will experience a BOE of the CAB eventually. Since we have already experienced partial/small BOEs, we know exactly what it brings (see pic) in the NH midlatitudes: much warmer winters, especially in Eurasia, due to the weakening of the Siberian High; and warmer summers. That's it. There is nothing mystical about the BOE. And more rain of course, but that is obvious

This is all completely wrong.

Nice argument, great facts!

[Bruce Steele]

At some point the Beaufort Gyre will reverse and a very large amount of surface fresh water , similar to the amount of fresh water in the Great Lakes, will head to the Atlantic. This will allow the Pacific Warm Water layer to rise from its current depth and depending on how long the reversal lasts some of the Pacific Warm Water will spill out onto the coastal shelfs where it can mix with what is left of the surface fresh water. The increased heat and salinity that mixes with the surface waters will accelerate bottom melt on any ice it encounters.
 So the changes in the halocline that Gray-Wolf describes would be much enhanced if a reversal and a very low level of sea ice were to happen at the same time.
 The cold fresh water that would make its way to the North Atlantic would cause a slowdown in the MOC and cause a cooling of weather conditions for Europe and Greenland . The Beaufort would resume it's clockwise spin and subsequent freeze thaw seasons and flow from the Mckenzie River would restore the surface fresh water in the Gyre. Warm ice free surface water conditions in the Beaufort may give a boost to high pressure weather systems that can reverse the Gyre. A reversal in the late summer could help spread heat to the remaining ice in the CAB and contribute to our first BOE.
 The resulting cold in the North Atlantic may contribute to several rebound years in Arctic sea ice conditions . So although a disruption of the halocline would cause all sorts of havoc in the year it happens I think the Arctic would return to stratified conditions within a year and that the Arctic Sea Ice might even regain thickness/ strength has a result of resulting North Atlantic conditions.
 

[Burnrate]

At some point the Beaufort Gyre will reverse and a very large amount of surface fresh water , similar to the amount of fresh water in the Great Lakes, will head to the Atlantic. ...

So not just Greenland ice melt slowing down the AMOC.  That is crazy.  Stall out the current for a bit and get a few feet of sea level rise on the US east coast in a year or two.

[rboyd]

If the BOE were to persist throughout the Arctic winter, then a comparable amount of heat would be lost during the cold, dark months, due to the lack of ice cover.  This could exceed the heat gain, as the Arctic winter tends to have less cloud cover than the Arctic summer.  The Arctic temperature will drop rapidly, resulting in a greater mid-latitude to pole temperature gradient.  This will cause the polar stream to accelerate, tightening its rotation about the pole.  This will lead to warmer mid-latitude winters and colder Arctic winters.  This has not occurred in recently years, as both have warmed.

Consequently, a summer BOE is highly unlikely to result in a year-round BOE, as the large heat loss that would occur during an Arctic winter, would cause the temperature to fall significantly below freezing.  However, a year-long BOE might be preferable to a seasonal BOE, as it would allow substantial heat to be lost, slowing the global temperature rise.

If the Arctic is no longer an ice desert in winter, but a maritime environment, then there may be much more cloud formation which acts as a "blanket" reflecting back outgoing radiation before it escapes to space. This is how a BOE could possibly sustain over the dark winter months. The most recent research has shown that the autumn season is becoming more cloudy as the ice retreats.

https://www.atmos-chem-phys.net/16/14343/2016/acp-16-14343-2016.pdf

[Bruce Steele]

  Burnrate, Freshwater hosing and the bipolar seesaw are much better covered by AbruptSLR but the "Great Salinity Anomaly" was an example of a MOC slowdown caused by Beaufort Gyre circulation changes.     [5] Significant changes in the freshwater flux from the Arctic Ocean were documented by Dickson et al. [1988]; most notable was the “Great Salinity Anomaly” (GSA). The GSA appeared in the Greenland Sea in 1968 and circulated around the subpolar ocean for at least 15 years. Various explanations for the GSA have been offered [Dickson et al., 1988; Walsh and Chapman, 1990; Mysak et al., 1990; Hakkinen, 1993, 1999]. Proshutinsky and Johnson [1997] gave evidence that such salinity anomalies may originate inside the Arctic Ocean because of a redistribution of freshwater. Belkin et al. [1998] revisited the GSA of the 1970s and documented the existence of two additional subpolar salinity anomalies in the 1980s and 1990s.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2008JC005104#jgrc11238-bib-0017

[Rich]

At some point the Beaufort Gyre will reverse and a very large amount of surface fresh water , similar to the amount of fresh water in the Great Lakes, will head to the Atlantic.
 

We've had a few low pressure systems which have reversed the gyre this year for a few days at a time. No sign of warm water surfacing from that.

I imagine it needs to reverse for quite a while to produce the impact you are describing.

[Bruce Steele]

Rich, " Great Salinity Anomaly " was back in 1968 . Much of what we are used to seeing on the satellite record and what we expect to see each year does not include a Gyre reversal. We don't have a satellite record of weather conditions that resulted in the Beaufort reversal that long ago. My reason for bringing this issue to the BOE discussion is we are making projections , or peering into the future without considering the ramifications of historical events in the relatively recent past.
 I get confused with cyclonic and anti-cyclonic systems and how they precipitate a reversal, I just know reversals do happen and they have large influences on decadal weather patterns after they spill fresh cold water into the North Atlantic.

[Lou]

Let me also express my thanks for this thread.

In my view, a near-term (as in under a decade) BOE with a frequent recurrence is a certainty.  The amount of GHG in the atmosphere already plus melting and other changes already set in motion guarantee it.  The most pertinent question then becomes: OK, what happens next?

While I am NOT a climate scientist and do not want to appear to be impersonating one online, it seems clear to me simply from a systems basis that a BOE is not just another milestone along the way, but an event that could trigger enough changes to constitute a true biosphere tipping point.  And given all the variables in play, I am not in the least confident that we know how that will play out in different time frames.

For example, will the first (or first few) BOEs make ensuing ones more or less likely?  And once we have the first one, how many will we see in the ensuing decade?  None?  Three?  Nine?  (I realize that that question is a probabilistic one, given the huge influence weather is likely to continue to have post first BOE.)  Will even a single BOE have any meaningful effect at all on public sentiment and therefore public policy?  Where I live (the US), I think the answer is, sadly, "no".

I've been following energy and climate issues very closely since early 2003, and I find all this uncertainty about the advent of BOEs terrifying.

[prokaryotes]

Do not focus so much on the ice extent as a switch to something new, Arctic sea ice decline is more like the most visible positive feedback from a warmer climate. Things already change drastically and less sea ice will make those changes more pronounced.

Think of the satellite observed sea ice loss since 1979 as a transition modulated by the amount of greenhouse gases. General understanding currently is that the jet stream (the polar vortex) becomes more meandered, resulting in more stuck weather patterns - due to slower moving Rossby waves, since the polar vortex jets expand farther south.

Interactions also to consider, rate of iceberg and freshwater discharge from Greenland and river runoff in the Arctic circle, Ocean currents, waves and coastal erosion, salinity/halocline in the Arctic Ocean, NAO (see for instance this https://twitter.com/climate_ice/status/1150478225241305088).

General trend is temperature gradient in the northern hemisphere weakens, with the exception in the Greenland regions (see for instance Cold Blob anomaly), OR where cold Arctic air dives farther south, meets much warmer air, storminess increases (Hansen: Frontal (cyclonic) storms with hurricane-like winds, which, with rising seas and storm surges, will devastate thousands of coastal cities)  The planet is on a path to a warmer state, losing polar ice.

Implications are far reaching, negative for crop cultivation, biodiversity, ecosystems, atmospheric chemistry, profound on every level, and likely will last roughly 200,000 to 1,000,000 years - based on past such events in geological times.

However, our civilization can modulate the extent of change still, and maybe we develop more sophisticated negative carbon technologies - but at this time things like carbon capture and storage are not economically viable, remain largely untested, containments may leak over time.

[Tom_Mazanec]

Can computer models help? For example, a recent simulation of the Earth's magnetic field underwent a reversal, even though it was not "hardwired" in.

[rboyd]

I find the most frightening aspect of this topic to be the interaction between societal inertia and the possibility of a bifurcated change in a large earth system - the Arctic and the general climate.

The state change between an ice desert and a maritime environment will be extremely large, while the rate of that change may be very rapid. As we have seen, the Arctic can lose large amounts of ice volume while losing a much smaller amount of ice area/extent; the latter being a greater determinant of albedo levels, ocean stratification, and increased air humidity levels. At some point, perhaps very close, the ice volume reaches a critical level where area/extent losses will accelerate very rapidly - leading to a rapid transition to ice free in September.

Then we have the accelerating effects of reduced albedo as ice area/extent loss becomes greater and greater in August, then July, then June (the summer solstice). Greatly increased cloudiness during the winter months (due to prior months maritime environment), together with water turbulence and halocline mixing, may then serve to significantly reduce winter ice regrowth and therefore limit the amount of ice at the beginning of the summer season.

I am not a climate scientist, and the above is speculation, but I do consider that there exists a probability for a "cliff" like rapid transition which could easily outpace human society's ability to comprehend, let alone instigate, the scale and pace of change that would have any chance of reversing/controlling this process before it becomes self-fulfilling and irreversible in human timeframes.

Hopefully there are some significant negative feedbacks that will put a brake on such a cliff dive. As has been noted above, the Arctic has experienced conditions more akin to Florida in the past so there is no reason why it should stay as an ice desert - even in the dark of winter.

From a technological point of view the ability to stop clouds forming on a massive scale in winter (to allow radiation to escape to space, though water vapour itself is a potent greenhouse gas), and to enhance surface reflectivity and cloudiness in summer on the same massive scale (to stop radiation being absorbed at the surface) would be required. It seems that humanity is spending more on sending Tesla roadsters to space than on such technologies.

[philopek]

........I am not a climate scientist, and the above is speculation..........

I'd say an educated guess, neighboring a solid forecast, much more than a speculation IMO

In one "word" +1

[dnem]

I tend to agree, but the key question is how many years elapse between the first BOE right at the minimum and millions of extra kilometers of ocean being regularly ice free for several months of insolation and mixing.

[philopek]

I tend to agree, but the key question is how many years elapse between the first BOE right at the minimum and millions of extra kilometers of ocean being regularly ice free for several months of insolation and mixing.

I think "several months" is still far away but then a smaller, later and thinner ice coverage in winter will have a significant impact on mid-latitudes and the neighboring "Tundra"

To name all things in play would become TLTR here but consider methane, methanhydrates, ocean currents, SLR ( the only thing IMO that will really hurt long term and world-wide while many other factors can be worked around through short -mid and -long-term migration.)

The list can continue almost endlessly but certainly there will be regions that profit and others that suffer and again others that become non-habitable.

The first things to happen, more or less immediately will be climate shifts, heatwaves, heavier and more frequent storms and droughts which BTW is already in the process and clearly visible, only that there are always a few "back to normal" years in between that spoil the view for most and are welcome to further pull their scams for others.

[Klondike Kat]

I think "several months" is still far away but then a smaller, later and thinner ice coverage in winter will have a significant impact on mid-latitudes and the neighboring "Tundra"

To name all things in play would become TLTR here but consider methane, methanhydrates, ocean currents, SLR ( the only thing IMO that will really hurt long term and world-wide while many other factors can be worked around through short -mid and -long-term migration.)

The list can continue almost endlessly but certainly there will be regions that profit and others that suffer and again others that become non-habitable.

The first things to happen, more or less immediately will be climate shifts, heatwaves, heavier and more frequent storms and droughts which BTW is already in the process and clearly visible, only that there are always a few "back to normal" years in between that spoil the view for most and are welcome to further pull their scams for others.

You do realize that SLR is unaffected by melting sea ice, don’t you?  Heavier storms are caused by the contrasting temperatures.  Droughts have decreased during the recent rise in temperatures.

[philopek]

I think "several months" is still far away but then a smaller, later and thinner ice coverage in winter will have a significant impact on mid-latitudes and the neighboring "Tundra"

To name all things in play would become TLTR here but consider methane, methanhydrates, ocean currents, SLR ( the only thing IMO that will really hurt long term and world-wide while many other factors can be worked around through short -mid and -long-term migration.)

The list can continue almost endlessly but certainly there will be regions that profit and others that suffer and again others that become non-habitable.

The first things to happen, more or less immediately will be climate shifts, heatwaves, heavier and more frequent storms and droughts which BTW is already in the process and clearly visible, only that there are always a few "back to normal" years in between that spoil the view for most and are welcome to further pull their scams for others.

You do realize that SLR is unaffected by melting sea ice, don’t you?  Heavier storms are caused by the contrasting temperatures.  Droughts have decreased during the recent rise in temperatures.

Yes i'm aware that sea-ice does not add to SLR but the topic are the Climate Effects of BOE and the climate effects will accelerate Greenland melt, global warming in general and therewith Antarctic melt, it will accelerate Glaciers in the higher mountains to melt, i.e. South American Andes as well as in the Alps and the Himalayas.

And that WILL accelerate SLR.

There was i reason why i mentioned explicitly that the list is much longer and would be TLTR.
The reason was that i wanted to avoid that one after another comes up with one of the parts i left out because the time and the space are limited.

I hope i was able to clarify why i mentioned SLR, because accelerated SLR will be one of the indirect consequences of regular and extended (in time) BOEs in the Arctic. Some would probably tend to say it's a direct consequence, that depends of the definition of direct.

[petm]

Don't know if you've noticed, but the state of the ice has a huge effect on the weather, even locally. BOE is likely to have extreme effects.

Or maybe not; maybe it will be a negative feedback. Fingers crossed but not holding my breath.

Want to take that risk?

(PS. In my opinion, specific arguments and projections are counter-productive. Very few if any have an inkling of what's coming. It's better to just say, it'll be big and it'll be bad.)

[Klondike Kat]

Don't know if you've noticed, but the state of the ice has a huge effect on the weather, even locally. BOE is likely to have extreme effects.

Or maybe not; maybe it will be a negative feedback. Fingers crossed but not holding my breath.

Want to take that risk?

(PS. In my opinion, specific arguments and projections are counter-productive. Very few if any have an inkling of what's coming. It's better to just say, it'll be big and it'll be bad.)

I agree that specifics and arguments are counter-productive, but then you make a projection that it will be big and bad.  How do you know, if we do not have an inkling of what is coming?

[Archimid]

 I think there are two potential types of BOE.

 One BOE is like 2012, the last of the ice is destroyed by mechanical energy and Arctic geometry. In this case there will be an energy deficit come the freezing season, rapid refreeze happens, NH cooling happens. The following year will be a record year for ice formation much like 2013 was a record gain year. I suggest we call that a cold BOE

The other is like 2016, excess high temperatures coupled with less ice to melt caused the Arctic to remain warm well into winter and produced a record low maximum. While CO2 alone is not enough to cause this event, there is plenty of heat in the surrounding hemisphere and ocean to  melt what remains. A well timed super El niño or stuck weather pattern can do it. I suggest we call this a warm warm BOE.


If a cold BOE happens early ( July/August) it may become a warm BOE.

If albedo feedback effect or other feedbacks do not happen (as consensus science thinks), then the CO2 induced BOE will likely be a warm BOE as it can only happen when enough heat is accumulated due to CO2. 2050 is a good date for such an imaginary event.


A cold BOE will have record ice growth. A cold BOE, like a warm BOE, will be coupled with massive amounts of snow, but the snow may start earlier, helping raise continental albedo, helping the freezing season.

If enough snow falls, then the mountains of snow may keep albedo high well into spring and summer further helping the freezing season and the start of the melting season.

The ice will have all the help it needs to grow. The problem is that the following melting season all the ice is first year ice. Will another BOE happen afterwards, this time a warm BOE? very likely.

A Warm BOE will delay the freezing season and snow of the NH. The earlier it happens the more warmth have to be dissipated before freezing commences and the more humidity will escape the open Arctic ocean. Snow will be late, but vast. Freezing slow and remaining ice thin and mobile. A an earlier even warmer BOE follows.

[TerryM]

Archimid


Do your scenarios allow for tropical heat to be drawn into an expanding arctic vortex?
I see a larger cool area evolving vs the small cold region we're familiar with. The expanded cool vortex slowly becomes an expanding warming region possibly centered over Greenland's ice cap.


The heavy arctic mists that Jennifer Francis wrote of will eventually insulate the arctic through the dark winter months when insolation isn't available. That's when the year round BO occurs. That's when this era truly ends.


No idea when this occurs, but eventually it will.
Alligators on Baffin Island? - it's happened before.


Warm BOE, Cold BOE - eventually permanent BO.
Terry

[kassy]

The last couple of years look like we are working on a warm one.
If you look at the arctic bathymetry that works well with that.

See Uniquorns great gif in post #4300
https://forum.arctic-sea-ice.net/index.php/topic,2591.msg215000.html#new

If it comes early in the year the mixing with deep waters will also be a bigger problem.

BTW i think it is a continuum. Type 1 or cold is the death of old thick ice. But notice 2012 did not came near a BOE. After that we have seen refreeze trouble around the edges and an ever thinner ice pack. So i think we are working on ´warm BOE´regardless. (And then when the pattern is setting up for that it opens up for type 1 but that probably leads to the other anyway).

[Archimid]

Do your scenarios allow for tropical heat to be drawn into an expanding arctic vortex?

I find it likely. I think the next super el niño is the end of the ice. Hopefully, we have a decade before that happens. 

[Tom_Mazanec]

Were there any meteorological effects of the record 2012 minimum, that might give a clue what the BOE might cause?

[oren]

I think hurricane/superstorm Sandy was named as one possible consequence.

[Tom_Mazanec]

Shrinking ice cap accelerating AGW?
https://www.kpbs.org/news/2019/jul/29/melting-ice-may-speed-climate-change/

[Tom_Mazanec]

Abstract
Observations show that reduced regional sea-ice cover is coincident with cold mid-latitude winters on interannual timescales. However, it remains unclear whether these observed links are causal, and model experiments suggest that they might not be. Here we apply two independent approaches to infer causality from observations and climate models and to reconcile these sources of data. Models capture the observed correlations between reduced sea ice and cold mid-latitude winters, but only when reduced sea ice coincides with anomalous heat transfer from the atmosphere to the ocean, implying that the atmosphere is driving the loss. Causal inference from the physics-based approach is corroborated by a lead–lag analysis, showing that circulation-driven temperature anomalies precede, but do not follow, reduced sea ice. Furthermore, no mid-latitude cooling is found in modelling experiments with imposed future sea-ice loss. Our results show robust support for anomalous atmospheric circulation simultaneously driving cold mid-latitude winters and mild Arctic conditions, and reduced sea ice having a minimal influence on severe mid-latitude winters.

https://www.nature.com/articles/s41558-019-0551-4