Arctic Sea Ice Extent, Area, and Volume

[FPizz]

1 hour ago, forkyfork said:

they have been chasing a recovery for over a decade

Its been more talk of ice free than recovery talk for the past decade.  

[forkyfork]

1 hour ago, FPizz said:

Its been more talk of ice free than recovery talk for the past decade.  

it's been posted over and over again that 2012 was extraordinary and while the overall trend is down there will be significant year to year variability with the thinner ice. we're in one of the best ice retention patterns in years and the metrics are still well below average 

[TimB]

On 7/17/2021 at 1:16 PM, Weatherdude88 said:

The weenie tears are going to be epic.

 

I know this is way late, but why in the world would there be any tears if, despite all the evidence for it, it turns out that scientists were wrong about one of the greatest threats to humanity? 

[Vice-Regent]

8 hours ago, forkyfork said:

they have been chasing a recovery for over a decade

I am not seeing anything remarkable there are much cloudiness to accurately gauge sea ice area and extent is unremarkably low and normal as of late.

The evidence is piling on for warming elsewhere cooling the Arctic during the summer by tightening the 500mb layer in the atmosphere. Eventually the system will reach hysteresis it's already happening.

[etudiant]

53 minutes ago, Vice-Regent said:

I am not seeing anything remarkable there are much cloudiness to accurately gauge sea ice area and extent is unremarkably low and normal as of late.

The evidence is piling on for warming elsewhere cooling the Arctic during the summer by tightening the 500mb layer in the atmosphere. Eventually the system will reach hysteresis it's already happening.

Would note that the Antarctic appears to be mostly cooling. See:  https://www.mdpi.com/2073-4433/12/2/217/htm

Punch line in the summary discussion: ' The temperature trend from ERA5 is consistent with that from observations, in which a cooling trend dominates East Antarctica and West Antarctica, while a warming trend exists in the Antarctic Peninsula except during austral summer.'

[Vice-Regent]

2 hours ago, etudiant said:

Would note that the Antarctic appears to be mostly cooling. See:  https://www.mdpi.com/2073-4433/12/2/217/htm

Punch line in the summary discussion: ' The temperature trend from ERA5 is consistent with that from observations, in which a cooling trend dominates East Antarctica and West Antarctica, while a warming trend exists in the Antarctic Peninsula except during austral summer.'

This trend won't persist if we keep increasing the GHG forcing. We will turn the global climate system into an equable state as existed during the late Miocene and prior.

There are reasons to be optimistic and none of those reasons involve geoengineering.

[Vice-Regent]

12 hours ago, Weatherdude88 said:

Northern Hemisphere NSIDC sea ice compaction still above the 1990's average.

 

With more high latitude compact ice surviving in the high arctic, parts of the Beaufort, and other seas, 2021 may be the start in a series of recovery years.

A negative AO would not only be helpful to snow weenies who live at mid latitudes in the northern hemisphere, but could add additional thickness to the already surviving compact sea ice pack. We want a negative AO for December, January, and February especially.

Yeah ... no. The upcoming winter will be crazy warm in the mid-latitudes. This +AO will persist.

[LibertyBell]

21 hours ago, forkyfork said:

 

Yes, it typically ends in mid September to around the Autumnal Equinox, as one would suspect it should since that's when daytime becomes shorter than nighttime.

 

[LibertyBell]

7 hours ago, Vice-Regent said:

Yeah ... no. The upcoming winter will be crazy warm in the mid-latitudes. This +AO will persist.

neutral after la nina right? Those are the warmest and least snowiest.

2001-02 was one of those

[etudiant]

12 hours ago, Vice-Regent said:

This trend won't persist if we keep increasing the GHG forcing. We will turn the global climate system into an equable state as existed during the late Miocene and prior.

There are reasons to be optimistic and none of those reasons involve geoengineering.

Surely true, but I'd really like some modeling explanation why there is a 40 year cooling trend in both East as well as West Antarctica.

It just seems a weird anomaly that needs to be understood.

[rclab]

22 hours ago, etudiant said:

Surely true, but I'd really like some modeling explanation why there is a 40 year cooling trend in both East as well as West Antarctica.

It just seems a weird anomaly that needs to be understood.

I’ve absolutely have no science skill regarding climate. Just thinking, though, could the fact that one pole is a landmass and the other an ocean have anything to do with it? As always ……

[LibertyBell]

On 7/29/2021 at 12:18 PM, etudiant said:

Surely true, but I'd really like some modeling explanation why there is a 40 year cooling trend in both East as well as West Antarctica.

It just seems a weird anomaly that needs to be understood.

check out the news on the anomalous freeze and snowfall in central and southern Brazil.  Old people saying it's the first time they've ever seen snow there and lots of crops destroyed in the freeze.

 

[ORH_wxman]

1 hour ago, Weatherdude88 said:

Slater Probabilistic Sea Ice extent showing 5.15 million square kilometers on September 18th. It's very possible NSIDC sea ice extent minimum will be greater than 5 million square kilometers, given current NSIDC area and compaction at high latitudes. Remember, we are ahead of 2013 in area for the date. 2013 had a minimum of 5.10 million square kilometers of extent.

Id be pretty surprised if we finished above 5 million sq km on NSIDC. 

Though this season has admittedly ground to halt. I would have never guessed if you asked 3 weeks ago that we would have higher area than 2013 right now. 

2013 goes through a pretty big stall the next week so we should fall below it at some point here. My guess is we end up in the mid/high 4s. 

[bluewave]

Even in a much warmer Arctic, record low pressures are still going to cause a slow down in the rate of loss. Extent losses have been below average for this time of year. So this has allowed the extent to pull back to the 2011-2020 mean for late July. Should we continue to track along this 2010s dashed line, it would mean a September daily minimum extent in the mid 4s range.

 

 

 

NSIDC September 10 year mean September daily minimum extents

2011-2020…..4.423 million sq km

2001-2010…..5.388 

1991-2000…..6.499

1979-1990…...6.959

[donsutherland1]

On 7/30/2021 at 8:49 PM, Weatherdude88 said:

Slater Probabilistic Sea Ice extent showing 5.15 million square kilometers on September 18th. It's very possible NSIDC sea ice extent minimum will be greater than 5 million square kilometers, given current NSIDC area and compaction at high latitudes. Remember, we are ahead of 2013 in area for the date. 2013 had a minimum of 5.10 million square kilometers of extent.

That model was blown out of the water so to speak last year with a forecast minimum extent near 4.48 million square km.

https://www.arcus.org/files/sio/31109/ucolorado_nsidc_slater_barrett.pdf

Last year's minimum extent was the second lowest on record at 3.555 million square kilometers (JAXA), or nearly 1 million square kilometers below the Slater Model forecast.

If 2021 has a melt season that matches the slowest of the 2000-20 period, Arctic sea ice extent would fall to 4.891 million square kilometers. A melt comparable to the slowest 2010-2020 melt season would bring it to 4.420 million square kilometers. The median 2010-2020 melt would bring it to 4.236 million square kilometers.

The ice is thin. At some point, it will almost seem as the bottom has fallen out when the thin ice melts away. I suspect we'll wind up with a minimum extent figure of 4.4 million square kilometers, but can't rule out a much larger drop in the end.

The implied probability of a minimum extent figure of 5 million or more square kilometers is currently about 11%. The probability of the 5.15 million square kilometer minimum on the Slater Model is just under 8%.

It will be interesting to see what happens.

 

 

[StormchaserChuck!]

Yeah, this +AO is lasting right into the Winter. 

[StormchaserChuck!]

Nice little rebound huh

[LibertyBell]

On 7/28/2021 at 9:11 PM, etudiant said:

Would note that the Antarctic appears to be mostly cooling. See:  https://www.mdpi.com/2073-4433/12/2/217/htm

Punch line in the summary discussion: ' The temperature trend from ERA5 is consistent with that from observations, in which a cooling trend dominates East Antarctica and West Antarctica, while a warming trend exists in the Antarctic Peninsula except during austral summer.'

this makes sense since the peninsula is surrounded by water.  That's the big difference between the Arctic and the rest of the Antarctic

 

[bluewave]

Very thin ice pack this summer if these record low MYI area figures are correct.

 

[Typhoon Tip]

Through both indirect and direct geo-physical various circuitry ...the following article probably is more connected/suitable for this thread. Example, "..Complex interplays between the AMOC and North Atlantic sea-ice cover in conjunction with salinity and circulation changes have been proposed as physical causes underlying the DO cycles..."

https://www.nature.com/articles/s41558-021-01097-4.epdf?sharing_token=qWMQcnRcVRZQmZ_yahYbd9RgN0jAjWel9jnR3ZoTv0ODQw4Na6S4LwvIIwjZ_S3NdBoG6pi8c5NBfIwoUKp1VK_OHHszXMnB3OMoyz8L8emOhG-hoDsJyn1YMubz_IampYbIRg_8P9vjnfIPPzRQwm6m9BfwEGfoLu0JsB4E2trSfyu4r947mOz1oZQlyxQxZLxaMkEINR4Wt7XEIrPrRkahci-lKgCSTZahFzlH7wM%3D&tracking_referrer=www.washingtonpost.com

"...Here, a robust and general early-warning indicator for forthcoming critical transitions is introduced..." c/o above -

I'd also point out that we in the field began involved in conjecture as well as reading formulated papers/science on the subect matter all the way back to the early 1990s.   Really interesting embedded statements, like:

"...Different lines of evidence from palaeoclimate proxy records indicate that Northern Hemisphere temperatures have varied abruptly at millennial time scales during previous glacial episodes, with corresponding changes of the AMOC between its weak and strong modes1,15,16...."

[donsutherland1]

On 7/28/2021 at 11:35 AM, forkyfork said:

they have been chasing a recovery for over a decade

FYI: https://arstechnica.com/science/2021/08/a-look-back-at-very-bad-predictions-of-global-cooling/

[donsutherland1]

8/5 Arctic sea ice extent: 5.902 million square kilometers (JAXA)

Smallest decline from 8/5-minimum (2000-20): 1.047 million square kilometers 

Smallest decline from 8/5-minimum (2010-20): 1.489 million square kilometers

Statistically and historically, there is virtually no chance that the minimum extent will be at or above 5 million square kilometers. 
 

Implied probabilities of a minimum extent of 4.5 million square kilometers or below: 

Unadjusted: 92%
Adjusted (conservative bias): 75%
 

 

[csnavywx]

24 minutes ago, Typhoon Tip said:

Through both indirect and direct geo-physical various circuitry ...the following article probably is more connected/suitable for this thread. Example, "..Complex interplays between the AMOC and North Atlantic sea-ice cover in conjunction with salinity and circulation changes have been proposed as physical causes underlying the DO cycles..."

https://www.nature.com/articles/s41558-021-01097-4.epdf?sharing_token=qWMQcnRcVRZQmZ_yahYbd9RgN0jAjWel9jnR3ZoTv0ODQw4Na6S4LwvIIwjZ_S3NdBoG6pi8c5NBfIwoUKp1VK_OHHszXMnB3OMoyz8L8emOhG-hoDsJyn1YMubz_IampYbIRg_8P9vjnfIPPzRQwm6m9BfwEGfoLu0JsB4E2trSfyu4r947mOz1oZQlyxQxZLxaMkEINR4Wt7XEIrPrRkahci-lKgCSTZahFzlH7wM%3D&tracking_referrer=www.washingtonpost.com

"...Here, a robust and general early-warning indicator for forthcoming critical transitions is introduced..." c/o above -

I'd also point out that we in the field began involved in conjecture as well as reading formulated papers/science on the subect matter all the way back to the early 1990s.   Really interesting embedded statements, like:

"...Different lines of evidence from palaeoclimate proxy records indicate that Northern Hemisphere temperatures have varied abruptly at millennial time scales during previous glacial episodes, with corresponding changes of the AMOC between its weak and strong modes1,15,16...."

Read through that paper once this morning. Will be combing it a few more times before I make up my mind on it. It obviously needs more confirmation and research, but if Rahmstorf et. al and now Boers are on to something with AMOC stability states, this is extremely bad news. AMOC instability falls into the category of low prob. but very high impact. Whelp, the probability might be higher than we appreciate.

Reminds me of a paper not too long ago, but it was more focused on the sub-polar gyre. Boer's paper is making the case that *most* CMIP models are too stable.

Link to that one: https://www.nature.com/articles/ncomms14375

[bdgwx]

If 8/6 ends up being the minimum that would be epic indeed.

[etudiant]

5 hours ago, bdgwx said:

If 8/6 ends up being the minimum that would be epic indeed.

Have to say that extent never seemed like a useful measure to me, but perhaps specialists could clarify that aspect.

Area is where it is at imho, while also recognizing that PIOMAS is really the ground truth.

[nycwinter]

8 hours ago, bdgwx said:

If 8/6 ends up being the minimum that would be epic indeed.

i remeber as a kid when you would come home from school and temps in september on one day were in the 50's in nyc due to a strong cold front...

[donsutherland1]

14 hours ago, Weatherdude88 said:

For 8.7.2021, JAXA sea ice extent shows an increase of 18,541 kilometers squared. Extent is now in 7th place for the date.

For the month of August this century, this is the earliest increase on record.

The weather is now transitioning to a pattern favorable for sea ice retention.

NSIDC sea ice extent shows a 81 k gain.

The finish of this melting season is going to be epic.

The minimum has not been reached. The trend is down even with some fluctuations.

[LibertyBell]

8 hours ago, donsutherland1 said:

The minimum has not been reached. The trend is down even with some fluctuations.

The new IPCC report is out- it's bleak.

https://twitter.com/i/events/1424568170749202438

The only way to stop these corporations is to execute them with the death penalty and to organize a Nuremburg style court system on them and seize their property and to utilize the military on them to destroy them to smithereens and round up their leaders and imprison them for the rest of their lives.  Money constitutes power and the only way to destroy power is to bring the force of arms against it.

[donsutherland1]

59 minutes ago, LibertyBell said:

The new IPCC report is out- it's bleak.

https://twitter.com/i/events/1424568170749202438

The only way to stop these corporations is to execute them with the death penalty and to organize a Nuremburg style court system on them and seize their property and to utilize the military on them to destroy them to smithereens and round up their leaders and imprison them for the rest of their lives.  Money constitutes power and the only way to destroy power is to bring the force of arms against it.

Yes. I saw this morning’s press conference. I am going through it. There’s also a great interactive feature.

P.S. Arctic sea ice extent resumed its decline.

[LibertyBell]

4 hours ago, donsutherland1 said:

Yes. I saw this morning’s press conference. I am going through it. There’s also a great interactive feature.

P.S. Arctic sea ice extent resumed its decline.

Don did you see the graphs of the different temp rises with different emission rates?  Would you say the most likely scenario is a 3C rise before stabilization occurs (if we achieve net zero by 2050.)  What kind of devastation would we see by a 3C temp rise?

By the way we need to cut down on both CO2 and Methane, otherwise all the efforts will be a huge failure.

They also mentioned a 2 meter sea level rise by 2100!