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Messages - FishOutofWater

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I wrote about what's happening over at a fading political blog the other day. Intense end warmings in the stratosphere have consequences. The sudden warming of the region from 60N to the pole from the surface to the top of the stratosphere is what I was referring to by the description "atmospheric convulsion." There's likely to be a horrific tornado outbreak on Monday and Tuesday as the storm that's now giving California a very late soaking reforms on the east side of the rocky mountains.

Zach Labe understands the physics of this situation better than I do - he's studying it for an advanced degree. I doubt he's reading this but I wouldn't mind being corrected if I made a mistake.

She blogged about that story here:
It's much quicker to read it than watch a freaking video.

She's clearly very smart with a PhD in particle physics. She's clearly an expert at physical modelling. What she appears to lack is training in the earth or ocean sciences. Brilliant physicists who are modelling experts may not have the same appreciation for how the earth works as someone who has done a large amount of field study. At least, that's my personal experience.

Arctic sea ice / Re: 2019 sea ice area and extent data
« on: May 16, 2019, 06:39:22 AM »
FYI the ECMWF & GFS agree on high pressure over the Arctic over the next ten days. They differ on details but it not a "good for shit" forecast. It's a result of large scale subsidence and spin coupling of warm air domes in the troposphere and stratosphere. We're seeing "big picture" phenomena.

Arctic sea ice / Re: The 2019 melting season
« on: May 15, 2019, 08:53:10 PM »
The light fog or thin low cloud situation is something that's in addition to the dewpoint being high. There is always water vapor, but in the Arctic water vapor pressure is often extremely low. Perhaps that's like a greenhouse with a translucent white plastic cover which acts as a light diffuser.

Arctic sea ice / Re: 2019 sea ice area and extent data
« on: May 15, 2019, 07:43:32 PM »
High pressure and clockwise rotation of the ice pack induce Eckman upwelling in the near shore waters of Alaska and Canada. The Coriolis effect deflects the ice towards the center of the high and it is replaced by water from below. If high pressure persists it slowly pumps up warm water from the Atlantic layer along the continental shelf.

At the moment little reason to suppose sea ice loss will accelerate, which makes the general disintegration of the sea ice all along the Arctic ocean edge from the Beaufort to the Greenland Sea all a bit of a mystery to me.

Persistent high pressure in May June and July is not good for Arctic sea ice, especially in the Beaufort sea.

Arctic sea ice / Re: The 2019 melting season
« on: May 15, 2019, 07:36:08 PM »
These high pressure subsidence zones over the Arctic ocean put warm air over the ice and open water resulting in an thin inversion layer above the ocean. This time of year it gets constant light so thick fog or clouds don't form but it's humid. This situation maximizes uptake of solar heat and keeps outgoing longwave radiation low because the heat goes into melting ice and warming ice water. An extraordinary heat trap is developing over the arctic ocean as we speak. And water vapor - dew points near the air temperature - plays a role in reducing outgoing longwave radiation because it's a powerful greenhouse gas.

Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: May 15, 2019, 12:26:25 AM »
A lot of less than spectacular stuff in this thread...

Global hurricane activity and energy release is tied to Pacific El Niño cycles because the western Pacific has the largest area of warm tropical and subtropical water on earth. Strong Asian monsoons cause wind shear that dampens westpac hurricane activity in the summer months. Thus is is true that global measures of hurricane energy release such as ACE do not show significant increases.

However, Atlantic hurricane energy release went way up after the 1997 El Niño. It correlates with increasing heat content in the tropical and subtropical north Atlantic basin. Some folks have theorized that the Atlantic has now gone into a cool phase of a so called cycle, but the apparent cycle was caused by aerosol cooling of the north Atlantic in the 60s and 70s. The apparent cycle is probably an artifact of that cooling episode.

As to the "slow down" in melting over the past 30 days, it happened because of the early melt out of the Pacific seas. The recent heat has melted Baffin island snow and the Labrador sea is about to go, but the central Arctic basin takes time to show the effects of unseasonable warmth.

Klondike wrote (in green):
However, after a fast start to the melt season, the ice loss has slowed dramatically this year.  The 30-day melt is one of the lowest in the satellite data (only six years have shown less).
The weather developing right now is exceedingly unfavorable for sea ice and melting is going to speed up. However, I think there's too much volume to melt to get a blue ocean event this year. We could luck out again as we did in 2016 with a period of cool stormy weather in July. However, I think we will see a new record minimum because of what's going to happen over the next 2 weeks. Time will tell.

Arctic sea ice / Re: The 2019 melting season
« on: May 14, 2019, 12:15:11 AM »
Yes, Frivolous, this is what I was concerned about 2 weeks ago when the end stratospheric warming went crazy. It set up a pattern of spin down from the stratosphere intensifying blocking patterns in the high north. The strong Scandinavian blocking led to very intense upward wave energy transfer that caused the powerful end warming in the stratosphere. Over the next several months the stratospheric spin down will repeatedly couple with blocks in the troposphere which also rotate clockwise. Upward energy transfer into the stratosphere is over for the summer but downward effects are possible when there's high pressure over the Arctic because the clockwise spins may align. You wrote:

For those who are not aware:

Meteorology speaking this setup is essentially the Holy Grail of having a record-setting Arctic sea ice loss during the summer.

Solar energy right now is booming over the arctic.  The best way to set up things for huge loses of sea ice is sprawling upper level atmospheric ridges of high pressure that exist from top down.

This is the path to dry sinking air and wall to wall sunny skies.

We have never had a May 20-30th GARGANTUAN RIDGE that preconditioned the ice for huge June and July loses.

Stay tuned

Over the weekend I reviewed the stratospheric patterns for summers for the past 20 years and found that the stratospheric end warming conditions increase the odds of the Arctic oscillation being positive or negative - in this case high pressure means negative - but there are many other things going on.

What's starting to happen in May looks like the worst case set up for Arctic ice melt. The figures I looked at showed variability that give me very low confidence in a July forecast based on the end warming patterns by themselves. However, we can use the end stratospheric warming information to evaluate the likelihood that a global model such as the CFS model is making a decent forecast. The CFS model struggles with ocean upwelling, melting snow and ice, and the evolution over time of SSTs, but, based on my experience it may have a good handle on large scale stratospheric tropospheric coupling in the summer.

If it does, were going to witness a new record low in sea ice extent, area and volume this year. The latest CFS runs predict the high pressure and subsidence over the pole and Greenland will persist into July. This CFS model forecast makes sense because of the intense late end season stratospheric warming at the end of April.

Arctic sea ice / Re: The 2019 melting season
« on: May 13, 2019, 11:15:13 PM »
The whole icepack is starting to rotate and it will get going when the forecast high pressure intensifies. However, it never moves that fast and the Siberian islands do cause ice to pile up and distort the pattern of rotation. The recent pull offs of the pack from both the CAA and Greenland are the first steps in the process. Next comes the powerful high pressure and we'll watch it slowly spin clockwise.

Arctic sea ice / Re: The 2019 melting season
« on: May 05, 2019, 05:18:54 PM »
We had very cold weather in the north central U.S. after Jan 15 this year as I forecast. Long range forecasts are notoriously hard to get better than climatology. The one I made before Christmas and posted elsewhere was about as good as those kinds of forecasts get. You got no "beast from the east" in Europe following the late December SSW but the north central and north eastern U.S. was brutalized by polar air.

Here's what happened in late spring early summer 1997, perhaps an analogous year to this one.

Arctic sea ice / Re: The 2019 melting season
« on: May 05, 2019, 12:10:48 AM »
What apparently is happening is that greenhouse gases are speeding up the Brewer Dobson circulation - the flow of air from the troposphere to the stratosphere and back. In this case is is causing subsidence over Greenland, the Beaufort sea and the high Arctic. This is why, barring the lucky occurrence of cool cloudy stormy July, I think we are likely to see a new record sea ice minimum this September.

As Cohen wrote in his blog post, this subsidence tends to persist. A very warm sunny May maximizes the input of solar heat early, potentially allowing for a high amount of feedback due to reduced albedo in response to low early snow and sea ice extents.

These stratospheric processes may have a large impact on September sea ice extent, area and volume. Depending on the index, Greenland has had the 2nd earliest or earliest early melting and the western side of Greenland had little snow in the winter so it will rapidly darken when the west side has surface melting.

The stratospheric events of the past 6 months have been a real shocker. I think the high pressure over Greenland and the western Arctic will likely continue into June.

Below is an image of the lower stratospheric temperature and circulation at 17Z 4May19. It shows warm air sinking over the pole. That subsidence continues into the troposphere.

Arctic sea ice / Re: The 2019 melting season
« on: April 30, 2019, 02:17:25 PM »
This image does not show warm arctic cold continents. Excellent image, Sark.

It shows something far more important. It shows the impingement of warm Atlantic and Pacific water into the Arctic and the increasing amounts of ocean heat that are entering the Arctic atmosphere from the Arctic ocean itself as the ice thins. The cold weather persists where thick ice piles up north of the CAA and northern Canada is still cold. Even Siberia is being warmed by the Atlantification of the Siberian side of the Arctic.

Graphics for the 500mb heights and ice thickness would be best done for exactly the same time periods to visualize the relationships between retreating and thinning ice, surface temperatures, and changes in atmospheric circulation patterns. In the post above, the comparisons are apples vs oranges.

It's very clear to me that there has been a large increase in heat transfer from the Arctic ocean water to the atmosphere. We will reach a planetary tipping point when there's so little ice that winter cloudiness cuts total radiative heat loss from the Arctic. Then we can expect really weird things, perhaps like super polar lows in midwinter along the shores of Siberia.

Arctic sea ice / Re: The 2019 melting season
« on: April 23, 2019, 03:10:28 AM »
Blocking highs are not something new, but their intensity and persistence in increasing. The record Greenland melt years of 2010 and 2012 were associated with strong high pressure over Greenland. Those were also bad years for the Arctic sea ice.

The coming together over the Arctic ocean of the Alaskan block and the Greenland block is particularly bad for sea ice because it creates a dipole that imports heat from the Pacific and exports ice through the Fram Strait.

Arctic sea ice / Re: The 2019 melting season
« on: April 22, 2019, 05:03:35 PM »
Blocking highs are features that the models have trouble forecasting and that's just what we're seeing now in the 120 to 240 hour forecasts. There's a major disagreement between the GFS and the ECMWF on the surface and 500mb pressure and height patterns in the Arctic. The European model is the best model, but all the models have problems with blocks.

However, I think it is helpful and useful to look at what the models are forecasting because it's information about the state of the oceans and atmosphere at any given time. I think the ECMWF forecast of developing high pressure in the Arctic is probably correct.

Apparently, it was chugging along in the first half of 2018 then dropped precipitously in the second half.

Arctic sea ice / Re: The 2019 melting season
« on: April 20, 2019, 07:05:11 PM »
Thin clouds close to the surface of sea or land ice that are caused by ice chilling of warmer air above have the potential to transmit huge amounts of heat to the ice. Because of the inversion, there is little mixing  with the air above so surface solar heating doesn't go back into the air above the inversion. Obviously, thick clouds may be very reflective and protective to the ice below. Understanding cloud types and how they are changing as the Arctic warms and ice melts will be a key to predicting Arctic change. The recent discovery of these thin near surface clouds that increase warming rates is one explanation for the failure of older models to predict the rapidity of Arctic warming.

Arctic sea ice / Re: Holy Sh!t: Year-Round Arctic BOE Imminent
« on: April 20, 2019, 02:30:55 PM »
That counterpunch article is sloppy from a scientific perspective. The vast continental area of Eurasia will still get cold in the winter when there's less (or no) sea ice in the Arctic ocean in the winter. Snow will still fall over Siberia and the jet stream will still be intense on the margin of the western Pacific with Eurasia.

We have climate models that can be used to analyze these scenarios. There are papers reporting the results of such studies. If you're going to write articles about the BOE event you should read about those studies before you write your story. It doesn't look like this author did that.

Arctic sea ice / Re: The 2019 melting season
« on: April 17, 2019, 05:59:39 PM »
There has been a major shift in the atmospheric circulation pattern around the Arctic. The ridging which persisted over Alaska in February and March has ended while a strong ridge has set up over Scandinavia. This has allowed for an apparent recovery on the Alaskan side of the Arctic, although the reformed ice is very thin and won't last long. The heat on the Atlantic side won't show large effects on metrics because it is going over thick ice that was piled up at the exit to the Fram strait.

One not so good thing for sea ice about this atmospheric circulation pattern is that the coldest anomaly is focused on Baffin bay with strong north winds down the bay. This will enhance the circulation of warm salty water into the bay along the coast of Greenland and the flow of icy fresh water out of the bay into the Labrador sea. This will favor continued overturning in the Labrador sea and the release of oceanic heat to atmosphere over the far north Atlantic and subpolar seas.

Arctic background / Re: Barneo 2019
« on: April 17, 2019, 04:14:08 AM »
Videos of the ice this year looked bad when they first landed. I'm not surprised they called it off. I wonder if the political haggling was an excuse to fog the reality that the ice wasn't suitable for occupation this year.

Arctic sea ice / Re: Latest PIOMAS update (April 2019)
« on: April 16, 2019, 06:12:57 PM »
None of those curves have any predictive power, in my opinion. Weather and changes in the influx and outflow of water masses will determine what happens to area, extent and volume over the coming years. Weather is always factor number 1.

Will there be a mid month volume update? I'm very interested to see how early the drop in volume begins this year.

Arctic sea ice / Re: The 2019 melting season
« on: April 14, 2019, 04:09:38 PM »
Yes, Wallen, there has been a trend over the past 5 years or so to less shelf ice on the east coast of Greenland. This is having profound impacts. Mid to deep water formation has increased in the Greenland sea because salty water has cooled on the shelf then descended to deep water. This warm salty water is also melting glaciers from below, increasing their flow and melt rates.

There are papers on this and I'm sure someone here knows the links to some of them. I don't have the links at my command.

The NSIDC reports that the past 2 years have had very heavy snow on SE Greenland and that accumulation exceeded melting. This is associated with the tendency to a Greenland vortex that we've had for 2 years. In the big melt years of 2010 and 2012 high pressure (and a dome of warm air) dominated and warmed Greenland.

As noted in the previous post, exceptional winter snow accumulation and heavy, summer snowfall, drove the net snow input mass to 130 billion tons above the 1981 to 2010 average. This was followed by a near-average melt and runoff period, resulting in a large net mass gain for the ice sheet in 2018 of 150 billion tons. This is the largest net gain from snowfall since 1996, and the highest snowfall since 1972. However, several major glaciers now flow significantly faster than in these earlier years. The net change in mass of the ice sheet overall, including this higher discharge of ice directly into the ocean, is not clear at this point but may be a smaller loss or even a small gain. This is similar to our assessment for 2017, and in sharp contrast to the conditions for the preceding decade.

This is relevant to this melting season because the incoming Atlantic water is saltier and warmer without Greenland melt water mixing in. Moreover, the Gulf Stream and Norwegian currents are strengthened by intensified overturning circulation and the stronger sea surface height gradients this pattern produces. The rate of sea ice and fresh water export in the Labrador sea has also increased with increasing flow out of the Nares and CAA.

We'll see what this summer's weather brings us, but this is setting up to be a bad melt year and the early break up of east Greenland fast ice is but one sign of it.

Arctic sea ice / Re: The 2019 melting season
« on: April 12, 2019, 03:35:07 PM »
The amount of heat advected from the north Atlantic to the Atlantic side of the Arctic is going to be much greater than normal over the next 5 days. This atmospheric circulation pattern also increases the rate of flow of the Norwegian current into the Barents sea. storminess over the Atlantic side of the Arctic in mid April is not good for the sea ice because April would be cold and clear if there were high pressure and that would favor volume growth. This pattern favors volume loss over the ice pack margins and volume growth on north of Greenland on the exit doors to the Fram and Nares straits.

Arctic sea ice / Re: 2019 sea ice area and extent data
« on: April 12, 2019, 03:13:13 PM »
I would caution that the use of bulk averages for the arctic can be misleading. Average temperatures are reverting to the mean in both the GFS and ECMWF models but both models are doing it by establishing a powerful block over Scandinavia and deep cold low pressure over the Barents and Kara seas. This weather pattern will advect warm water into the Kara sea and will subsequently advect warm air over the Arctic from central Siberia. This pattern will increase the export of ice out of the Fram strait.

Of course, we shouldn't put much weight on forecasts over 5 days, but these blocking patterns have been going on for many months since early winter so we should be aware of the strong effects of blocking over Scandinavia and Alaska on sea ice.

Arctic sea ice / Re: 2019 sea ice area and extent data
« on: April 11, 2019, 04:45:45 PM »
A trend towards northerly winds in the Bering strait should stop the losses in the Beaufort, Chukchi and Bering seas for the next ten days or so. Some small increases are possible in the Bering sea.

The Atlantic side, however, will see continued blocking, forecast to intensify, over Scandinavia, which will intensify the flow of warm water and warm air from the Atlantic into the Barents and Kara seas over the next ten days. There will a see-saw, as there often is in the Arctic tipping towards ice loss on the Atlantic side and ice favorable conditions on the Pacific side over the next 10 days.

Arctic sea ice / Re: The 2019 melting season
« on: April 11, 2019, 04:28:56 PM »
There's going to be a blowtorch in the Barents in 5 to 6 days and temperatures will be well above normal over most of the sea ice covered areas in the NH. I don't see a sudden recovery coming. It does look like it will get cold in northern Siberia but that won't directly affect the ice.

Arctic sea ice / Re: 2019 sea ice area and extent data
« on: April 10, 2019, 02:04:56 PM »
There is going to continue to be anomalous heat in the Arctic in a week. The Atlantic side will be hard hit by warm air advection into the Arctic. There is a powerful blocking high over Scandinavia that is very persistent. It will advect large amounts of heat northwards from the Atlantic to the Arctic both in the atmosphere and by enhancing the flow of the Norwegian current.

Arctic sea ice / Re: 2019 sea ice area and extent data
« on: April 08, 2019, 05:04:21 PM »
The weather in the Okhotsk sea and Baffin Bay was exceptionally bad for sea ice. For weeks the ice in the Okhotsk was making the situation look better than it was because cold air outbreaks from Siberia persistently broke out over those waters in the winter and early spring. The spring warming there has caused the ice to melt rapidly, exposing the harsh reality on the Pacific side of the Arctic.

The drop in the Baffin bay was related to storms that brought strong warm easterly winds that drove ice away from the western shores of Greenland. This will have an impact in the coming weeks because these winds are strengthening the west Greenland current of warm salty Atlantic water into Baffin bay. In fact, the lack of an ice bridge in the Nares strait this winter has allowed a stronger than normal counter current of warm salty water to flow up the east side of the Nares strait at intermediate depths. Notice the salty water in the Nares at 100m in the map below.

Expect a warmer and saltier Baffin bay this summer than last summer and an earlier melt out.

Arctic sea ice / Re: The 2019 melting season
« on: April 08, 2019, 04:46:52 PM »
Northerly winds over the next 5 days will give the ice in the Laptev and Kara seas an opportunity for recovery, but then another powerful surge of warm air will flood in from the Atlantic. The GFS and ECMWF models disagree on the details of the low pressure areas, but agree on the big picture - the intense ridge that develops over Scandinavia and the powerful southerly flow that pushes into the Nordic seas.

Arctic sea ice / Re: Albedo-Warming Potential
« on: April 07, 2019, 08:00:31 PM »
Outstanding work, Nico. There is an added feedback that could kick in this year. All the heat is generally extracted from Pacific water before it passes into the Arctic from the Bering strait. With the exceptionally early clear out of Bering sea ice and the strong southerly winds across the strait this year, and the anomalously warm water already in the Aleutian region, we may see significant ocean heat advection from the Pacific to the Arctic this summer. That will cause a rapid wipe out of Chukchi and Beaufort sea ice if it happens and the melt out could progress into the central Arctic ocean.

Arctic sea ice / Re: The 2019 melting season
« on: April 06, 2019, 07:45:59 PM »
The unprecedented drop in sea ice extent, area and volume for late March and the first week of April is the result of unprecedented warm air advection from the Pacific and Atlantic ocean regions into the Arctic. It is as real as hitting your thumb with a hammer.

Maybe the weather will cool off and the melting will slow down, but reality is that Alaska just had the warmest March on record and the past 2 years have had record low amounts of ice in the Bering sea in March and early April. This is reality.

Arctic sea ice / Re: Latest PIOMAS update (April 2019)
« on: April 06, 2019, 07:13:57 PM »
The Atlantic side of the Arctic has SSTs that are above normal except for the center of the subpolar gyre which has been cooled by intense storms, strong polar outbreaks, and the outflow of greater than normal amounts of cold fresh water from the Arctic into the Greenland and Labrador seas. There has been a ring of warm salty water around the cold core of the gyre, indicative of active overturning in the Labrador sea. Mercator ocean profiles in the Labrador sea are consistent with greater than normal overturning this winter, but there was also an influx of very cold relatively fresh deep water into the 2000m to 3000m layer, perhaps deep overflow water from the Nordic seas.

That SST map displayed in the comment above is not consistent with DMI, Mercator Ocean and NOAA SST maps. These SST anomaly maps may compare to different 30 year baselines and may have different interpolation schemes. The Mercator anomaly map appears to be on the cool side but the cool water is in the subpolar gyre. An warm anomaly is located where Atlantic water enters the Arctic ocean on the east side the Fram strait. There is a warm anomaly on the west side of Novaya Zemlya This is not good news on the Atlantic side. There has been a powerful outflow of fresh Arctic water through the Nares strait and the CAA into the Labrador sea that has not interrupted the overturning circulation, but has left a cold anomaly in the core of the subpolar gyre. Warm salty water is now pushing up the west coast of Greenland into the ice free waters along the continental shelf margin.

Close comparison of Mercator's 100m map for 5April 2018 with 5April 2019 shows warmer water flowing through the Faroe Shetland channel this year. Increased heat flow through this channel leads to increased heat flow into the Norwegian current in the months that follow. Moreover, the strong storms that have recently entered the Arctic from the Atlantic have advected warm salty water at the 30 to 100 m level into the Barents sea.

What's going on now in the Arctic on the Atlantic side is not good news for the sea ice. We're going to need cool weather in the months ahead to keep this summer from being a very bad one for ice. This very early, apparently record early,  start to volume loss is very bad news.

Arctic sea ice / Re: The 2019 melting season
« on: April 02, 2019, 04:12:52 PM »
Uniquorn's animation of the Kara sea ice shows that Atlantic water is flowing into the Barents sea (and mixing with Siberian river water) then flowing into the Kara sea. The ice in the Kara sea looks very thin and is likely to melt out very early this year.

The distribution of thick ice is very unfortunate this early spring. The average thickness this year may be similar to what it has been for the past decade but the thick ice is piled up at the Arctic's exit doors. At the same time, warm and salty water is flowing in through the entrances. The Bering strait water has no heat content yet, but the break up of ice along the Alaskan shores of the Bering sea came several months early this year. It's possible that we could see the advection of heat in water flowing through the Bering strait this summer. This story of a man floating out to sea personalizes just how crazy this spring has been in Alaska.

So Rode and two other Nome men, 43-year-old John Culp Jr. and 33-year-old James Gibson, went out on the ice to move the equipment. They’d dug out a skiff out of snowdrifts and were going to use it to load some of the gear in to using leads, patches of open water between sheets of ice, to ferry it back to shore.

The open water alone was bizarre, said Rode: Usually the ice off Nome is solid until early May. People crab and dredge for gold through the ice.

“We never have open water this time of year,” he said. “Usually the ice is 8 feet thick. This year it was only a couple feet thick, not even frozen very hard. It’s bizarre.”

Arctic sea ice / Re: The 2019 melting season
« on: April 02, 2019, 12:25:33 AM »
Sea surface height maps are affected by differences in air pressure but there's consistent evidence that the volume of fresh water in the Beaufort high's fresh water dome has declined while salt water has flowed into the Siberian side of the Arctic, increasing the salinity of the Atlantic layer and the intrusion of salty water at 30m to 300m along the Siberian shelf edge.

We haven't merely been having warm weather in the Arctic. Winds have favored the influx of Atlantic and Pacific waters and the outflow of ice and fresh water through the Fram and Nares straits.

This is an extraordinarily bad start to the melting season. Maybe the weather will give the ice a break come June and July, but so far the models are predicting a stronger than normal peak melt season. Let's hope that they are wrong, but based on the present SST and atmospheric circulation patterns, the model forecasts appear to make good sense to me. Early warmth and albedo loss will tend to continue into the summer months because albedo loss is like a negative snowball for Arctic heat.

I agree that the IPCC has mishandled uncertainty and the carbon budgets are based on false confidence. The IPCC has ignored processes that have been identified but not well quantified. There may be processes not yet discovered. What we have learned between each iteration of the IPCC reports has tended to discover that the climate is more sensitive to GHGs than previously estimated.

A better handling of uncertainty would lead to less confidence in budgets and more urgency for action because the uncertainties skew towards higher impacts of GHGs on climate change.

Arctic sea ice / Re: 2019 sea ice area and extent data
« on: March 31, 2019, 06:13:52 PM »
I am not aware of a larger 2 day drop in March. The bottom dropped out and the sea of Okhotsk has a large area of thin dispersed ice that could blink out quickly in the next few days.

The weather is going to shift to deep lows in the Labrador sea over the next week. That's going to increase ice export and fresh water out of the Labrador sea and increase deep water formation where the cold air blasts off of eastern Canada onto the shelf edge. The coming weather will speed up ice loss in the Labrador and Greenland seas.

Arctic sea ice / Re: The 2019 melting season
« on: March 31, 2019, 04:57:34 PM »
In 2012 storms dispersed the ice in March, making the extent situation look much better than it was in reality. The thin dispersed ice rapidly melted in May and June. The situation this year is extremely bad because the thick ice is piled up on Greenland at the exit to the Fram strait and storms are thinning the ice at the margins at the Barents, Kara and Chukchi seas.

When we compare years it is most helpful to look at more than just the extent graphs and look at the thickness distribution and the salinity and heat at the 100m and 300m levels.

Yes, the weather this year will make the difference, but it looks very bad so far for sea ice. What we have seen in the past few weeks is the worst possible set up for a disastrous collapse this summer if the weather is warm and sunny.

And the CFS model predicts exactly that for the next 3 months, with a strong jet stream over the northern Pacific and a stronger than normal Aleutian low coupled with warm sunny high pressure over the western Arctic and Alaska.

This pattern ties in with the sudden stratospheric warming in late December coupled with the El Niño and active overturning in the Labrador sea.

All long range forecasts are subject to failure but this is forecast is about as bad as it gets for the sea ice.

Arctic sea ice / Re: The 2019 melting season
« on: March 18, 2019, 05:41:33 PM »
Both the Labrador current and the Gulf Stream are amped up this year. The lowest sea surface heights are in the Labrador sea, and SSH levels are higher pretty much everywhere else in the N Atlantic than they were just a few years back.

The images below tell part of the SSH story, but day to day comparisons of SSH may be affected by air pressure differences and differences in winds that may push SSH levels up along shorelines. However, it appears that the Beaufort gyre has lost fresh water volume and that deep convection is pretty strong in the Labrador sea this winter. That's consistent with intensification of the Gulf Stream and the Labrador current and with this winter's weather.

Arctic sea ice / Re: The 2018/2019 freezing season
« on: January 16, 2019, 06:52:03 PM »
FYI, the ECMWF and GFS models saw the SSW coming although they have been struggling with the details on how the deceleration of the vortex in the high stratosphere would work its way down in the atmosphere. I have been surprised about how well the CFS model has done at getting the big picture right about the SSW beginning to affect surface weather strongly around January 15.

I wrote about the developing SSW on 19Dec18.

The forum / Congrats to Zach Labe on his presentation award
« on: January 14, 2019, 10:16:09 PM »
Zach's dissertation research is going well and he's already getting recognition for his work. Congrats, Zach.

Happy to announce the AMS Middle Atmosphere 2019 Outstanding student presentation winners: Leong Wai Siu, Zachary Labe (@ZLabe), Jessica Oehrlein (@numberdance), Wanying Kang, Zane Martin, and Katia Lezine. @ametsoc #AMS2019.

Zach is doing research related to sudden stratospheric warmings - a complex and interesting topic. The SSW that started just before Christmas is working its way down from the stratosphere and is going to be bringing cold and snowy weather to the eastern U.S. and western Europe for at least the next 6 weeks and possibly through March.

There may be links between Arctic sea ice and SSWs but Zach would be the person who might be able to explain those links, not me.

Arctic sea ice / Re: The 2018/2019 freezing season
« on: November 01, 2018, 07:03:39 PM »
The NAO index has been positive this summer and fall. There's a reason it's called an oscillation. It doesn't mean there's an oncoming ice age every time it goes positive.

The rest / Re: The Trump Presidency (was "Presidential Poll")
« on: October 19, 2018, 04:06:13 PM »
You know, sometimes an old drunken prospector stumbles into gold, but it's far more likely that the old drunken prospector stumbles in a hole and falls flat on his face.

The thing is that Trump knows how to sell stuff and he knows how to make deals with crooks like Putin's oligarchs and members of the Saudi royal family. He has little to no experience or competence to do most of the things that democratically elected heads of state do. So he is unorthodox, but generally not in a productive way. He is far more likely to inadvertently start a war than to stumble to peace. Peace takes patience and preparation, not Trump's strong suits. War takes one ignorant mistake.

Arctic sea ice / Re: The 2018/2019 freezing season
« on: October 18, 2018, 03:53:09 AM »
Water that gets subducted into into subsurface layers takes years to do anything in the Arctic ocean.  When the oceanographers figure out when that water comes back up I will tell you or you will tell me. The paper did not report on subducted heat resurfacing. So the answer is, I don't know.

What's important to us now is that the Chukchi is changing rapidly before our eyes into a mostly ice free region in the arctic. This will affect both the atmosphere and the ocean in years to come and this year well into late fall and early winter.

I took another look at the Mercator scales. They were the same. Don't trust the forecasts.

Arctic sea ice / Re: The 2018/2019 freezing season
« on: October 17, 2018, 11:38:10 PM »
I think that some of the heated water discussed in that recent paper ends up in the Pacific water layer of the Beaufort gyre. It would be below the meltwater layer and above the Atlantic water layer.

Yes, those papers are related in more than just the authorship.

As to the darker color on the Mercator x-section, I tried to use the fixed scale that keeps the same color for the same temperature & salinity. It looks like that didn't happen with the image for the forecast.

I absolutely hate scales that change over time because I'm generally trying to see change over time.

Arctic sea ice / Re: The 2018/2019 freezing season
« on: October 15, 2018, 02:32:52 AM »
WACC is a pattern of relative warmth and cold in a warming climate. It doesn't mean that the continents are getting colder. WACC happens when the polar vortex is weak and cold air pours out over the continents in the cold months. WACC does not apply to summer.

The major stratospheric warming last February brought on a powerful WACC pattern. Snow hung on very late into spring in New England and really piled up in eastern Canada. Remember the "beast from the east" in Europe. hat was classic WACC related to the break down of the polar vortex.

And, yes, I have piles of firewood that I salvaged from downed trees in my neighborhood. Too many hurricanes. I'm thankful to all the scientists and technicians who go to the Arctic so that I can look at the data while sitting by a warm fire at home.

Arctic sea ice / Re: The 2018/2019 freezing season
« on: October 13, 2018, 03:39:02 AM »
I think that the effect warm air advection into the Arctic increasing clouds and downwelling radiation is a major uncertainty in modelling future Arctic conditions.

Received: 11 Jan 2017 – Revised: 27 Apr 2017 – Accepted: 28 Apr 2017 – Published: 01 Jun 2017

Abstract. Trends and variability of the Arctic sea ice extent depend on various physical processes, including those related to changes in radiative fluxes, which are associated with cloudiness and water vapour and, in turn, with the atmospheric moisture transport over the Arctic. Aim of this work was: (i) to extract seasonal spatial patterns of the co-variability between the sea ice concentration (SIC) and the surface downwelling longwave radiation (SDL) in the Arctic Ocean during the 1982–2009 period; and (ii) to estimate the correlation coefficients between these patterns and the indices associated to some climate oscillation modes (AO, NAO, PNA, PDO and AMO). Maximum Covariance Analysis (MCA) was the main technique used in this study. Among our results, we highlight two areas of maximum co-variability SIC/SDL centered over the Barents Sea in winter and over the Chukchi Sea in summer. In addition, some statistically significant correlations (at 95%) between the spatial patterns of co-variability and climate oscillation indices were assessed, e.g. with PDO and AMO in November–January, with NAO and AMO in May–July, and with PNA in August–October.

Several articles is have scanned indicate that downwelling radiation has the largest impact in the spring months. September sea ice extent isn't very sensitive to winter longwave radiation differences. Of course, that might change as winter warms and ice thins.
The Arctic region has warmed rapidly over the last decades, and this warming is projected to increase. The uncertainty in these projections, i.e. intermodel spread, is however very large and a clear understanding of the sources behind the spread is so far still lacking. Here we use 31 state-of-the-art global climate models to show that variability of May downwelling radiation (DLR) in the models' control climate, primarily located at the land surrounding the Arctic ocean, explains 2/3 of the intermodel spread in projected Arctic warming under the RPC85 scenario. This variability is related to the combined radiative effect of the cloud radiative forcing (CRF) and the albedo response due to snowfall, which varies strongly between the models in these regions. This mechanism dampens or enhances yearly variability of DLR in the control climate but also dampens or enhances the climate response of DLR, sea ice cover and near surface temperature.

At this point I think it's too soon to know if we are reaching a tipping point on the Alaskan side of the Arctic, but we have seen some stunning changes the past 3 years.

Arctic sea ice / Re: The 2018/2019 freezing season
« on: October 12, 2018, 02:32:50 PM »
The problem on the Bering side is the unprecedented heat flux into the Arctic. Warm, moderatly salty Pacific water has flowed into the Arctic then descended to the 30m to 100m level, below the fresh water layer caused by Siberian river influx.

There's a rapidly growing amount of heat in the Pacific water layer above the Atlantic water layer which is shoaling as freshwater is flowing out of the Arctic through the CAA and the Fram strait.

The present weather and ocean current patterns are increasing the heat content of the Arctic ocean. Sooner or later depending on late spring and summer weather patterns the increasing heat will lead to a record below 2012 and the heat will continue to retard sea ice recovery in the dark months.

Arctic sea ice / Re: 2018 sea ice area and extent data
« on: October 11, 2018, 08:28:27 PM »
More open water would lose more heat to the atmosphere during the dark months if clear skies allowed radiational cooling. So far, that has not been the case. Moreover, warm water has been pouring into the Arctic from the Pacific like we have never seen before while ice and fresh water are being pushed out through the Fram and the CAA at a higher than normal rate.

All in all, this looks like the Arctic is being "Atlantified" and "Pacified". This bodes ill for sea ice.

Arctic sea ice / Re: The 2018/2019 freezing season
« on: October 07, 2018, 03:48:56 PM »
Careful analysis of Mercator ocean cross sections and animations led me to conclude that warm salty water wrapped into the coastal area near the tip of Greenland, then was cooled by intense storms and cold air, last winter and early spring. Oceanic deep convection was intense after the major stratospheric warming drove cold air towards the Labrador sea and the far north Atlantic.

Summer and early fall cool SST anomalies south of Greenland are indicative of a shallow warm fresh layer that has been disturbed by storms. And amplified flow of cool water from the CAA through the Labrador sea into the north Atlantic. Cold SST anomalies in the late winter and early spring are indicative of weak deep convection, not summer temperatures.

Apparently a major reason that warm Atlantic water was moving into the Arctic from 2005 through 2012 was a weak overturning circulation. Instead of heading for the Greenland and Labrador seas, warm salty water headed up the coast of Norway for the Arctic ocean.

There's a recent report that deep convection in the Greenland sea has increased as ice has decreased on the continental shelf edge. Salty water is now able to penetrate the shelf then cool and sink.

There are probably other reasons that the Atlantic side of the Arctic ocean is apparently cooler than it was a few years ago. One may be that it's actually warmer at depth in parts of the Barents sea region. Stormy weather directs more water to the right of the Fram strait towards Murmansk and the Barents sea. Stormy weather prevents warm surface layers from building up, but the subsurface is warmed by mixing.

There's a lot going on. I await reports from professional oceanographers to make sense of it all.

The rest / Re: The Trump Presidency (was "Presidential Poll")
« on: October 07, 2018, 04:57:00 AM »
If you don't support or enable Trump, that rant wasn't directed at you.

At this point in time every delay in dealing with GHGs means more people and living things will die. No one knows exactly what the climate sensitivity to GHGs is but we are already at Miocene CO2 levels and there are enormous reserves of permafrost that will release massive amounts of CO2 when warming reaches 1.5 Celsius above pre-industrial levels. And we all know that the albedo will drop when Arctic sea ice is gone in the summer. There are many amplifiers when warming passes 1.5 Celsius and because we are warming the climate very quickly the amplifiers will tend to go off one after another if we don't rapidly curtail GHG emissions.

This is life and death for millions of people. Delay and denial equal death. My rant above may seem rude and uncivil but it pales in comparison to what is happening right now in the U.S. Decisions are being made that will lead to untold amounts of suffering.

The rest / Re: The Trump Presidency (was "Presidential Poll")
« on: October 07, 2018, 02:14:22 AM »
Yes, Lurk, it was all a conspiracy led by Hillary to get at Kavanaugh and Trump.

You know, that teenage drunk might have bagged my groceries at Safeway. There was a co-op closer to me but that was the closest supermarket to where I lived in the '80s. Her story was believable to me, but it isn't what convinced me that Kavanaugh is totally unfit for the job. His whiny-assed, entitled, whack-job rant convinced me he has no business wearing robes unless it's at a toga party. He is incapable of being judicious.

My daughters were in elementary school at the time so I didn't have to worry about Kavanaugh. He liked them young, but not that young.

Fuck Trump, his enablers and all of his supporters. He has dragged the reputation of this nation into the dirt. He is setting the stage for an economic crash by pulling out the control rods like they did at Chernobyl. It's insane to be running huge deficits so that corporations flooded with cash can get tax cuts. The housing market is getting strangled by rising interest rates, emerging markets are getting whacked by the money draining out of their economy as the U.S. takes in more money to fund its deficits, and inflation is getting pumped up by tariffs.

The main reason this isn't like 1929 is that the rest of the world isn't following Trump's lead and there aren't reparations and costs from WWI. Trump is driving the U.S. economy to asset inflation and speculation just like the roaring 20s. Profits pumped up by tax cuts and deficit spending, however, are not sustainable because the economy depends on consumer demand. The U.S. economy is going to bust before Nov. 2020 and Trump will have made the recession worse.

And fuck Trump and his enablers for supporting polluters and getting in the way of environmental progress. This administration is dirty and corrupt. I will feel safer when Trump is locked up behind thick iron bars, but America and the world will continue to suffer from his corruption and stupidity long after his is gone.

I believe in freedom of speech so go ahead and enable Trump if that's your thing <snip; N.>

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