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Messages - FishOutofWater

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1
Arctic sea ice / Re: The 2019 melting season
« on: August 29, 2019, 05:42:38 PM »
That graphic of ice movement vectors overlaying the U. Hamburg ice map is most useful in showing that the stall in extent drop has not been caused by a stall in melting. Bottom melting has continued while the ice has been dispersed by the weather for the past week. The apparent stall isn't really good news for sea ice. The ice volume is still very low as we shall soon see in PIOMAS.

This melting season has been very interesting and complicated.

I think we are going to see one more period of extent drops. There is too much heat in the Arctic ocean for bottom melting to stop in the next week, so don't call the melting season over just yet.

2
Negative interest rates mean that there is money available right now to invest in solutions that will reduce or mitigate climate change, but not the incentives or the will to do so.

The problem is that we in the west are thinking like old people or we think we are exempt from the laws of nature because of our technology and wealth. The Bannon ideas are an obnoxious combination of both.

Russia is a very cold nation which will see some major benefits (longer growing seasons) from a warming climate as well as some major problems (fires and permafrost collapse). Because Russia's main source of foreign exchange is oil and gas, Putin is doing whatever it takes to keep drilling and exploiting oil and gas, climate be damned.

China is trying to adapt to climate change but will have major water problems because of it. China will benefit from developing green energy and they are working hard on improved green tech.

The U.S. is dysfunctional because old right wing assholes are running the show. We can do better. Climate destabilization is hurting U.S. farmers badly and stronger storms are savaging our coastlines. We are acting like old fools in the U.S.A.

3
Arctic sea ice / Re: The 2019 melting season
« on: August 27, 2019, 03:28:11 AM »
Heat is radiating out from the cloudtops and above so the polar atmosphere is becoming increasingly unstable as we move into September. The models are struggling to capture what's happening more than 3 or 4 days out.

There's still the potential to melt out dispersed ice on the Siberian side of the pole but the horse race is now for the second or third position. It's a good thing that 2012 is looking unbeatable. The fires in Siberia and the Amazon have been depressing enough. We don't need to see any new sea ice records this year to get the message across that the climate is in trouble.

4
Arctic sea ice / Re: The 2019 melting season
« on: August 19, 2019, 01:15:15 AM »
Sea surface heights respond to air pressure patterns. Sea surface heights and fresh water contents build up under the Beaufort high when in a year with strong high pressure and the heights lower and the fresh water drains under lower pressure. You might consider it like breathing in and out, but it's fresh water content. The low pressure years are generally cooler and are often viewed as recovery years. However, they make it possible for the warm high pressure years to build up melt water under the center of high and pull up warmer water from below on the continental shelf margins.

The process of warming and ice loss takes many summers and the apparent recovery years enable the years of large losses.

A similar situation happens with Greenland melting but there's also an annual cycle caused by thermal expansion/contraction and much higher pressure in the summer than in the winter. The intense winter Greenland sea low pressure pattern spins water out of the region. One melt season doesn't change the gravitational situation very much, but the Grace satellites are very sensitive.

Let me reemphasize, that weather is the key here although there are many other things going on.

Yes, the heavy snowfall last winter melted out slowly, keeping the albedo high over the NH continents and that lowered the ice volume losses this year. I'm pretty sure 2012 had less snow cover than this year and that was a factor in the record low extent.
https://climate.rutgers.edu/snowcover/chart_vis.php?ui_year=2012&ui_month=4&ui_set=2
https://climate.rutgers.edu/snowcover/chart_vis.php?ui_year=2012&ui_month=5&ui_set=2
https://climate.rutgers.edu/snowcover/chart_vis.php?ui_year=2019&ui_month=4&ui_set=2
https://climate.rutgers.edu/snowcover/chart_vis.php?ui_year=2019&ui_month=5&ui_set=2

5
Arctic sea ice / Re: The 2019 melting season
« on: August 18, 2019, 10:18:01 PM »
Weather is what causes the melting of sea ice and glacial ice and it's the initial driver of changes in sea surface heights and ocean currents. All of these things are coupled but weather is the difference between 2019, 2012 and recovery years and the sea ice, SSH and ocean currents integrate the long-term effects of daily weather.

What's interesting and disturbing about 2007, 2010, 2012 and 2019 is the tendency of persistence of weather patterns through theses melt seasons that caused intense losses of sea ice.  2012 was the perfect melt season for melting ice because it switched from hot and sunny in June and July to stormy at the beginning of August. If this year produced a GAC in the last ten days of August, it would have a chance of beating out 2012 for the minimum sea ice extent, but fortunately the forecast storms appear so far to be much weaker than the GAC.

Quantum mechanics is important here because increasing levels of man made greenhouse gases and water are adsorbing outgoing longwave (thermal) radiation and re-emitting heat downwards. Early open water in the Bering and Beaufort seas this year made the effects of high pressure over the Arctic much worse because solar heat was taken up by open water and water vapor was evaporated, reducing radiation losses. The same weather thirty years ago would not have been so destructive to the sea ice because there was thick multiyear ice over the Beaufort sea and the Bring sea was iced over. The high pressure over the Arctic that made Alaska and the Beaufort sea warm this May would have been much colder thirty years ago.

6
Arctic sea ice / Re: The 2019 melting season
« on: August 18, 2019, 03:27:28 AM »
You find those maps here:
http://bulletin.aviso.oceanobs.com/html/produits/aviso/welcome_uk.php3

They go back to 1993. There's a huge amount of information on the sea surface height maps but they are complex and not so easy to interpret.

Compare the past 2 years to 1995. Most of the increase has been caused by melting glaciers.

7
Arctic sea ice / Re: The 2019 melting season
« on: August 18, 2019, 02:30:11 AM »
Sea surface height anomalies have gone way up in the north Atlantic. It started before the big melt in Greenland with El Niño and high pressure over Greenland and much of the north Atlantic. I'm sure there's other stuff going on, too, such as Antarctic melting last austral summer.

Large sea surface temperature and ocean heat anomalies in the northern hemisphere this summer are also a factor in the high water levels on account of thermal expansion.

If you are in a coastal area you may see increased coastal storm damage this September and October because of high sea surface heights.

I don't think that the melting in Greenland has already affected tides and sea surface heights across the whole north Atlantic yet. Tides are running high in Culebra, Puerto Rico, too.

8
Arctic sea ice / Re: The 2019 melting season
« on: August 17, 2019, 09:42:48 PM »
The latest ECMWF 12Z run keeps the heat on in the Laptev sea and ESS. With continued warm air advection and persistent winds off of the Eurasian continent, the ice pack will continue to be driven towards Canada and the slowdown in extent falls will be be replaced by larger drops in extent. The recent losses in area indicate that the ice continues to melt and that persistent winds will bring on compaction and extent decreases.

The ECMWF run about 10 days ago that predicted record high geopotential heights over Alaska verified. GPH values were similar to July heights over the Colorado plateau. The European model was stunningly accurate in predicting this record event. 500 mb Heights at Cold Bay reached an extraordinary 5980 meters.

https://twitter.com/Climatologist49/status/1162537243036119041

Click image to animate.

9
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: August 17, 2019, 05:38:59 PM »
Mercator has made multiple "improvements" of their model and their data sets over the years. Every time they make an improvement the older images are removed from public access. I find it frustrating when it becomes impossible to go back more than a year or 2 to make comparisons.

Some very important things are happening in the Beaufort and other Arctic seas, but we are almost blind to what's happening because of the paucity of buoys and ships monitoring the Arctic. It's crazy that there isn't better monitoring of the Arctic.

10
Science / Re: Trends in atmospheric CH4
« on: August 17, 2019, 04:35:24 PM »
That report that fingers fracked methane may be correct but the math does not give a unique solution. There are multiple possible sources of changes in C-13/C-12 ratios. The article correctly points out that fracked gas has a different ratio that gas from traditional gas reservoirs because of oxidation reactions that take place when gas migrates to a reservoir. However, there are other possible sources that might also produce the observed change in isotope ratios. There's no bad science here but the results are ambiguous and other researchers have fingered other possible sources such as Asian agricultural activities including rice growing.

11
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: August 17, 2019, 03:22:05 PM »
The Arctic oscillation, associated with subsidence over the Arctic, has been exceptional as has the albedo warming potential.

Arctic waters have taken up stunning amounts of heat.

The GAC took heat from mid-ocean waters to melt Arctic ice. This melting season insolation and advected heat from the south has added heat to Arctic waters. So, what's exceptional about this melting season is the amount of heat added to the Arctic climate system of ocean, atmosphere and ice. There's only a very small chance that sea ice extent and area will end up lower this year than 2012, but there is little solace from that when considering long-term Arctic warming.

12
The ozone hole has caused upper and middle stratospheric cooling which has contributed to the tightening of winds around Antarctica that led to the upwelling of CDW.

Of course, there are many other variables, but the damage to the ozone layer has cooled the stratosphere at both poles in the months of polar daylight.

13
Arctic sea ice / Re: The 2019 melting season
« on: August 13, 2019, 09:02:44 PM »
They are both wrong.

And back to the point, we are in some control of where the climate heads although we cannot control the details and we are struggling to understand the complex interactions between the ocean, ice and atmosphere. It's shocking to me that the Arctic ocean is so thinly observed given its key role in earth's climate. The few buoys we have making observations of the upper ocean show heat at about 50m that the Mercator model is missing.

Careful observation of individual floes shows that A-Team is correct that the ice does not directly follow wind streamlines, sea surface height gradients or ocean currents. It is affected by all of them, plus it compresses and forms ridges. Below the surface, we have sparse measurements of the movements of water masses. We're still trying to untangle the effects of the GAC in 2012 on the sea ice because we have don't have dense enough data on Arctic ocean heat content changes through the melting season. And "we" includes the sea ice experts who don't do significantly better at predicting September extent than this ragged group of interested observers. For a variety of reasons, but mainly because we can't predict seasonal weather well, the expert's models don't work very well.

Ironic, isn't it that the one thing we do know pretty well, the effects of CO2 on paleoclimate, has been so poorly explained in this melting thread. Geothermal heat has an inconsequential effect on climate. https://skepticalscience.com/heatflow.html

Solar heat and all the factors that affect the earth's radiation balance control the climate. Greenhouse gases are among the most important controls and CO2 is the key gas over the past billion years. The modern climate is paradoxical because the sun was cooler in the precambrian than it is now. Of course, we know that declining CO2 levels over the past 25 million years led to the onset of the Pleistocene and the ice ages. Those declining CO2 levels we mostly caused by increased rock weathering rates associated with the continental collision of the Indian plate with the Eurasian plate.

So while we watch the impacts of unprecedented ocean temperatures in the far north Pacific and Atlantic oceans, and shockingly warm Arctic seas, on Arctic weather and sea ice, two proudly ignorant fools are clogging this thread with arguments that ignore the effects of CO2 on climate. Siberia is literally on fire, thunderstorms are approaching the north pole and the Arctic oscillation has been stuck in hot subsidence mode almost all summer and yet some folks here don't seem to get that rapidly increasing CO2 levels are the primary cause of all of it.

Click image to animate. The heat keeps on coming into the Eurasian side of the Arctic.

14
Arctic sea ice / Re: meaningless freezingseason/melting season chatter.
« on: August 12, 2019, 09:28:18 PM »
AWP and SST anomalies should directly correlate and it would be disturbing if there was no correlation. Obviously, there are other factors related to winds, currents and initial conditions, but the correlation looks strong this year. If that extra heat doesn't delay freezing, there's going to be a lot of heat stored below the surface of the ice. It a good bet we'll see a combination of the two.


15
Arctic sea ice / Re: The 2019 melting season
« on: August 12, 2019, 09:10:19 PM »
GFS forecast cold temperatures over open water in recent days may make sense where there is some ice left in the water. Salty ice water is something between -1.6 and -1.8 depending on salinity. However, I'm suspicious of some of those GFS temperature forecasts over open water.

Overall, the European model indicates strong warm air advection and melting in the Laptev area and continuing retreat of the ice pack on the Siberian side over the next week. We should look out for a shift towards lower pressure in the central Arctic. It's about time that some of the lows in the polar seas on the Atlantic side head into the central Arctic. We'll see. Bothe the GFS and ECMWF hint that we might see that ten days out.

16
Arctic sea ice / Re: The 2019 melting season
« on: August 12, 2019, 06:31:28 PM »
Summer stratospheric dynamics have changed drastically since 1979. The combination of ozone loss in the upper stratosphere and warming of the lower atmosphere have enabled a shift to negative Arctic oscillation index values in the summer. 2019 is the most persistently negative AO of any summer since 2019 that I have seen. It's shocking how different the cross section of thermal anomalies over the pole was in the early 1980s.

This (combined with many other studies) leads me to think that the loss of polar ozone played a role in the loss of sea ice since 1979 and now the  loss of sea ice is feeding back creating a large shift in atmospheric dynamics.

17
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: August 12, 2019, 03:07:08 AM »
The ponds drain and when the sun angle gets at it's lowest or twilight comes, depending on location, the exposed ice surface firms up. That's what happens after 10 August in much of the Arctic. There's still a shockingly high amount of heat in the ocean and temperatures are still, on average above freezing.

The warm air advection is keeping the ocean temperatures well above normal and when winds, waves and ice motion causes the warm water to interact with the ocean water, ice melting continues at a good clip.

This summer may be worse than 2012 for the long term condition of the ice because heat is building up in the mid levels of the Arctic ocean, not being extracted by a long lived intense storm.

Interpretation of area and extent data is difficult when the Arctic is so cloudy. We are likely seeing the effects of cloud artifacts. The draining of melt ponds and compaction has caused NSIDC area measurements to stall, but that doesn't mean that melting has stopped.

18
Arctic sea ice / Re: The 2019 melting season
« on: August 11, 2019, 01:56:21 PM »
I've always hated margarine.

Early heat is necessary to have a strong melt year. That's what's going on with the pretty similar curves. The rest is either coincidence or a function of the geography of the Arctic and surrounding seas. Geographical controls are important to the evolution of the melt season.

19
Arctic sea ice / Re: The 2019 melting season
« on: August 10, 2019, 04:50:14 AM »
Sark, Zach Labe's group (he's a grad student, not the prof that heads the group) has several recent papers including one by Zach. Ocean heat in the Barents sea, where ice used to be, strongly affects winters with westerly winds in the middle tropical stratosphere. However, this effect of upward wave propagation is very weak in the early fall. Therefore, there's a pretty good chance that we will see a shift to low pressure over the pole in September or October.

It works that way because westerly wave energy won't propagate upwards through easterly winds in a dome over the pole in the lower stratosphere so the upper stratosphere will cool as soon as insolation drops in September. Thus a strong polar vortex will begin to form in the upper stratosphere above the subsidence dome. That will work its way down as fall gets going.

20
Arctic sea ice / Re: The 2019 melting season
« on: August 09, 2019, 03:35:27 PM »
I post 6 to 10 day forecasts when the models are indicating a large scale phenomenon such as a a change in the Arctic oscillation. I know that the models are unlikely to get the details right and will the ECMWF often overdevelops storms and ridges near the pole in those forecasts, but I find that the European model does pick up large scale features pretty well on the 5 to 10 day scale.

We have reached the point in the melting season where bottom melt dominates and heat in the ocean has more impact than insolation in the central Arctic. There is sufficient ice around the pole that we can now be certain that there will be no "blue ocean event" this year.

21
Arctic sea ice / Re: The 2019 melting season
« on: August 08, 2019, 09:03:20 PM »
Subsidence and high pressure that focused on the "ridiculously resistant ridge" in the northeastern Pacific ocean has moved north to Alaska and the Arctic over the past year. The ECMWF continues to forecast heat pumping out of the Pacific into the Arctic. The latest model run shows typhoon heat and water vapor being pulled into troughs that wave break into the Arctic, creating a massive Arctic heat anomaly. It's nuts.

This has been the most persistent ridging/subsidence pattern of any Arctic summer in the Climate data center set of stratospheric "paint drip" maps that I have reviewed. The high pressure and high geopotential heights over the Arctic have been relentless.

22
Arctic sea ice / Re: The 2019 melting season
« on: August 08, 2019, 01:06:39 AM »
The ECMWF has been consistent for several days in developing the converging Asian, Atlantic and Pacific ridges aloft. It has handled these blocking situations better than the GFS in the past, but honestly I don't have a clue about this version of the GFS yet.

The latest 240 hour Euro prog has a full on subtropical summer airmass thickness over the Bering strait. Heights of 594mb are pretty typical over the Colorado plateau in midsummer. They don't belong over the Bering sea.

For the past year we have seen amazingly intense blocks over the Bering strait but if this one verifies it will be the block that gives Santa Claus a Hawaiian vacation at the pole. It is one of the most outrageous forecast outputs I have ever seen.

23
Arctic sea ice / Re: The 2019 melting season
« on: August 06, 2019, 11:17:08 PM »
7-2-1 Shows clouds clearly and meltponds show up as a deep blue. Today we can see that the sea ice north of Greenland and Ellesmere Island is covered with deep blue melt ponds and the temperatures are likely unseasonably warm for so late in the melt season. Active strong surface melting continues between the CAA, Greenland and the pole. The deep blue on 7-2-1 is indicative of that active melting.

24
Arctic sea ice / Re: Latest PIOMAS update (August 2019)
« on: August 06, 2019, 03:42:08 PM »
That highly anomalous steepening of the volume curve in mid-August 2012 is best explained, in my opinion, by Ekman pumping of heat from the Atlantic water layer into the surface ocean. Normal storms can't do this because they don't persist long enough to break up the strong density inversions. The GAC lasted ten days and was very intense at its peak. It was strong and persistent enough to break down the layering in a large volume of the Arctic ocean.

The buoy profiles were stunning. Ekman pumping by persistent high pressure areas has caused multiple episodes of upwelling along the continental shelf in the Beaufort sea, but I'm not aware of any storm other than the GAC causing a upwelling of mid-ocean water in the central Arctic ocean. There was a very large amount of energy involved in the rapid melting of ice in mid-August 2012. Because there were not large amounts of heat advected by the atmosphere, it must have come from the ocean.

This melting season atmospheric heat advection may be larger than it was in 2012, but so far storms are not persisting like the GAC, so we should perhaps expect less bottom melt from ocean heat than took place in August 2012. However, sea surface temperatures in the Arctic are very high this summer so there is a lot of ocean heat in the upper layers. Moreover, strong atmospheric heat advection has been persisting in the Arctic for months. We are going to get a chance to compare the effects of different processes on the melt minimum by comparing 2012 and 2019. The sea ice volume curves are a most important aspect of that comparison because they are a function of system enthalpy (heat).

25
Arctic sea ice / Re: The 2019 melting season
« on: August 04, 2019, 04:15:58 PM »
Except for an area of the northern Barents sea between Svalbard and FJI which has been cooled by advection of ice into the waters, SSTs are anomalously high on the Atlantic side. Anomalies on the Atlantic side were higher in 2012 when there was less advection of ice into the northern Barents sea but 2012 was exceptionally warm in Greenland and the Atlantic side of the Arctic.

SST's this early August are shockingly high in the northern hemisphere and the anomalies are largest in the northern regions of the NH oceans and seas.

All this ocean heat is increasing the tendency for atmospheric blocks to form and it's increasing atmospheric advection of heat into the arctic. That doesn't mean that extent will be lower this September than in 2012 but it will be a major factor in low sea ice extent this September.


26
Arctic sea ice / Re: Latest PIOMAS update (August 2019)
« on: August 04, 2019, 04:02:50 PM »
This year the transpolar drift has been strong and Fram export has been high compared to the last decade. The lack of Fram export in July has become the new normal as warm salty Atlantic water pushes back into the ice pack melting ice out before it reaches the Fram. There's also a summer seasonal tendency for winds that don't favor Fram export. That doesn't mean that export hasn't been high this year. The relatively high ice thickness on the Atlantic side of the basin is evidence of the strong transpolar drift that has affected the ice this year.

27
Arctic sea ice / Re: The 2019 melting season
« on: August 04, 2019, 12:34:33 AM »
I was expecting to see heat flowing into the Arctic after the deep Urals trough formed. I was surprised when model runs a few days ago didn't predict it. Today's model runs make sense and are consistent with weather patterns we have seen all summer. There is still very hot weather in south central Asia and that heat is being blown towards the Laptev sea.

Expect the Laptev bite to expand in a big way over the next ten days.

28
Arctic sea ice / Re: The 2019 melting season
« on: July 31, 2019, 01:40:27 AM »
Worldview has much better resolution than the little JAXA image. Yes, it has clouds but you can look at many days to see what's happening. And seaice.de has higher resolution and uses similar input as JAXA.

Looking at all of those sources and PIOMAS, I think it's pretty much a dead heat between 2012 and 2019, but the GAC tapped into ocean heat down to the Atlantic water layer according to buoy data. It's going to be hard to top the effects of the GAC because of the heat it tapped into, but then again it's still July and who knows what will happen in the next six weeks.

29
Arctic sea ice / Re: The 2019 melting season
« on: July 30, 2019, 04:43:53 PM »
Zach Labe aka "Blizzard" on this blog has a recent paper on the effects of sea ice loss on the atmospheric circulation. It turns out that the QBO, an alternating pattern of tropical westerly to easterly winds and back in the mid-stratosphere affects the atmosphere's response to the lack of sea ice in the Barents - Kara sea region. That means that there will tend to be alternating Arctic oscillation anomalies from one year to the next.

There's other stuff going on, especially the transport of heat into the Labrador sea region and the effects of melting ice on the overturning circulation in the subarctic seas. Pulses of ocean heat are followed by increased amounts of meltwater. This effect helped the Arctic ice recover after the very bad years for ice from 2007 to 2012. Unfortunately, another pulse of heat is now slamming the ice.

A cool pool formed in the subpolar gyre around Greenland after the extreme melt years of 2010 and 2012. Storms in the summer kept it from being hidden by a thin layer of warm fresh water.

High pressure over Greenland this summer has coupled with the return of warm water into the Labrador and Greenland seas. The cool anomaly has pushed south to the storm track across the Atlantic.

A reduction of particulates in China is not driving the patterns we are seeing now in the Arctic as far as I know. We just had a weak El Niño which has caused global temperatures to rise. A reduction in particulates in Asia will have effects on the atmospheric circulation over longer time periods but I think they are lost in the noise of El Niño on the scale of one or two years.

I expect increasingly erratic weather from one year to the next and on longer time scales as ice melts and the ocean and atmospheric circulation patterns respond to melt pulses.

30
Arctic sea ice / Re: The 2019 melting season
« on: July 29, 2019, 03:08:25 PM »
That overlaid bathymetry map shows the impacts of the subduction of heat in the Beaufort sea and the Nansen basin. The "Atlantification" of the Nansen basin is one of the major changes that has been taking place in the Arctic over the past 15 years. The new and very disturbing thing we're seeing this summer is the collapse of thick ice north of Ellesmere Island and in the Lincoln sea. I've looked on Worldview back as far as I could go and this summer is far worse around Ellesmere than any other year. It's hard to predict what this area will look like in September because this situation is like nothing we've seen before.

31
Crandles, the increase in heat transfer from the ocean to the atmosphere when ice is thinner does not "net off" in terms of heat in the atmosphere. Yes, most of that heat eventually radiates out to space but before it does fall and winter temperatures in the Arctic are pushed upwards. The effects of less ice in the Bering, Chukchi and Beaufort seas have been pronounced over the past 5 years in Alaska. They have had several extraordinarily warm winters and late falls.

The ongoing build up of heat in the summer water layer in the Chukchi and Beaufort seas indicates that there is carry over from one warm summer to the next.

Obviously, the researchers simplified the problem so we should be careful about overextending the results, but your criticism misses some key issues about the build up of heat in the Arctic ocean/ice/atmosphere system.

32
The forum / Re: How many of you are scientists?
« on: July 26, 2019, 02:49:17 AM »
Geology - undergrad.
Geochemistry - PhD
Weather geek since I was a little boy.

I worked professionally on nuclear waste research. Retired now.

I agree that a number of employed posters may want to keep this forum and their private lives separated. Things are crazy in the U.S. and they also look pretty messed up in the U.K to me.

33
Arctic sea ice / Re: The 2019 melting season
« on: July 26, 2019, 02:06:00 AM »
The channels of the CAA wil get a steam cleaning over the next 10 days southeasterly and southerly winds are going to drive ice out of the north side of the channels into the Arctic while the southern sides of channels melt out completely. This pattern is worse for the CAA than Greenland because of the persistent warm southerly winds.

The ice just north of the CAA already looks like a fallen mirror shattered into tiny fragments. We'll get to see how thick it is after 10 days of getting blasted by s subcontinent sized blow dryer.

34
Arctic sea ice / Re: The 2019 melting season
« on: July 25, 2019, 05:00:36 AM »
I suspect that melt ponds lasted later in July before the year 2000. The thick multiyear ice would have kept its below -1.5C temperatures longer into the melt season supporting melt ponds later into the year.

I think that explains the paradox of 80N temperatures being lower after Y2k than prior to it. Melt ponds support warmer surface temperatures. An saltwater ice mixture supports negative 1.5 C temperatures at the surface.  The effects of solar heating and atmospheric heat may lead to a higher 2m temperature. The paradox is that melt ponds over thick ice support higher 2m temperatures than drained melt ponds over ice that's almost melted out.

Observe that there has been a significant dip in temperatures the past few days, but 80N to the pole is still above freezing on average.



Yes, I'm sitting in a dining room chair in North Carolina. It has been sweltering here but today we got relief from a cold front that passed through. I am very frustrated by the paucity of data out of the Arctic. I know that my hypotheses could be wrong and would like more data.

35
Arctic sea ice / Re: The 2019 melting season
« on: July 25, 2019, 03:03:56 AM »
A stunning amount of heat is forecast to affect the American side of the Arctic ocean. It's apparent in the ECMWF 850mb progs and it's apparent on the GFS 2m progs. Some folks here just don't get that an icewater system doesn't have big thermal anomalies near the surface because it sucks up heat like a huge sponge.

Larger anomalies are possible on the Siberian side of the Arctic in late June and early July after all the snow is gone in Siberia. It's a warm air advection off of land thing.

A main cause of Arctic amplification is water vapor and warm clouds advected from the north Atlantic and north Pacific, but northern Siberia when it gets warm and wet in late June and early July is another potential source of OutgoingLongwaveRadiation reducing water vapor and clouds.

36
Arctic sea ice / Re: The 2019 melting season
« on: July 24, 2019, 07:08:07 PM »
Thanks Hopen Times for the correction concerning the icebreaker.

Open water is showing up on the north and east sides of the Parry channel now and ice movement can be seen on RAMMB slider. Ice in the southern channels is melting and ice from further north is getting compacted into the southern channels. I wasn't able to tell if the whole Parry channel had moving ice, but the ice is in very bad shape now.

And yes, this has been a very bad year for multiyear ice. The Nares strait was open all year. The brief arch in the Lincoln sea was maintained for a month by winds that sent ice towards the Fram strait, not the Nares. That did not help maintain thick ice. When high pressure returned in May the Beaufort became a thick ice killing zone. I expect a record minimum volume in September with little thick ice remaining.

37
Arctic sea ice / Re: The 2019 melting season
« on: July 24, 2019, 03:57:24 PM »
The observations from the icebreaker are consistent with PIOMAS and ice drift maps. The strong transpolar drift this year has pushed ice towards the north coast of Svalbard and the Fram strait. The presence of multiyear ice in that region is not good news because that's ice about to be melted by warm Atlantic water.

Ice ridges would make crossing the ice that piled up north of Svalbard difficult to cross by icebreaker. The captain rightly turned back to protect his ship and his passengers, but that does not mean that Arctic ice is in good shape this summer. It means that some of the thickest ice is being exported out of the Arctic.

38
Arctic sea ice / Re: The 2019 melting season
« on: July 22, 2019, 04:08:56 PM »
Mercator doesn't show evidence of much heat in that saline 30m water. The salinity, alone, will impact melting, however. Thanks for the outstanding animations, Uniquorn. That observable information shows that the Mercator model is pretty damn good in that region despite the paucity of data. Mercator's color gradients are not subtle enough to help us track Atlantic water heat that's possibly contributing in melting the ice.

In 2012 waters were warmer in late July on the Atlantic side but cooler on the Pacific side. Warm air advection into the Arctic from air masses originating from above these above normal temperature waters may play a major role in the late summer melting season. The forecast dipole pattern will import anomalously warm humid air from the Pacific.

Note that the cold water pool that was located southeast of Greenland for several recent years is gone, replaced by warm salty Gulf Stream water. The thermohaline circulation has recovered from the effects of the big Greenland melt years of 2010 and 2012.


39
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: July 22, 2019, 03:06:54 PM »
What trends in the central Arctic. What we're seeing is a series of downward steps at irregular intervals. Those steps are related to the polewards advance of warm water and warm air in the north Atlantic and the intensification of El Niño with the heating of the planet. Surges of warm salty water into the Arctic from the north Atlantic have been irregular, but they involve large amounts of heat so they have a pan Arctic impact.

Forget about drawing lines and curves through irregular steps to make a forecast. We need to understand the steps better or we need to use a model that has stochastic elements.

Yes, the IPCC and governments have been doing abysmal risk management. There are huge weather and climate impacts of the polewards movement of ocean heat apart from the issue of an ice free Arctic in September. We are already seeing those impacts but they will get worse even if we do everything right to cut GHG emissions because of the earth's energy imbalance caused by thermal disequilibrium with the middle and deep oceans.

40
Arctic sea ice / Re: The 2019 melting season
« on: July 22, 2019, 04:26:39 AM »
The basic dynamics of the atmosphere have not changed but the Brewer Dobson circulation - the movement of air and energy from the troposphere to the stratosphere and back down - has intensified. Zach Labe is studying aspects of this problem and knows the physics far better than I do. I could be getting something wrong because this is far beyond my training in physics, but it appears to me that this year has had the most stratospheric subsidence heating the polar atmosphere of any year we have been observing it with scientific measurements.


41
Arctic sea ice / Re: The 2019 melting season
« on: July 21, 2019, 10:09:21 PM »
I suspect the worst pattern for ice at this time of year is the dipole pattern with low pressure in the ESS and high pressure over the CAA and Greenland. It favors the export of sea ice, the mixing of ocean heat with ice and intense melting of ice in the passages of the CAA.

42
Arctic sea ice / Re: The 2019 melting season
« on: July 21, 2019, 10:03:05 PM »
There's a strong persistent dipole developing in the ECMWF that will last through the 10 day forecast period if it verifies. The heat and subsidence will continue over northern Canada and Greenland until further notice.

This is the weather that will put 2019 ahead of 2012 if this forecast verifies and I think it will because it is consistent with climatology and persistence of this summer's weather patterns.

FYI, the 850 temps we have seen in the past week do not indicate negative heat balance as far as I know. In some areas they indicate rising motions over the ice water. Clouds over these areas would have limited radiative heat loss and loss of energy from the ocean/ ice system. Warm air advection has been strong in the Kara sea over the past few days. Over all that has kept temperatures above freezing in most of the Arctic and has led to continued flow of heat from the atmosphere to the ice on average in the Arctic.

43
Those gravity studies of Antarctic geology are very interesting to me. It appears to me that the WARS is not inactive, but similar to the tectonic situation in the Arctic ocean where there's very slow spreading along ridge segments.

It's impossible to do typical GPS land based tectonic studies there because the ice moves much faster than the rifting. However, the ongoing volcanic activity, while not definitive, is evidence supportive of ongoing activity along the long rift/transform fault system that crosses Antarctica.

Of course, this tectonic situation is relevant to glacial melting, isostatic adjustment and sea level rise. This rift zone will be a potential region of increasing volcanism as glaciers retreat and depressure deep magma reservoirs. Yes, this is a potential positive feedback.

44
Arctic sea ice / Re: The 2019 melting season
« on: July 19, 2019, 05:53:09 PM »
The discussion of the DMI thickness model has devolved into personal insults. The horse is dead and has been beaten multiple times. That arm in the ESS, real or not, will not make it through the next month. Likewise, the thick ice floes in the Beaufort sea will melt out as they move about in the sunshine-warmed water. The ongoing personal arguments will amount to exactly nothing in a few weeks.

The people involved in the personal insults are destroying their public reputations on this forum over precisely nothing.

45
Antarctica / Re: SH Polar Vortex
« on: July 19, 2019, 03:40:14 AM »
I think that your concerns about fire are justified. Places with Mediterranean climates have fire problems that have gone from bad to worse. Spain and Greece, California and Australia have all had extreme fire storms in recent years that are worse than they used to be because of warmer and drier weather.

46
Arctic sea ice / Re: The 2019 melting season
« on: July 17, 2019, 07:32:02 PM »
Take your time with family, Neven. I'm so sorry about your loss. We'll carry on here.

47
The forum / Re: Forum Decorum
« on: July 17, 2019, 07:09:20 PM »
Gerontocrat, I will go after trolls, Nazis, white supremacists so that you can stick to your detailed accounting of regional area and extent. I feel bad the BL left because we can deal with the alt right evil, but it takes time.

My apologies to every decent person in the world who is horrified as I am about what the USA is doing to refugees and asylum seekers. I am ashamed and disgusted by the illegitimate regime in the White House.

FYI, I look at the political threads here very infrequently.

48
Antarctica / Re: SH Polar Vortex
« on: July 17, 2019, 06:03:32 PM »
The SH polar vortex has been impacted by the loss of ozone in the upper stratosphere, especially in the early spring. Cooling at high levels by the loss of ozone caused a tightening of the vortex and may also be causing instabilities such as sudden stratospheric warmings which are not common events in the SH.

For more details you need to read papers and reports by actual meteorologists. Paul Beckwith is not a good information source for Antarctic meteorology. The combined effects of ocean heating and ozone loss are affecting Antarctic weather, but it's very complicated because it also involves ocean currents, fresh water layers and deep convection of cold salty water. Hansen's papers get into some of the complexities of climate change in Antarctic waters. Hansen is a legitimate expert on atmospheric physics.

49
Arctic sea ice / Re: The 2019 melting season
« on: July 17, 2019, 04:58:55 PM »
The concentration is dropping because temperatures are above freezing. With these temperatures, it would be dropping if high pressure were in the areas that are stormy. Moreover, in areas such as the Lincoln sea, there has been strong warm air advection and wind flow.

Temperatures over the Arctic ocean continue to be above normal. These warm temperatures should continue to cause above normal rates of melting.

50
Developers Corner / Re: Test space
« on: July 17, 2019, 04:52:40 PM »
I sympathize with A-Team's frustration concerning the melting season discussions. Except for Nico Sun's albedo warming potential, which has shown some promise for guiding predictions, there is no skill in September minimum forecasts. To make a skillful forecast it is first necessary to predict weather over a month out. Of course, that's no all that's needed, but because it's impossible to do that all of the September forecasts are at best ways of testing our models and ideas. Generally they are entertainment without scientific content.

There is far too much noise in this year's melting season threads.

I don't blame people with bad intentions, although there have undoubtedly been a few trolls. This place has become popular and people who have little or no content to add get excited and jump in with emotional content. That's human nature, I guess. So this place is a victim of an interesting year and the success of this forum in grabbing a large audience.

There is no easy answer to this problem. Creating a thread for expert posts would cause its own set of problems.

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