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Messages - Michael Hauber

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1
Arctic sea ice / Re: The 2019 melting season
« on: June 21, 2019, 12:27:00 PM »

My understanding was that high pressure means clear skies so high insolation. But is 1040 hpa worse for ice than 1030 hpa, all else being equal ?

Larger high pressure means either colder denser air (the strongest high pressures on earth are ultra cold air over Siberia), or a stronger upper ridge.  If its a stronger upper ridge it means stronger descent of air, and air heats up as it sinks.  This high has a strong upper ridge associated with it.

2
Arctic sea ice / Re: The 2019 melting season
« on: June 21, 2019, 01:46:24 AM »
850hp air temps over last 7 days:



I had a look at 4 weekly periods (1st to 7th, 8th to 14th, 15th to 21st, 22nd to 28th) from each of 2007,2010,2011 and 2012, being years I remember having strong surface melt in June.  Hottest I could find was 2007:



3
Arctic sea ice / Re: The 2019 melting season
« on: June 20, 2019, 06:34:30 AM »
Michael Hauber. If there's a real increase in area in the Beaufort Sea it came from elsewhere, there's no new ice forming. It came from the CAB, which hasn't had an area reduction, so trhe concentration has to have decreased.

Definitely came from CAB..  CAB has not had a decrease in area detected by incidents - therefore concentation as measured by instruments did not decrease.  Two possibilities.  The ice moving from CAB to Beaufort was replaced.  Current weather patterns suggest that ice from Laptev is moving towards the CAB, so I am sure this accounts for at least part of the reason why the CAB did not lose area.  Its also possible that CAB lost real area, but this was not detected by instruments.  I can't see anything on MODIS, but thats no guarantee.  Either way there is no contribution to dispersal as measured by instruments due to this effect.

4
Arctic sea ice / Re: The 2019 melting season
« on: June 20, 2019, 02:25:29 AM »

Quite a little cyclone this created! As others pointed out, the primary reason is clear in the data: dispersion. E.g. Look at Wipneus' regional extent charts for the Beaufort.


And what is the reason that Beaufort extent jumped quickly up? A storm dispersed ice from a compact region into open water --  see any of the several recently posted animations of the region. The end result of this dispersion will almost certainly not be less ice melt, but more.

I realize that all this has been pointed out previously, but I agree with TeaLight and just want to make sure that these obvious points have not been obscured successfully.

Don't hang your hat on extent values, especially short-term blips.

Look at both the extent and area charts for Beaufort.  They both jumped up.  So not more dispersion, just more ice in general in that location.  Recent weather patterns have been pushing ice from Laptev direction (where rapid ice loss is evident) and towards Beaufort.  If you compare concentration maps of today with those a week or so ago the obvious increase in low-concentration ice is around Laptev and ESS, and corresponds to melt ponds.

I put zero importance in short term changes in extent, but do suggest that they be attributed to the correct reason, being cloudy weather in Kara delaying ice melt in that region for a short period of time.  The region will melt out soon enough, and slow melt in Kara is due to cold air being exported from Arctic in that direction allowing warm air to move into the Arctic from elsewhere.

5
Arctic sea ice / Re: The 2019 melting season
« on: June 19, 2019, 12:50:30 PM »
Following the recent accusations directed at me, Neven suggested I state that I am concerned about AGW, do believe the ice is melting.  I believe that the IPCC reports are the best scientific assessment of what is likely to happen in the future.  I also accept that there are serious risks associated with climate change.  While I believe it is unlikely that impacts of climate change will be dramatically worse than what IPCC predict, I believe that the low possibility of such extreme aspects should be taken into consideration, and we should act strongly on climate change to reduce the risk of nasty surprises.

If some are surprised by the intensity of the reaction to my recent comment, my opinion is that the intensity was motivated by past arguments that I have pursued very strongly in the consequences section of this forum, especially around claims that IPCC is seriously understating the risks. 

6
Arctic sea ice / Re: The 2019 melting season
« on: June 11, 2019, 08:54:27 AM »
A tale of two Arctics.  Warm air has pushed into Siberian and Laptev sectors in a big way with serious surface melting.  Beyond that the Arctic is mild with minimal surface melting.  Beaufort amazes me with many large floes and little to no small floes - Little visible sign of melting but plenty of open water.

Forecasts show a strong temperature contrast with the coolest air still at -8C at 850HP according to GFS, and the warmest air above +12C.  Definitely one of the larger temperature contrasts I've seen.

7
Arctic sea ice / Re: The 2019 melting season
« on: June 05, 2019, 01:17:46 AM »
June 4 Channel 3-6-7.  Significant amount of red showing in Laptev area.  I'd say 2012, 2015 and 2016 all have more red (Arctic wide) as at June 4 than 2019.  Hard to be sure about 2012 due to cloud cover, but given the events of that year I'm more bullish guessing on red below the clouds for that year.  Red reflects surface melting.


8
Arctic sea ice / Re: The 2019 melting season
« on: May 24, 2019, 01:32:41 AM »
For those interested in what happened in the Beaufort, back in 2016 (so as to compare to this year's siutation), I wrote about it extensively on the ASIB. Here's a blog post from May 21st, with links to previous blog posts in the first paragraph.

The maps look very similar, so much so that one would be tempted to think there is something causing the ice to stay glued to the coast, all the way up to Utqiaġvik. But there's no "Chukchi polynya" now, with open water all the way to the Pacific and far into the Chukchi, meaning there is less ice to be blown back towards the coast, should the winds turn.

And the winds are another similarity. Both the weather forecast back then and the one this year show a change in the set-up that caused the early Beaufort opening, around the same time. However, this year there may be a return to that set-up next week.

So, wondering if there will be open water all along the Alaskan-Canadian coast before July this year...

My guess there are two factors behind this 'ice bridge'.  First there seems to be more fast ice on the coast - presumably the sea bed is shallow and/or perhaps currents favour colder water below the ice.  Second I suspect the beaufort gyre and shape of the coast line combine.  Ice I think tends to move away from the coast towards Chukchi and towards CAA, but towards the coast near this ice bridge.  As soon as temps warm enough that ice can't form these two areas become ice free as ice moves away from the coast, but the ice bridge area needs temps to warm enough that substantial ice in the Beaufort at large is melted and there is no longer enough ice to move towards the coast.



(using paint so hard to get a nice curve to better illustrate the ice flow)

9
Arctic sea ice / Re: The 2019 melting season
« on: May 23, 2019, 12:05:05 AM »
Here is a recent photo of sediment.



From Cat 6 blog.

Of course not all sediment will look exactly the same.

10
Consequences / Re: Weird Weather and anecdotal stories about climate change
« on: November 29, 2018, 02:22:38 AM »
The Sydney floods (plus gales and hail and fairly cold conditions, none of which were exceptional but still unusual), Intense heat in Cairns, serious bushfires, dust storms yesterday, dust storms mentioned a week or so ago in this thread.  All related to the same pattern of an unusual sequence of low pressure systems through Australia and out into the Pacific, which may be related to Southern Polar Vortex issues.

11
Antarctica / SH Polar Vortex
« on: November 23, 2018, 06:34:28 AM »
Also posted in weird weather thread in consequences.

Furthermore there is a remarkable string of strong low pressure systems belting across Australia and well into the Pacific.  Got some members of the weatherzone forum scratching our heads not sure what to make of it.  The pattern might have implications for ENSO, as I think its part of why a significant WWB is forecast to commence shortly.

I've been doing some hunting around to see if I can explain it as some sort of polar vortex variation.  Due to this forum I know more about the northern polar vortex than the southern which impacts on my weather.  Of course Antarctica hasn't had no real trend towards reducing sea ice, but has had a couple years of fairly low values.  Start of a similar change in SH to what has happened in NH?  Maybe some connection to changes in the Ozone hole....

Does anyone follow the SH polar vortex much and know if anything is going on that might explain part of this weird weather?

12
Arctic sea ice / Re: The 2018 melting season
« on: September 04, 2018, 11:33:26 PM »
Not sure if this is the correct thread; forgive me if it is not!

What happened to the predictions of a GAC from the last week of so?

There is still a pretty decent cyclone going on around Laptev/Barents.  Not far off the intensity forecast a while back.  Pretty large system getting up towards the GAC 2012 size, but a fair gap in intensity.

The forecast Friv and I commented about just a day or so ago of a huge heat influx has moderated.  The forecast had a perfect alignment of strong high and low plunging a strong warm front in between directly into the Arctic.  The alignment has shifted a bit and the warm front now strikes a fairly glancing blow.  Until the next model run....

13
Arctic sea ice / Re: The 2018 melting season
« on: August 29, 2018, 11:01:54 PM »

I don't think it is fair to say this year was GAC-less, the June event was about as impressive as 2012, it just happened far earlier in the melt season.

The June event was close when considering minimum pressure.  Not very close when considering size of circulation, or duration.

14
Arctic sea ice / Re: The 2018 melting season
« on: August 29, 2018, 12:02:07 AM »
MODIS 3-6-7 channel shows nearly total cloud cover of the Arctic, but what shows in between the clouds suggests that the surface is mostly frozen and that the surface melting season is mostly over.

A thought on the current cyclone, forecast to continue for the forseeable future.  SSTs are close to their seasonal max now, mixing and winds will cool them faster (but clouds keep the heat in).  But mixing may also push some of the heat below the surface to impact the start of the freeze season.  In contrast if the heat is left undisturbed near the surface in calm conditions it might be lost much quicker as Arctic night falls.  Ekman pumping will produce upwelling mostly in the central ice pack and presumably this will need to be balanced by downwelling somewhere in the Arctic fringes which might also push heat below the surface.

15


Even volume? Even volume? You are aware the world does occur in 3D, right? How could you prefer extent more than volume?

I think I explained it just fine in my last post.  Is there some part of it you didn't understand.

There is a place for it, but the top indicator has to be volume...cuz it is, like,  the actual amount. Takes a certain amount of energy to melt a certain volume of ice.

Winter maximum isn't about melting ice, it is about conditions being cold enough for sea water to freeeze.

Speaking of madness...saying "well this is what is going to happen cuz a  few models say so..." is effectively like pontificating about what would happen in a zombie outbreak cuz thats what happened in Fortnite or Call of Duty waves. How good do you believe the models are? Can any models tell me what the weather will be like in a month?

Climate deniers don't like what the models say so run exactly the same argument.  Seems you don't like what the models are saying and so are running exactly the same argument.  This is a science based forum and not Watts Up with That.  The models are certainly imperfect, but whats a better method for predicting the future? 

16

How does the model maintain the cold halocline layer despite the lack of sea ice cover?

You're talking about a model of arctic sea ice decline, not a model of a blue ocean event.  We have no clue what that looks like, but the hypotheses floating around suggest papers in the next couple of years that begin to test the subject.  Models of arctic sea ice disappearance may be able to be sourced in such discussions right about the time it's happening right in front of our eyes.

I'm sure the model programmed by Arctic experts does a better job of predicting the influence of the cold halocline on sea ice than the guesses of members of this forum.

17
Ice free in winter is not going to happen in the next few centuries.


18
Arctic sea ice / Re: The 2018 melting season
« on: August 04, 2018, 12:47:30 AM »
Quote
Even after a summer BOE, ice will still form in the Arctic during the dark, polar winter for many decades
So, this being merely 2018, it surely follows that Svalbard-FJL-SZ corridor froze over this winter?

Except it never came close. And this year was only a continuation of a long-term regional trend, not a variational swing attributable to unusual weather, cycle, oscillation, phase or teleconnection event.


Big difference between this region with deep water, and directly in the path of one of the warm currents from the Atlantic.  Compare to say Laptev with shallow shelfs and no direct exposure to warm Atlantic waters.  I note also that in this corridor the edge of the ice is pretty much in the same spot as it was at maximum.  Not exactly representative of general Arctic sea ice behaviour.

19
The current Arctic cyclone has been quite intense.  968 vs 963 for the GAC.  Looking at Canadian Analysis charts it covers only a fraction of the Arctic basin, compared to GAC covering the majority.  However the squeeze against the high pressure towards the Siberia Sea looks to have produced tighter wind gradients and presumably stronger maximum winds than the GAC, but over a relatively small area.

What struck me with this cyclone is the intensity of the associated warm air mass over Siberia.  After the central Arctic has generally been a little on the cooler side (compared to recent years, but still warm compared to longer term stats).  Temperature contrast plays a big role in cyclogenesis.  And while much has been said about Arctic amplification, and warm arctic cold continents, I think the situation may be reversed in summer.  During summer, particularly early summer the Arctic is still dominated by ice. This pins the surface air temperature close to 0 and the basin is pretty similar to what it was several decades ago.  The surrounding regions are getting warmer, thus we have warm continents, cold Arctic, and increasing frequency/intensity of Arctic cyclones.

And some seasons we see a transition from strong high pressure dominated weather early in the melting season to low pressure dominated weather.  2010 and 2011 really stood out as seasons that early on had severe melting weather, with some dramatic (at the time) early season stats, but then fell flat quite significantly as cyclone dominated weather took hold.  2013 was the year of the persistent arctic cyclone where the cyclones started early and just kept going.  While the surface temperature may be pinned close to 0, the atmosphere above has been getting warmer (eg 925hp temps).  But when we get a significant cyclone, mixing of the air column with the surface pinned at 0, plus clouds etc result in the relatively cool surface extending through a more significant portion of the atmosphere, thus increasing the warm continent cold arctic temperature contrast and making further cyclones more likely.

So negative feedback.  But perhaps only sometimes.  In 2012 we saw both early season cyclones that failed to establish a more persistent cyclone shield, but spread the ice and allowed intermittent high pressure weather to pump lots of heat into the mix of ice and open ocean, and then the very severe GAC.  The GAC was of course followed by massive loss of ice, although there is an argument that the ice had already been set up to melt by previous conditions and the GAC played a relatively minor role.

20
Arctic sea ice / Re: Don't read this thread
« on: July 10, 2018, 03:24:27 AM »
Took me a while but I eventually read this thread, and was amused. 

Maybe if the thread was titled '10 reasons why you must read this thread - no 7 will blow your mind' I would have refused to read it.

21
Arctic sea ice / Re: The 2018 melting season
« on: July 04, 2018, 05:08:15 AM »
Whatever the final outcome will be, I'm fairly sure that we'll see an early September minimum this year.
Why? Early summer minima are due to cloudy weather (while the sun still shines). If there are open skies, there won't be an early freeze onset. So what is convincing you of the contrary?

Not sure what Lord Vader's reasoning may be, but I think we might be biased towards an early minimum because the core ice has been somewhat cooler and the fringe ice much warmer.  So late in the season the easy to melt ice will be gone and whats left will be stronger.  Still my personal opinion is that the weather near minimum would be more important.

22
Arctic sea ice / Re: The 2018 melting season
« on: July 01, 2018, 09:57:56 AM »
Here is 6/19-28 2018 minus 2012. I would call this severe abrupt and apocalyptic climate change. We have clearly hit an inflection point re: continental albedo and sea ice. Maybe the Mayans were right after all and this occurred in 2012?  :o

Also ^ data directly refutes the notion that the weather has been beneficial to the ice. It has been the worst June on record.



Two points.  Firstly there are no direct observations of surface temperature in the arctic,  the output is not observational data, but a weather model output.

Secondly 19th to 28th of June is not all of June.  My reading of MODIS images is that the early part of June 2012 was much sunnier with lots more surface melting than we've seen this year, and then around the 21s a low pressure system moved in causing cloudy conditions in 2012 for much of your analysis period - and by the time the cloud cleared at the end of June a significantly dispersed pack was revealed and sunnier conditions early in July did a lot of damage on this weakened pack. 

23
Arctic sea ice / Re: The 2018 melting season
« on: June 29, 2018, 03:04:35 AM »
I know that it is overwhelmingly likely that you are correct, Michael, but I have a novice's question to ask.  If the Arctic ice is fresh, then its melting point is 0 C, I presume.  If the ocean water below is saltwater, then it can be up to -1.8 C, which means that it is then colder than the melting point of freshwater ice.  So in this simplistic formulation, the ice should not melt -- it should even form during these conditions at the bottom of the ice, even without a lot of heat being sucked way at the interface between the ice and the atmosphere.  Now, I suspect that salinity/entropy has got something to say here, but what exact physical principle is at work?  Is it ultimately entropy -- that the salt ions and water molecules will tend to become as mixed as possible?  And/or is it that the ice has a lot harder time growing when salt ions are present?  Or... (I often discover something I never thought of...)   


I hadn't thought about that angle.  The salty water below would not freeze and neither would the ice melt.  It is the multi-year ice that is fresh and the first year ice is much saltier, and there is a good amount of first year ice north of 80N. 

Looking through some MODIS images, channel 3-6-7 shows quite a lot of red in the high Arctic at the end of June in 2007,2008, 2010, 2011, 2012, so some substantial surface melt.

Current conditions - its almost a tale of two Arctics.  The Pacific side has some significant ice dispersal deep in the Beaufort, and plenty of red suggesting surface melt.  From Greenland towards Laptev there is quite an area of solid looking ice that is still supporting a crack/lead pattern instead of separating out into individual floes, and little reddening/surface melt.  I'd say the Pacific side is well on the way to a major meltout, and the Atlantic side will hold up quite well, suggesting that an extreme outcome in either direction is less likely than normal this year.

24
Arctic sea ice / Re: The 2018 melting season
« on: June 29, 2018, 12:39:22 AM »
I'm a bit late to the friv bashing session.  But I'll add that if the ice isn't freezing, it is melting.  The ocean below is always warm enough to melt the ice, and freezing only happens when the air above is far enough below 0 to more than balance out the slow addition of energy from below.  I would say that there is never any freezing happening in June, and that the ice north of 80N is basically always melting in June, but that the melting except possibly in rare circumstances (and near the Atlantic edge around Svalbaard) is too small to matter.

25
Arctic sea ice / Re: The 2018 melting season
« on: June 08, 2018, 02:55:43 AM »
Should the current cyclone be compared to the GAC?  Or to cyclones that occur in the north Atlantic or north Pacific.  Cyclones outside the arctic can get a lot stronger than the GAC, for instance Bering Sea cyclone at 943hp, with a note that cyclones reach below 930hp one or twice a year.  Or an Atlantic Cyclone that managed to reach 914 hp.

Impacts?

Will make a mess of the Atlantic front, but much of this is doomed ice anyway.  Perhaps it will accelerate warm water from the Atlantic into the Arctic, but I don't have a good handle on that current.  Lots of upwelling on the Atlantic/Arctic boundary.  Will that warm or cool the surface?  Upwelling = warming in the Arctic proper, but cooling in most of the Atlantic.  Where is the boundary between these two opposing trends?  Longer term the cyclone seems to hang around as a weaker system and looks to me like it will help to cool things down in the central/Canadian parts of the Arctic.

More concern to me is moderate high pressure ridge setting up in the Pacific sector, and the strong import of warm air between the ridge and this low.  I see strong sunshine and surface melting kicking off from Laptev to Chukchi/Beaufort.

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