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Messages - Viggy

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The forum / Re: Forum Decorum
« on: July 12, 2020, 07:32:10 PM »
I would ask that the new management team consider some sort of mission statement which reflects a commitment to scientific integrity. I would ask people to consider whether it is legitimate to be concerned about messaging that potentially dissuades people from hoping for a solution if such messaging is not grounded in science.
Every so often people start to want to mould the ASIF into a vehicle for themselves. Demanding a mission statement is often a prelude to a takeover bid.

Me? that's when I start to smell censorship - & that's when I start thinking about packing my bags and heading for the hills. The more different points of view on how all this mess is going to turn out the better. Don't try to fence me and the rest of us in.

(Bad behavior is a different story, as is being boring.)

The forum / Re: Forum Decorum
« on: July 12, 2020, 08:13:19 AM »
Every man has the right to an opinion but no man has a right to be wrong in his facts. Nor, above all, to persist in errors as to facts.
1946. Bernard Baruch

Arctic sea ice / Re: The 2020 melting season
« on: July 12, 2020, 07:03:41 AM »
Here are the area weighted & averaged 850MB temps from 65 to 90deg north during the period of May 1st thru June 30th plotted over the last 72 years. 2020 is first place and (to a lesser degree) is first for the month of June.

Via the interface screen grabbed below, you can plot all kinds of cool variables like precipitable water and geopotential height at:

Arctic sea ice / Re: September predictions challenge 2020
« on: July 11, 2020, 07:04:45 PM »
.. says an optimist . :) b.c.

Arctic sea ice / Re: The 2020 melting season
« on: July 07, 2020, 10:38:30 PM »
With regards to Judah Cohen's recent post, very high sea surface temperatures and ocean heat contents in the northern Indian ocean, Indonesian seas, and far western Pacific are causing excessive rains in eastern Asia and are stalling the progression of the Madden- Julian oscillation out of the Indian ocean - Indonesian sectors.  When the MJO gets stuck so can weather patterns in the rest of the northern hemisphere because the tropical convection that the MJO centers around is an enormous heat engine that is transferring heat from the overheated ocean to the upper atmosphere.

Global weather patterns are tied into the MJO phase. This is one reason the ridge-trough pattern over Asia has been stuck and that ties in with the ridging in the Arctic.

Note also that his point about intensifying temperature gradients between the ice and warming oceans apply both the Arctic ocean and the subarctic seas on the Atlantic side. The high over the pole has been coupled with the low in the Greenland sea. Greenland's ice cap is the cold side of an increasingly intense temperature gradient in the north Atlantic.

The map below shows a forecast  huge anomalous upwelling over the Indonesian region in August. The MJO will continue to be stuck according to the CFS model.

Greenland and Arctic Circle / Re: The Nares Strait thread
« on: July 04, 2020, 06:40:09 PM »
Kennedy. Huge holes. Much of the ice must have already gone south.

I'll do a GIF when DMI site finally updates.

Arctic sea ice / Re: 2019 sea ice area and extent data
« on: October 26, 2019, 03:10:45 AM »
So, as of a week ago, 2019 captured the last few JAXA daily records held by 2007, giving the 2010s a clean sweep. Interestingly, except for 2013 and 2014, the rebound years after 2012, every year of 2010s has some of the daily records. For now, 2016 has the most, but just about half those were after this date, so 2019 still has a chance of passing it.

Arctic sea ice / Re: The 2019 melting season
« on: July 12, 2019, 10:00:26 PM »
One more record to be registred.

The earliest date below 8M km2

The shortest ever "slot" from 9M down to 8M km2.

Old record was 7 days in 2005 !

EDIT: Source -

Arctic sea ice / Re: The 2019 melting season
« on: June 28, 2019, 02:27:32 AM »
But given the confusion the Slater map causes, I have to wonder why they publish it all.

The map actually does show probabilistic predictions, as stated on the website:

One way to think about the plot is that for the area that shows 80% probability of being ice covered on the forecast date, 20% of that area is expected to be ice free.

However, the model is purposefully simple. It is just a projection (for the same calendar date in recent years) of the average observed 50-day survival probability of ice at each concentration. It takes no account of regions, so it has reduced skill in regions that have peculiar melt patterns, where it may tend to err high (e.g. Hudson due to geography) or low (e.g. Greenland due to export). (By design, these regions tend to cancel each other out in the integrated prediction.) Just ignore such regions and the map is useful. One way to think of it as an interestingly-colored concentration map.

In fact, the predictions for the Hudson at this time of year are actually interesting. It illustrates just how greatly local conditions contribute to melt. It also gives an indication of how quickly other regions being "torched" might melt out. E.g. The Hudson will be mostly melted in 2-3 weeks, so unless conditions cool down along the Russian coast, one might likewise expect most of the yellows and oranges there to melt out in a similar period.

Finally, even if the map were not useful, "they" would not (and should not) take it down because, as it says on the website, it's not an official product, but a personal project of (the now late) Andrew Slater.

Arctic sea ice / Re: The 2019 melting season
« on: June 12, 2019, 03:22:47 AM »
Wipneus describes Fram volume export as near normal for the month based on piomas data.

In volume yes. But the ice around greenland is much thinner than in years past, thus more area exports due to the ice structure's fragility, and the volume ends up about the same.

Arctic sea ice / Re: The 2019 melting season
« on: June 04, 2019, 12:13:11 AM »
Pearscot, the heat content of the north Atlantic has built up slowly over the decades. It was quite low in the mid 1970s after the effects of "the Great Salinity Anomaly". In the late 1960s the Beaufort gyre dumped a load of fresh water on the Labrador sea and deep water formation slowed down. That likely led to a slow down of the Gulf Stream. Heat built up in the main development region for hurricanes and Camille reached cat 5 while New England had a cold and very snowy winters in the late 60s.

Anyway, the heat content of the north Atlantic has been increasing since the late 1970s and has slowly worked its way north into the subarctic seas. Heat has gradually moved from the subarctic seas to the Atlantic water layer at 300 to 600 or so meters in the Arctic ocean. That water has slowly upwelled along the continental shelves of the Arctic ocean adding to sea ice mass loss over the past few decades.

The fast way for ocean heat to have an impact on sea ice is by storms that track from both the Pacific and Atlantic into the Arctic.  Advection of heat and water vapor on the Pacific side of the Arctic has been very impressive the past few years and has led to the record low sea ice extents in the Bering sea region.

The SST anomaly animation has a lot of information relevant to atmospheric heat advection, but it's on a shorter time scale than the processes that have caused Atlantification of the European side of the Arctic ocean.

Arctic sea ice / Re: Albedo-Warming Potential
« on: April 07, 2019, 12:11:26 AM »
The new near-real-time Albedo-Warming Potential script is programmed. If it updates tomorrow as intended I post the website link. The regional data has to wait until I structure the regional data from the previous 40 years.

Arctic sea ice / Re: Are 3 dimensions better than 2?
« on: April 06, 2019, 11:33:10 PM »
As Wolfgang Pauli, Viggy, Jim Hunt and many others have observed: "Das ist nicht nur nicht richtig; es ist nicht einmal falsch!" 

See also: Gish Gallop

I finally learnt something in this thread!

Also, I think both the pro and con sides can agree that due to the nature of this thread, it will continue on circuitously till we have all burnt out far too much intellectual capital. There will be no agreement or conclusions here. Lets move on to more fruitful conversations.

Agreed.  We will never come to agreement on matters of opinion.

Arctic sea ice / Re: Are 3 dimensions better than 2?
« on: April 06, 2019, 09:27:19 PM »
As Wolfgang Pauli, Viggy, Jim Hunt and many others have observed: "Das ist nicht nur nicht richtig; es ist nicht einmal falsch!" 

See also: Gish Gallop

Arctic sea ice / Re: Are 3 dimensions better than 2?
« on: April 05, 2019, 11:09:01 PM »
Is it real world when all the volume numbers are models?

Models are not real. The observations feed into the models are though.
Models are estimates derived from the best available data, complete with confidence levels. Even if imprecise, as year over year the use the same inputs and rules, They can be used to identify trends and changes in scale.

Arctic sea ice / Re: Albedo-Warming Potential
« on: April 03, 2019, 01:45:58 AM »
Stumbled on to it while looking at your AMSR2 tab and I have to say it is absolutely beautiful in its presentation.

Please keep up the amazing work and cannot wait for the near real time data additions!

Thanks Viggy, it really means a lot to me. The presentation takes up about 75% of the time, but is also the most important part.

Arctic sea ice / Re: Albedo-Warming Potential
« on: April 03, 2019, 01:19:03 AM »
BAM! Two years have gone by without an update.

I finally have the processsing power and coding skills to take the AWP model to where I intended it to be. Instead of only calculating the anomaly of potentially absorbed solar radiation. I now calculate the raw accumulated values, the anomaly and a percentage of the current year to the maximum possible (complete Ice-free conditions). From the 1980s to 2010s this percentage has gone up from roughly 52% to 62%. Generally from August onwards the Arctic is 75% icefree and from September onwards the Arctic is 90% icefree.

Everything is now much better presented with interactive graphs and sliders to compare individual years. The regional data is already calculated, but needs even more work for proper presentation. Near-real time data for 2019 is in the works too.

Fancy new webpage:

Still too short documentation of AWP model:

Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: April 02, 2019, 10:27:49 AM »
Based on minimums 1979-2018 and linear regression, I calculated probabilities to get minimum below 2012 in 2019-2035 (blue dots). Also cumulative probability (red dots) and probability to get minimum below 2012 first time that year (green dots).

Arctic sea ice / Re: The 2018 melting season
« on: August 14, 2018, 03:13:14 AM »
Viggy's last image shows more land-fast ice breaking away . This now leaves the most Northerly point of land-fast ice exactly where it was on the 28th Feb this year .
 The flow I have been watching since lift off from tip on Aug.1st has travelled 110km in 12 days

My Worldview observations has me wonder at the low rate of melt being reported ... I feel this melting season is far from done .But then I thought it would start early when it immediately stalled :)
 ps .. I notice the Worldview mappers have an opportunity to redraw Ellesmere island's North coast more accurately as land fast ice ( and apparently large chunks of Ellesmere ) head North .. :)

I am fairly sure this winter is going to be completely absurd (i.e., extremely cold and snowy), at least for Eastern North America. The shift to cold continents / warm Arctic since 2012 is unmistakeable undeniable and only worsening.

I got curious about WACCy results so I created this gif, ERA-I temperature difference of 1979-2000 vs 2007-2017.  (click to animate)

Arctic sea ice / Re: 2018 sea ice area and extent data
« on: July 30, 2018, 04:06:58 AM »
This discussion would be excellent material for one of the threads on "when will the Arctic Ocean be ice-free?"  I'd gently suggest moving follow-up posts over there.  Thanks!

Again ...

This thread is for discussions of 2018 sea ice area and extent data

Please move discussions about the future of the ice, the consequences of an ice-free Arctic, paleoclimate, human evolution, and other topics elsewhere. 

Arctic sea ice / Re: The 2018 melting season
« on: June 18, 2018, 09:43:15 AM »

Arctic sea ice / Re: The 2018 melting season
« on: June 12, 2018, 11:49:19 AM »
I'm imagining that the amount of energy to reverse the Beaufort Gyre (even locally) and the amount of heat generated as a result of it, must be quite enormous?

I think that's a surface effect where the ice is being blown against the prevailing current. I doubt that the underlying current has changed much. So its easy to see how quickly that  increase in extent could reverse if the window blows with the current.

However pushing the ice through the water should cause some extra melt underwater which may have show up later, although we won't notice it.

Arctic sea ice / Re: The 2018 melting season
« on: June 08, 2018, 07:04:36 AM »
Rapid melt at the Gusinaya River delta in the East Siberian Sea.

Arctic sea ice / Re: The 2018 melting season
« on: June 07, 2018, 01:55:34 PM »
Yep latest GFS initializes at 959!

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