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Messages - Kethern

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Arctic sea ice / Re: Latest PIOMAS update (March)
« on: March 03, 2017, 05:54:20 PM »
From day 59 to maximum volume the average gain is 2.103 x  1000km3

Attached is the chart for Max Volume - Volume at day 59.

Average volume gain from day 59 to max is 2.103.
Maximum Volume gained from day 59 to max is 2.707 in 1985
Minimum Volume gained from day 59 to max is 1.266 in 1990

Second graph is that of Max Volume - Min Volume.

The average volume loss is 16.907.
The Max volume loss was 19.693 in 2010
The Min volume loss was 13.925 in 1996

So from those numbers:

If we have a perfectly average year we end up with a minimum of 3.805 x 1000 km3. And 2012 keeps its record by a hair.

Best case (maximum gain, minimum loss) ends with a minimum of 7.391, ok I think we all agree that is unlikely.

Worst Case (minimum gain, maximum loss) ends at 0.182  :o

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Arctic sea ice / Re: The 2016 melting season
« on: September 08, 2016, 03:27:11 PM »
Thank you! That helps a lot. Remember everybody,  that is a giant section of reserve(sanctuary) 
MYI going down.
The Bastion has fallen.

Larger view of the region to put it all in context.  Total area in view is probably about 800,000KM2.

[Edit:  The only thing saving it right now is the weather has wind pushing in from the SSE over most of the next week.  If another polar low sets up, it will be on its way out.]

You mean like this:

(Note long range weather forecasts have been known to cause undue stress and/or disappointment.  Take dose of salt as needed to prevent anxiety or excessive enthusiasm.)

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Arctic sea ice / Re: The 2016 melting season
« on: September 07, 2016, 09:09:13 PM »
As I pointed out in an earlier comment. If you look at it on polarview you can see a shear developing and its as if the East most mass of it is being pulled south and bent around the NE corner of Greenland. It is just a matter of how long it takes to move far enough south to melt.

Or more visually.

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Arctic sea ice / Re: Navy mil actic sea ice
« on: August 02, 2016, 07:37:40 PM »
I was just looking at the snapshot archives and there it looks like the last model run was on July 29th so there is probably a bigger problem going on than just access.

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Arctic sea ice / Re: The 2016 melting season
« on: August 02, 2016, 07:35:02 PM »
It is working fine with this link

Bear in mind that the model underlying ACNFS is admittedly not "working fine" at present:

http://forum.arctic-sea-ice.net/index.php/topic,1602.msg84108.html#msg84108

Regardless of any model problems, the snapshot archives are showing that the last run was on July 29th so there would appear to be some issue with the website or underlying software as well.

6
Arctic sea ice / Re: The 2015/2016 freezing season
« on: October 14, 2015, 07:22:56 PM »
There was some discussion on Neven's latest post on the blog about the ACE index - Accumulated Cyclone Energy - being the lowest in years.

I'm wondering what this implies about changes in circulation.

Low ACE implies that somehow, less energy is/will be transferred between lower and higher latitudes.

One take away (which was suggested) is that this implies lower levels of exchange between the tropics and arctic latitudes, by way of which, could cause (short term, most likely) levels of cooling in the high mid-latitudes sufficient it could lead to an increase in both land and ocean ice.

If what I posited about low ACE above is correct, then that is a possible outcome.

BUT, I'm not sure the low ACE actually reflects that.  IN fact, I'm not sure *what* ACE may actually be representing these days.

In a regime that existed previously - with high levels of ice coverage and lower arctic temperatures - I'd tend to agree that a low ACE could represent a problem.  But I think the overall state change in the Arctic - temperatures consistently 5-15C above the average baseline - may be what is artificially lowering the index.   In this situation I think we could still be seeing significant movement of heat into the Arctic - as evidenced by seaicesailor's last post - even with reduced cyclonic activity.

Or, perhaps the nature of circulation is changing so dramatically that ACE has ceased to be a meaningful measurement, or perhaps is now reflective of something completely different.

It doesn't *yet* seem to suggest less heat transfer into the Arctic.

I will have to see if I can get this to post on the blog (past efforts have been less then successful) but I think that the problem is not a low ACE but a bad data set at Weather Underground.

If you check the individual tabs, while the Atlantic and East Pacific go up to 2015, the West Pacific, Indian Ocean and Southern Hemisphere stop in 2011.  Assuming the global number is the sum of all then the last three years are going to be reported as artificially low.

Meanwhile at WeatherBell Models http://models.weatherbell.com/tropical.php they are showing this year with a total ACE of 771 which is 138% of the 1981-2010 baseline.

Given the number of strong storms in the Western Pacific this year I find that to be much more believable.

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Arctic sea ice / Re: Is the Arctic being geoengineered (in secret)?
« on: December 31, 2014, 06:26:17 PM »
I read somewhere recently that US meteorologists made a blunder with Hurricane Sandy, and that their deadly error was due to the storm being 'too weak' for an arbitrary limit of theirs, so that Sandy passed 'under the radar' for too long. Some sort of superstorm 'turf–war' between the state agencies....

Shortly before landfall Sandy went from being a hurricane to an extratropical storm.  The National Hurricane Center could not make forecasts for it at that point (literally, the software wouldn't allow it), so forecasting was handed over to the local National Weather Service offices.  That did not go smoothly. 

8
Arctic sea ice / Re: Stupid Questions :o
« on: July 16, 2014, 07:58:57 PM »
My understanding of J. Frances's theory about 'stuck' weather patterns is that it is a consequence of disproportionate warming of the Arctic, including the ever greater melting of sea ice. But wouldn't that only explain north hemisphere phenomena?

But aren't stuck patterns now becoming more common also in the southern hemisphere (for example, what NZ is experiencing now)?

Is the warming of the southern oceans enough to create a similar dynamic there as in the north?

Or is there something else affecting the movement of these systems?

(This is where the really stupid question part comes in...so be nice :-*)

Another thing we know about the basic changes going on in the atmosphere is that there is more water vapor (up by about 6% on average, iirc). Even though there is also more energy in the system, would all that extra water tend to slow down these system--are they just too heavy to move along as fast as they used to?

My first guess would be that it doesn't. The molecular weight of dry air is ~29, the molecular weight of water is 18. Assuming the water vapor displaces an equal amount of dry air than the extra water should be making the atmosphere lighter not heavier. Given the relatively small percentage of water to vapor to the total atmosphere I doubt it has any appreciable effect.

9
Greenland and Arctic Circle / Re: Greenland 2014 Melt Season
« on: July 03, 2014, 02:18:30 PM »
So what will the effects of a post tropical storm be on melting?



Especially with some of the SST anomalies he is going to pass over on the way there.


10
Consequences / Re: The Hazards of Public Awareness
« on: April 03, 2014, 10:25:30 PM »
because authorities delay notification to prevent panic . There are other reasons but those are the majority. What most people (and almost all of the media) think is panic is people reacting to the information they have, but if that information is wrong their reactions will be also.

That's actually a very good note, about the delaying of notification to prevent panic - which I suppose in a way is exactly what has happened with respect to climate change in the modern context.

Apart from the fact my analogy seems a little potentially weak from what you're saying, I'm a little curious - if you have delayed notification to prevent panic - and the information (the fire) is discovered without clear guidance as to how to respond, does the analogy still work, or do I need to try to find a better one?

I mean - in the context of climate change - it would seem to me that the fire is too advanced for everyone to survive, and spreading too fast to have a good chance to organise so late in the day. Although theoretically productive responses are still possible they require collective sacrifice and behaviour that doesn't seem to me to fall within the usual domain of human behaviour.

Based on the evidence, unfortunately too often bodies, no there is still not mass panic. People try to help each other, they try to take reasonable actions to escape. Sometimes the information is still bad, poorly marked exits or the people at the back of a pack not realizing there are problems at the front leading to crushing. Now some individuals will panic before others but generally it happens at the last "oh shit I am going to burn to death" minute. And to be honest most people are overcome by smoke inhalation long before they reach that point.

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Consequences / Re: The Hazards of Public Awareness
« on: April 01, 2014, 03:08:45 AM »

Instead I think I can come up with another analogy - a fire suddenly breaks out in the middle of a crowded theatre. What happens next?

I would venture to suggest that human nature predicts that in the vast majority of instances pandemonium ensues, as people lawlessly fight to try to get to the fire exits to escape (with the net result that far fewer people make it out of the theatre alive than if they had organised in a selfless and disciplined manner to evacuate as efficiently as possible).

As a member of the fire service and a fire trainer I have to say that this is mostly a media myth. People are killed at these types of incidents because the exits are inadequate (or locked), the fire spreads so fast that there is no escape or because authorities delay notification to prevent panic . There are other reasons but those are the majority. What most people (and almost all of the media) think is panic is people reacting to the information they have, but if that information is wrong their reactions will be also.

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