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Before we get too deep into melting season, would some of the more seasoned posters mind giving a handful of things they will be keeping an eye on over the next few months to judge how 'good' or 'bad' the melt is going?
5 fingers worth to start with? Not necessarily in order of time or importance!
1. How soon melt ponds and/or open water hang around in the Beaufort Sea this year. Things started very early last year:
Among other places, it looks like there is melting and thinning out of ice within parts of the CAA.With current temps there, I doubt we are seeing any thinning out in CAA. More like the usual thickening-in I'd say.
Most of ice of the Arctic proprr keeps thickening until June, regardless if later it melts precipitously or not. If the daily average temperature stays under -2C, sufficiently far from the edges, the ice layer keeps growing at the bottom, and even when it goes above freezing it takes a while (some days) for the heat to reach the bottom and this stop growing. Something Jim Hunt shows in the forum neatly every year with the buoy data.Hasn't ever not been April for highest month on record.
There has never been better conditions for a March highest average month.
Remember we are talking highest monthly average, meaning you are also betting on a significant amount of ice sticking around until MAY.
The 1979-2016 average monthly increase from February to April is 3.058 k km3, so adding 17,400 we have a total of 20,458 km3.+1
I choose the 20.25-20.75 km3 range.
You must be a god if you want to abandon the thermodynamic equillibria assumptions and try solve the underlying discrete quantum equations with 10^26 or more degrees of freedom... to end up getting similar results because the thermodynamics models have been working really well for centuries.Let me phrase my stupid question a slightly different way. What evidence do we have that we are using the right kind of mathematics for predicting what will happen in a discrete discontinuous system over a long period of time? (Long being over about a month.)Kinda rhetorical, Jim, but we don't. What we have is the output of the models themselves.
I really don't think the reduction of skill with time is a result of the math. I think it is a result of the inputs, their granularity, and our understanding of the system mechanics.
I'll agree that right now the major error is our lack of data on the initial conditions, with lack of understanding of the mechanics coming in a close second, but it still seems to me that using a math which models temperature as a continuous "Real" variable rather than as billions of discrete changes will simply never be able to make accurate long range predictions. Discrete Topology simply isn't the same math as continuous vector fields. In particular, the group of Integers has all sorts of funky subgroups and other properties that only show up with very large numbers.
My stupid question of the day: Are there any climate models out there that use system dynamics rather than trying to model a natural system for any length of time by pretending it is a linear vector space and using arrays of differential equations?It is difficult to understand the question Jim, because I see both options you give as equivalent. An array of differential equations applied over a vectorial quantity ("linear"?) or several scalar and vectorial quantities, can be a mathematical model of a dynamical system, suitable for performing computations and developing predictions of the underlying dynamical system.
Btw, Neven, "sis" is usually a colloquialism for "sister". Although I'm sure seaicesailor wouldn't be offended by the monikor.LOL
I've been looking at ASCAT radar images and saw some interesting features. Here's an animation for the past week, and those features are in the first frame (white circle and rectangle):FYI and FYI according to the russian service that you point to in the ASIG, Neven. The elongated structure seems trapped FYI between the two surviving arms of ice in September, and the other region has been growing in extension as the surviving ice drifted northwards.
Usually, dark means thin in radar images, and these features have been there since November. The one in the circle looks especially interesting, but I don't know if it means these regions are thinner. And I haven't compared to other years yet either, but I thought I'd throw it out here to see what you guys think.
Anyway, so the topic doesn't derail again into awful nonsense, I am quoting Wipneus's thickness map updates, which have been lost in the crap:A lot of the thin FYI in Beaufort appeared in fact in 2016 during February so it was few-days-old ice. Product of ice drift opening up gaps along the coasts and refreezing immediately. Like Laptev sea this year.Here is the animation for February.This month I present the thickness maps for the last day of the month, instead of the mean monthly map. Should be more relevant.What I find quite interesting is that the first year ice in the Beaufort this year is actually thicker than it was last year. Has Beaufort been cooler this year?
Here the thickness map for 28 Feb 2017, comparison with previous years and differences with previous years.
Seaice: If Piomas is right about the location of most of the last thick ice, and if that drift forecast is correct, a large volume of ice is just about to get a good push towards the Fram exit.Yes, i agree, and ice melting near Svalbard and Greenland, probably why Feb volume anomaly stayed flat, regardless of the faster refreezing of late Feb. and the constant drift, refreezing and accumulation of ice at ESS.
Right, I commented along similar lines the other day but the thing about the snow is a double edged sword as most know here.In my humble opinion, there has not been appreciable ice moving compared to the same date last year. If it stays quiet until June, will be healthy. That's a big IF anyway.Thought people might find this interesting... Beaufort yesterday vs. this time last year (i.e. mid-crackopalypse)...Last year, there was actually something to *crack*, and other bits of it which were solid enough to resist.
Everything there is FYI, and most of it less than 1.7M; if it gets stressed, it breaks, and spreads out the force, rather than transmit it.
This is consistent with the observation that a predominantly low-dominated Arctic weakens the Gyre. Weakening of the Gyre stop positioning MYI in the Beaufort Sea and creates no ocean gaps far so easy. This might be considered as being a negative feedback due to a wetter and stormier Arctic (positive for ice rebound); other negative feedbacks of storminess could be later refreezing, greater accumulations of snow in winter and spring, and overcast skies in May and June.
Another lurker who has read this blog for years. This topic is dead. The melt has begun. The past 2 days have seen some serious ice disruption (satellite visual imagery). I have not yet checked the daily image posts, but likely some eye openers for everyone.
Might that high cause a cracking event (albeit not as big as the one in 2013)?It will be interesting to evolve toward the summer with similar FYI (although thinner) in the Pacific half of the Arctic as 2013 but a different weather.
I know, sorry if I sounded condescending.TT you put too much confidence in that product.I guess you mean the Wipneus chart derived from JAXA data. It comes into use. But I look at several products combined with common sense to make a conclusion...
TT you put too much confidence in that product.That gives a glimpse of the old CAB. All that export, and yet concentration and volume both are growing. I don't have any false hopes that it will last, but it's good for it to have at least one last hoorah for the season.
While I don't doubt volume should increase with the colder weather I find it hard to believe volume is greater than this time last year when FDDs this season are 20% lower than at the same time last year, at least above 80N. Could all the snow on t3he ice be fooling the instruments?
Using the reanalysis, we can calculate also the mean of the downward radiation flux...
So, what if we try with the precipitable water?
It looks way better...
I will not try an argument about chickens and eggs. It is of course difficult to disentangled all the mechanisms ongoing. But at least the increasing of water vapor, linked to warming of the temperatures but also to the decrease of Arctic sea ice, is increasing downward radiations.
The major point is that a warming of 20°C or 30°C is not impossible at surface is thus not impossible. With global warming, the "thin" -a 2 km thick and 20°C inversion is massive for an inversion in the absolute, but compared to the whole atmosphere this it is not so thick nor so cold- the "thin" layer of permanent inversion is set to be destroyed, with only marginal warming above. Usually there is around 5 to 10°C between surface and 850 hPa. Even a 7-8°C lapse rate with a 850 hPa layer around 250K would imply a mean surface temperature a bit below 260K, around -15°C, barely enough cold for sea ice.
This graph shows the warming of the Arctic layers :
The surface 1000 hPa is warming fast and is now warmer than the 850 hPa for the first time since 1981 (and probably since many millenniums...). And the strength of the inversion (or of the now non-inversion) taken as the difference between the 850 hPa and 1000 hPa temperatures :
I totally agree, the more images I see of it, the more I think this was an incredible event. Not sure if somebody remember such a mess being done of so much MYI in a handful of days!Another view of the debris left behind by the powerful storm that passed over Fram Strait a few days agoThe Fram situation is amazing and disturbing. What looked like good ice cover turned to an ice cube soup in a few days of battering, and this in February. Were it not for the MYI the whole thing could have become open water. I shudder to think what the summer might bring.
Feb 13-18, 115 hour loopThere is an interesting feature in this animation, sort of a Lake Ness monster showing the head in Beaufort sea. There is like a river of water/ice just flowing near the Barrow coasts. Says a lot about how the ice state is in this part of Chukchi/Beaufort seas, recently formed and thin, that an underlying current of warmer water may by breaking through and showing up... at least temporarily.
Pretty good flow south through the Bering Strait.
Imagery courtesy of the University of Alaska at Fairbanks
I05 band. Alaska at bottom center
I've been able to look some more into this, with the help of Michael, who sent me the data that allowed me to create this graph:Of all this, what amazes most is your eyeballing capabilities. Man, that you were able to detect this from the Cryosat maps with the colors they have ...
... All we know is that the slow 'drip ,drip' forcing through the 20th Century did away with all of that ice, ice big enough to build military bases ans radar station on!( the 'T' islands)....Nice that you point that out. In particular, Fletcher (T-3) Ice Island lasted from 1946 to 1983. It was a 14x8 km iceberg, with an estimated thickness of 50 to 60 m, and its stability allowed for harboring meteo stations, military base,...
There is a problem with the palette used in these maps, in that it is easier to distinguish ice from 2 to 4 m than from 0 to 2 m. Very difficult to compare the main extensions of ice which are under 2m !