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1
Arctic sea ice / Re: The 2020 melting season
« on: July 29, 2020, 06:50:35 AM »
For what's it's worth, HYCOM shows an interesting forecast for north of Greenland in early August - a large gap opening up, larger than anything I've seen there before.

Bear in mind, though, HYCOM does tend to be a bit enthusiastic at times. It remains to be seen whether its forecast comes off!

Source: https://www7320.nrlssc.navy.mil/GLBhycomcice1-12/navo/arcticictn_nowcast_anim30d.gif

2
Arctic sea ice / Re: The 2019 melting season
« on: August 11, 2019, 07:05:32 PM »
Interesting to see gaps in the ice showing up in worldview as far north as 89N. The attached link is to an area of cloud free ice from 150W to 150E (due north from Barrow to the ESS/Laptev border) and from about 88-89N (100-200km from the pole.)
It's in a terrible state all the way to the Pole. Yesterday's imagery shows it well, no fancy channel-fiddling needed!

https://worldview.earthdata.nasa.gov/?v=-306950.4643315668,-193208.65791401532,348409.5356684332,146247.34208598468&p=arctic&t=2019-08-10-T16%3A00%3A00Z&l=VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor,Reference_Labels(hidden),Reference_Features(hidden),Coastlines

3
Arctic sea ice / Re: The 2019 melting season
« on: July 29, 2019, 06:21:35 PM »
Time for another HYCOM thickness comparison - first today's chart, then the same date in 2016. The 2012 chart uses a different algorithm and isn't included here.

Of note is the way that the area adjacent to the north of Ellesmere has gone from having thick ice in 2016 to a thin area of no ice in 2019...

(The lack of ice north of Ellesmere shows up well on yesterday's EOSDIS, too - attached to this post).




4
Arctic sea ice / Re: The 2019 melting season
« on: July 16, 2019, 07:25:35 PM »
A few pictures from HYCOM (which is absolutely fine to use btw, if you have errors import the cert to your root store and you won't see any more messages).

1 - today's HYCOM
2 - the same day in 2016
3 - HYCOM at the 2016 minimum

(A different algorithm is used compared to 2012, so I've not posted those charts here).


5
Arctic sea ice / Re: The 2019 melting season
« on: July 03, 2019, 08:39:33 AM »
Let's not refer to HYCOM too much. I can't even access the NRL site anymore without getting repeated warnings from my virus scanner. Who knows what they're doing over there.
The warning will be because their SSL certificate is issued by someone not in your root store - i.e. the Department of Defense. It's all above-board and nothing to worry about (and I say that as an IT nerd).

Here's the archive sea ice thickness chart from the same stage in 2012 - the difference to the current forecast is stark!

(EDIT: I've attached the minimum chart from later in 2012 for comparison. I suspect their algorithms will have changed since then, but I find it an interesting sight as even at the minimum the HYCOM thicknesses were greater than we have now, in July!)


6
Arctic sea ice / Re: The 2019 melting season
« on: July 02, 2019, 05:36:23 AM »
I've included a couple of archived Bremen concentration maps (earliest I could get for July was the 23rd), and as you can see, 2012 and 2016 don't appear definitively "holier" than 2019; at least from what I can tell. (edit - though 2019 has a lot more purely open water.)
Here's the Bremen map for the 3rd July 2012.

7
Arctic sea ice / Re: The 2019 melting season
« on: June 29, 2019, 05:35:03 PM »
The latest HYCOM forecast is sobering - the North Pole is looking increasingly vulnerable, with a massive loss of thickness across the basin.

https://www7320.nrlssc.navy.mil/GLBhycomcice1-12/navo/arcticictn_nowcast_anim30d.gif

I've attached the final frame (forecast for a week's time) to this post.


8
Arctic sea ice / Re: The 2019 melting season
« on: June 18, 2019, 06:27:48 PM »
Looks like it's about to kick off in the Laptev...

Yesterday's image vs today's, showing the fast ice crumbling. (Click to animate)


9
Arctic sea ice / Re: The 2019 melting season
« on: June 16, 2019, 12:40:44 PM »
University of Bremen link https://seaice.uni-bremen.de/sea-ice-concentration/ still not operational.

In dire need of a pretty picture of Jun 15 sea ice, I looked and found
https://seaice.uni-bremen.de/data/amsr2/today/Arctic_AMSR2_nic.png

works fine.
(It's the URL for the most recent map, so updates daily. The other links I posted in the data thread still work fine - static images are working via Bremen, just not the dynamic stuff.)

10
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 15, 2019, 06:27:02 PM »

Lucky ? - from there can't look at the other stuff?
You can look up other days' charts by tinkering with the URL below:

https://seaice.uni-bremen.de/data/amsr2/asi_daygrid_swath/n6250/2019/jun/Arctic/asi-AMSR2-n6250-20190613-v5.4_nic.png

(Note that for other months you'll need to change the /jun/ bit as well as the date in the filename).

If you know exactly what you're after, you can browse the files here:

https://seaice.uni-bremen.de/data/

Looks like it's just the homepage which is down, the actual files are fine.

12
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 15, 2019, 05:47:29 PM »
My prediction, then, based on observation, climatology, and history: 2019 is about to see a very large--perhaps even record-breaking--drop in ASI extent.
That sounds like a sensible prediction to me!

I would agree with those who've posted to say that it's the melt ponds confusing the sensors and that we're primed for a swift break-up of the Laptev fast ice; it seems that we've gone through what usually takes a couple of weeks in less than a week.

This GIF of part of Laptev shows it well... we go from fast ice, to "blue" fast ice awash with surface melt (which appeared as water in Bremen charts, for example), to a whiteish drained ice state (which appears as ice again to the sensors).

However, I would imagine that drained ice isn't going to hang around much, it reminds me of a slush puppy after you've sucked out all the flavouring, leaving just clear slush behind!

(The GIF runs from the 7th to the 14th June, a frame a day).

13
Arctic sea ice / Re: The 2019 melting season
« on: June 11, 2019, 07:52:55 PM »
The 12z GFS has really gone off on one at the day 10 mark - showing mid 30s temperatures (celcius, that is!) adjacent to what presently is fast ice on the shores of the Laptev.

https://pamola.um.maine.edu/wx_frames/gfs/arc-lea/t2/2019-06-11-12z/80.png

(or via https://climatereanalyzer.org/wx/fcst/#gfs.arc-lea.t2 if that direct link above doesn't work - choose the 12z run of the 11th June).

I'd take that the same way as I would any forecast at 10 days, i.e. with a massive pile of salt, but nonetheless it's quite amazing to see. I can't imagine any ice lasting for long with that sort of heat blowing over it...


14
Arctic sea ice / Re: The 2019 melting season
« on: May 29, 2019, 05:16:38 AM »
current temps in barrows alaska 12C

More like 2C.

https://w1.weather.gov/obhistory/PABR.html

(That's the airport, which is on the south side of the town).

That said, the dewpoint is now above zero (Celcius) and that'll be accellerating the melt.

15
Arctic sea ice / Re: The 2018 melting season
« on: June 16, 2018, 08:31:15 AM »
Watch that fast ice crumble! This is three days' worth of imagery of the Laptev Sea, 14, 15 and 16th June.

(Click image to see animation).

16
Arctic sea ice / Re: What the Buoys are telling
« on: August 22, 2017, 04:11:32 PM »
Any ideas as to what that big iceberg-looking thing is?

http://obuoy.datatransport.org/monitor#buoy14/camera

(Attached a screengrab for when that image changes)

17
Arctic sea ice / Re: The 2017 melting season
« on: August 02, 2017, 05:22:03 AM »
7-31 to 8-1 on UBremen must have easily been 200K if not 300K KM2 area. WOW. The day over day difference is enormous and in the Beaufort a massive chunk of extent simply vanished!
It's an impressive loss, that's for sure! (GIF below shows 31st July / 1st August images)


18
Arctic sea ice / Re: The 2017 melting season
« on: July 22, 2017, 06:31:29 PM »
A view of the waves currently breaking on the shore at Utqiaġvik (Barrow as was):
And with a strong westerly breeze with a fetch of hundreds of miles, the waves are set to increase for the next few hours, peaking at more than double their current height! If that forecast comes off the view will be a bit different this time tomorrow...

http://www.tides4fishing.com/us/far-north-alaska/point-barrow

I doubt the swell will be doing the ice much good as it heads eastwards.

http://polar.ncep.noaa.gov/waves/viewer.shtml?-multi_1-latest-hs-alaska-


19
Arctic sea ice / Re: The 2017 melting season
« on: July 08, 2017, 05:48:34 PM »
Looks like some pretty big action going on off the coast of Siberia - this is a comparison of the 7th and 8th July, via Worldview.


20
Arctic sea ice / Re: The 2017 melting season
« on: July 08, 2017, 04:15:33 PM »
Edit. Just noted from the animation that the "istmus" of ice attached to Alaska has been shrinking extremely fast these last three days. I attach a detail using Uni Hamburg AMSR2 maps this time
Utqiagvik (Barrow) has been reporting some very moist, very mild air of late - all blown in by southerly or SW'ly winds. A dewpoint of 8-11C will zap ice at an alarming rate, so it's no surprise to see that "isthmus" shrinking so quickly.

http://w1.weather.gov/obhistory/PABR.html


21
Arctic sea ice / Re: The 2017 melting season
« on: May 31, 2017, 06:28:51 PM »
Looks like the crack has almost made it across the whole of the north of Greenland... the odds on it reaching the Atlantic side in the next day or two must be short!


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