Sunday, 16 July 2017

The Arctic sea ice melt- update - 07/15/2017


Arctic sea ice - 07/15/2017

If I had to qualify the situation in the Arctic I would have to divide opinions between those who see the melt as being less than expected because of snow and cooler conditions in the Arctic and those who see a rapid melt, first and foremost because of the thinness of the ice and the spread of extent, giving a greater area for melting to occur.

As far as a Blue Sea event? Looks less likely but bets are on.



We just had 500,000 sq/km loss of sea ice extent in three days! It's very rare to have 200 k+ losses in one day from here on out, but Im thinking we might not only see a half dozen of those, but also a few 300 k's- thrown in! Extent may go up at times.... Even today a storm is pushing ice into these hotspots, but temporary increases only actually serve to spread out the ice and help it melt faster! 

Unbelievable heat just flowing in from Scandinavia and Russia for a few days.... 

Ice does not look healthy and if it was thin, nows the time it will start to show!!!


---Chris Eldridge, via Facebook


This North Greenland ice shelf will probably calve soon, too.

ocean.dmi.dk/arctic/nord.uk.php



Daily volume: 6,515 km³ (3rd lowest for the date) Δ –229/day
1225/week, –12140/month, +2923/year, –2627/5year (–29%)
Daily extent: 7,795,132 km² (4th lowest for the date) Δ –131k/day
645k/week, –2433k/month, +184k/year, +118k/5year (+1.5%)

2017 volume maximum 22,255 km³ on May 12th (*lowest*)
2017 volume minimum¹ 5,790 km³ on July 8th
2017 extent maximum 13,878,287 km² on March 6th (*lowest*)
2017 extent minimum¹ 7,795,132 km² on July 14th

¹Preliminary max/min

Source: JAXA for July 14th 2017.







Sea ice breakup and marine melt of a retreating tidewater outlet glacier in northeast Greenland (81°N)


Abstract

Rising temperatures in the Arctic cause accelerated mass loss from the Greenland Ice Sheet and reduced sea ice cover. Tidewater outlet glaciers represent direct connections between glaciers and the ocean where melt rates at the ice-ocean interface are influenced by ocean temperature and circulation. 

However, few measurements exist near outlet glaciers from the northern coast towards the Arctic Ocean that has remained nearly permanently ice covered. 

Here we present hydrographic measurements along the terminus of a major retreating tidewater outlet glacier from Flade Isblink Ice Cap. We show that the region is characterized by a relatively large change of the seasonal freshwater content, corresponding to ~2 m of freshwater, and that solar heating during the short open water period results in surface layer temperatures above 1 °C. 

Observations of temperature and salinity supported that the outlet glacier is a floating ice shelf with near-glacial subsurface temperatures at the freezing point. Melting from the surface layer significantly influenced the ice foot morphology of the glacier terminuиs. 

Hence, melting of the tidewater outlet glacier was found to be critically dependent on the retreat of sea ice adjacent to the terminus and the duration of open water.




Current DMI and NOAA SST anomaly charts. They are different in specifics but the general theme is the same - a lot of warmer water all around, especially on the Pacific side. NOAA's version has been getting particularly angry looking recently.

Still a few more weeks of serious insulation to crank those temps higher, and the remaining ice will be surrounded by a killing field,( as well as storm driver and source of anomalous snowfalls later on)

As a note, at some point the link between NH snow extent and ice pack extent must be severed if a warmer Arctic continues driving anomalously high snowfalls in Siberia and Canada. 

At some point there will be ice- free ocean but still a lot of snow on and

2016


2017


The first attachment is from July 10 to July 14 of 2016. The second attachment the same dates but for 2017. They are both Nullschool Temp at 850 hPa. It looks warmer in 2016.


The first attachment is from July 10 to July 14 of 2016. The second attachment the same dates but for 2017. They are both Nullschool Temp at 850 hPa. It looks warmer in 2016. 

Perhaps it was warmer in 2016. That could be more incoming heat, or the cooling effect of melting ice this year. IMHO theres not a big difference climatically between 2016 and this year. but the preconditioning  of last year prevented a lot of heat loss from the ocean over winter and left us with a slush pack that is an efficient cooler and condenser in the global atmospheric circulation system at the expense of basin wide exposure rather than mostly just the periphery exposed to melting with weather system exclusion resulting as our past experience is limited to .

Heres the Jet stream at 250hpa comparison between 2016 and 2017.


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