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PhillipS

Greenland Melt Discussion

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Dr Jason Box is a leading researcher on the condition and dynamics of the Greenland Ice Sheet (GIS).  He has two blogs on the GIS, www.meltfactor.org, and www.darksnowproject.org, which is focused on his crowd-sourced research project on the causes and consequences of the GIS albedo changes observed in recent years.

 

Dr. Box had a recent post on Meltfactor that I thought might be of interest to the readers here.  It deals with possible effects on the AMOC of the large volume of freshwater discharge from the GIS.  An excerpt:

 

My contribution was my work of 6 years, a 172 year Greenland mass balance reconstruction published in a 3 part series in the Journal of Climate (Box and others 2013; Box, 2013; Box and Colgan, 2013), enabling Greenland melting to be brought more into context of its ocean thermohaline perturbation.

Rahmstorf_et_al_2015_NCC_Fig6.png
 
As an aside, the DarkSnow project is currently, April 2015, accepting donations for the 2015 research expedition.  I've supported it for the past three years and feel that they are doing cutting-edge research and finding out some surprising things.  It's worth checking out.

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Dr Jason Box is a leading researcher on the condition and dynamics of the Greenland Ice Sheet (GIS).  He has two blogs on the GIS, www.meltfactor.org, and www.darksnowproject.org, which is focused on his crowd-sourced research project on the causes and consequences of the GIS albedo changes observed in recent years.

 

Dr. Box had a recent post on Meltfactor that I thought might be of interest to the readers here.  It deals with possible effects on the AMOC of the large volume of freshwater discharge from the GIS.  An excerpt:

 

My contribution was my work of 6 years, a 172 year Greenland mass balance reconstruction published in a 3 part series in the Journal of Climate (Box and others 2013; Box, 2013; Box and Colgan, 2013), enabling Greenland melting to be brought more into context of its ocean thermohaline perturbation.

Rahmstorf_et_al_2015_NCC_Fig6.png
 
As an aside, the DarkSnow project is currently, April 2015, accepting donations for the 2015 research expedition.  I've supported it for the past three years and feel that they are doing cutting-edge research and finding out some surprising things.  It's worth checking out.

 

again another dataset that goes so far back way before reliable satellite measurements...mass balance in the 1800s really????

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again another dataset that goes so far back way before reliable satellite measurements...mass balance in the 1800s really????

 

Before you dismiss his findings you should read his papers to see whether you agree with his methodology - there are a number of proxies for glacial extent, such as terminal morraines and sediment cores.  Also, annual layer thickness in ice cores can give an indication of snow accumulation - at least for recent decades where compression hasn't obscured the annual record.

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Before you dismiss his findings you should read his papers to see whether you agree with his methodology - there are a number of proxies for glacial extent, such as terminal morraines and sediment cores.  Also, annual layer thickness in ice cores can give an indication of snow accumulation - at least for recent decades where compression hasn't obscured the annual record.

paywall....as usual. Not your fault. just annoying.

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paywall....as usual. Not your fault. just annoying.

 

I agree that paywalls are annoying.  But if you go to Google Scholar, search for Box Greenland Part, you will find non-paywalled versions of all three papers.

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I agree that paywalls are annoying.  But if you go to Google Scholar, search for Box Greenland Part, you will find non-paywalled versions of all three papers.

thanks.

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Before you dismiss his findings you should read his papers to see whether you agree with his methodology - there are a number of proxies for glacial extent, such as terminal morraines and sediment cores.  Also, annual layer thickness in ice cores can give an indication of snow accumulation - at least for recent decades where compression hasn't obscured the annual record.

 

I don't remember the thread, but Sokolov posted a nice description of how glacier movement and retreat can be understood through rock deposits.

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Surface mass has continued to run above the mean on this DMI graphic throughout the winter.  I don't know when the next GRACE update will be coming out tho.

accumulatedsmb.png

 

Here is 2013 for comparison.

Graph_Surface_Small_en.png

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This is just what happens when you have a +NAO.

 

I suppose we still haven't had enough warming to reach tipping points without a -NAO.

Yea natural variability is still dominant with an underline AGW component.

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I think it's been a quiet thread simply because the GIS melt season is just getting started.  So far it's been a mild melt season, at or a bit below the long-term average, for the Surface Mass Balance (SMB).  From NSIDC Greenland Ice Sheet Today:

 

greenland_melt_area_plot_tmb.png

And the Danish Meteorological Institute (DMI) hasn't started posting data for 2015 yet

 

Of course, SMB is only part of the GIS mass dynamics.  Mass loss through glacial melting and calving continues unabated.  Here is one recent news article that describes how glacial breakup in 2014 revealed a mountain on the coast of Greenland to actually be an island.  From the article:

 

20132014glacierconnection.jpg

 

According to glacier researcher Mauri Pelto of Nichols College, the retreat of these two glaciers from 1999 to 2014 has led to several new islands, one of which emerged just last year. In a blog post for the American Geophysical Union, a society representing earth scientists worldwide, the Steenstrup Glacier has retreated by 6.21 miles, or 10 kilometers, during the past 60 years.

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DMI has begun updating their PolarPortal website to show 2015 surface conditions. Here is the daily and accumulated Surface Mass Balance (SMB) plots:

 

SMB_curves_LA_EN_20150528.png

 

I found it interesting that over the winter Greenland had a lot more surface accumulation than 2012 did, but currently 2015 is starting the melt season from about the same point as 2012.

 

NSIDC is also showing the GIS as having a slow start to the melt season:

 

greenland_melt_area_plot_tmb.png

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DMI has begun updating their PolarPortal website to show 2015 surface conditions. Here is the daily and accumulated Surface Mass Balance (SMB) plots:

SMB_curves_LA_EN_20150528.png

I found it interesting that over the winter Greenland had a lot more surface accumulation than 2012 did, but currently 2015 is starting the melt season from about the same point as 2012.

NSIDC is also showing the GIS as having a slow start to the melt season:

greenland_melt_area_plot_tmb.png

It's not all that surprising that 2015 is starting off slower. We've had a +NAP signature for nearly the entire winter which keeps below anomalies over Greenland. PV camped over or near Greenland. Spring has been the same for the most part with the exception if a short-lived -NAO.

Forecast over the next 8-14 days more of the same with below anomalies over Greenland.

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DMI has begun updating their PolarPortal website to show 2015 surface conditions. Here is the daily and accumulated Surface Mass Balance (SMB) plots:

SMB_curves_LA_EN_20150528.png

I found it interesting that over the winter Greenland had a lot more surface accumulation than 2012 did, but currently 2015 is starting the melt season from about the same point as 2012.

NSIDC is also showing the GIS as having a slow start to the melt season:

greenland_melt_area_plot_tmb.png

It's not all that surprising that 2015 is starting off slower. We've had a +NAP signature for nearly the entire winter which keeps below anomalies over Greenland. PV camped over or near Greenland. Spring has been the same for the most part with the exception of a short-lived -NAO.

Forecast over the next 8-14 days more of the same with below anomalies over Greenland.

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Things are are about to

Change

I'm expecting it at some point, but NAEFS temp probabilities (which are excellent) showing more of the same June14-21:

hG25OJOh.png

But well see...

If this ridge develops being advertised by the Euro Ensembles then I agree:

3Np8I33.png

BTW...would've loved that blocking for winter....geez

Of course...if it's short-lived it won't be a big deal but if that becomes more prominent then the "heat is on". Right now some guidance has it short-lived while the Euro ensembles give a weak signal for it to continue in the long-range. GEFS ensembles giving mixed signals:

nao.sprd2.gif

To me it's a toss-up. I could easily see more blocking there as an atmospheric response to the developing Nino; however, aside from that the cold anomalies in the N. Atlantic are not friendly to long-term blocking.

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From the anomalies posted, the Euro shows the ridge setting up west of Greenland, which would keep northerly winds over Greenland itself thus cooler temperatures. The stronger warmth from that map would be Baffin Island, the CAA, etc...NAEFS keep Greenland chilly well into the latter part of June, anyway.

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After a slow start the GIS surface melting is picking up its pace.  From NSIDC:

 

greenland_melt_area_plot_tmb.png

 

greenland_melt_nomelt_tmb.png

 

The melting is increased by the albedo change of the GIS surface.  From the DMI:

 

Alb_SM_EN_20150604.png

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0z NAEFS Temp Probabilities keeping most of Greenland still in the greater chances of below normal anomalies June 21-28

 

2015061300_054@007_E1_global_I_NAEFS@TEM

All of the Arctic looks to be cold in the long range as the fractured PV returns to the Central Arctic Basin and pushes all the warm air away.

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Amazing we had the winter we did with a strong +NAO.

 

In any case, models show Greenland finally warming up as a ridge builds into the area. This is after a few more days of cold conditions with -10C 850s atop the ice sheet..A lot of cold continues to get dumped into the United Kingdom and Northern Europe where 850s are below 0C in many areas even in the middle of June, and this should accelerate with a significant trough moving into Spain/France as the NAO declines in the coming week.

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Let us know when "about to" turns to actually happening. Comical how certain posters ONLY show up when big melting is occurring, or when "something about to/in 7 days/ lets show hour 384 GFS to prove our point" is maybe going to occur LOL. Try a bit harder to hide your ridiculous bias man/women/ no actual education about said subject other than climate of gavin. 

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