Early 2013 Melt in SE Greenland?

[RaenorShine]

I've been following the early season in Greenland on the new NSIDC site http://nsidc.org/greenland-today/ and have seen that there is early melt in the SW of Greenland over the past month or so.

However, according to Denmarks Meteorology Institute, the daily mass change in the ice sheet has been positive in this area for the past couple of days in the same area that NSIDC shows melting(http://www.dmi.dk/dmi/index/gronland/indlandsisens_massebalance.htm in danish).

Both sites use different measurements (NSIDC uses a satellite survey, DMI uses a model based on the weather to estimate mass change).

Looking at the weather in that area on Wunderground (http://www.wunderground.com/cgi-bin/findweather/getForecast?query=65.58000183,-37.15000153&sp=BGKK it looks to have been slightly above freezing during the day, and raining at times.

My question as a non scientist  (and a climate/ice newbie) is what is actually happening in the area?  I know that any ice melt and rain during the day will probably refreeze overnight at the moment, giving mass gain.

Also, could the rain be giving a false positive on the satellite survey (i.e. the rain leads to water on the surface of the ice, leading to a 'melt' reading)?

[Vaughn]

I made a comment about this in the "Black Carbon in Greenland Ice Cores" topic on this forum.  Considering that several temperature sources do not show temperatures below freezing or just slightly below, I am assuming that the actual melt in these areas does not amount to much.  What seems unusual it that the temperatures are this close to the freezing point to begin with. I am wondering what the ramifications for the beginning of the real melt season will be though .

[diablobanquisa]

Looking at the temperatures near sea level...

Tasiilaq: http://www.ogimet.com/cgi-bin/gsynres?ind=04360&ano=2013&mes=2&day=26&hora=6&min=0&ndays=30



Kulusuk Lufthavn: http://www.ogimet.com/cgi-bin/gsynres?ind=04361&ano=2013&mes=2&day=26&hora=6&min=0&ndays=30



Aputiteeq: http://www.ogimet.com/cgi-bin/gsynres?ind=04351&ano=2013&mes=2&day=26&hora=6&min=0&ndays=30


... I´m pretty sure that the melting in the ice sheet is an error in the satellite data (I don´t know the reason).

[Carex]

I, also not a qualified scientist, will throw out my view hoping that any errors will flush out real knowledge.  Melt does not require a change in mass balance.  It is a change of state.  It is not necessary for the liquid to run-off into a basin for melt to have occurred.  So, it is perfectly normal, in a cool light rain to have melt and an increase in mass. In most situations snow that has been melted and re-frozen is easier to melt again because of a lowered albedo of the new, altered form of the snow or ice.  Here, at 46 12' N latitude 85 45' west long., we are getting frequent melting but have had limited if any runoff of water to lakes and streams. 

Once the we get daylight for about 10 hours/day open south facing areas start melting, on sunny days, at about -5C air temp.  The surface temp in the sun is obviously higher.

[crandles]

Can direct solar radiation melt ice even when the temperature is below 0? Of course the water will freeze again whether it stays on surface or trickles down into ice sheet.

Pictures looks rather misty. Water in low clouds misinterpreted?

[Carex]

Air temperature is typically not recorded in direct sunshine so surface temperatures are typically higher than the air temperatures as officially measured.  (This dose not mean that the laws of physics are altered, only that standardized measurements can not measure everything). 

I'm not saying it was melting in Tasiilaq today, only that the satellite data seems reasonable and is not inconsistent with mass gain.  Weather Underground has Kulusuk reaching 0 C 10 times this month.  Rain and fog were each recorded twice. In Prins Christian Sund the forcast is near or above freezing through the weekend (couldn't get the months history). Warmer than here.

[TerryM]

Carex

This site provides Greenland weather history in an easy to use format.

http://www.ogimet.com/gsynop.phtml.en

Terry

[Vaughn]

It looks like some of the melting that NSIDC shows is at a higher altitude.  This makes sense.  Temperature inversions occur and it is much warmer at higher altitudes typically around 500meters to 1500 meters if the temperature inversion starts at sea level.  There was a couple weeks this January in western Oregon where we had a fairly extreme temperature inversion from about sea level up to about 500 meters.  The low level temperature was very stable at about -1 to -3 C.  The fog was quite dense and moderate snow fell at times although no areas received more than 3 or 4 cm of snow during that two week period. From 750 meters to  2000 meters (clear sunny daytime weather)the temperature was consistently above freezing even during the night.  The warmest temperatures were at about 750 meters elevation at +15 C.  Something similar to this could be happening at some of the places NSIDC is showing melt in Greenland especially if there is a warm southerly flow over the area from the Atlantic.  This type of flow could cause rain, freezing rain, or even snow at lower elevations where it would be/could be considerably colder.

[diablobanquisa]

In the "Cumulative melt days" product, NSIDC is showing in yellow the area near Aputiteeq (temperature data). Yellow means more than 40 days with melting: almost every day of 2013 from january 1st to february 26th.
The mean temperature in the first two months of 2013 at 925hPa (750 meters aproximately) above Tasiilaq or Aputiteeq is roughly between -7 and -10ºC.




This winter in Greenland is being warm, warmer than normal. But that continuous melting in the ice sheet  looks unbelievable to me.  I don´t know the reason, but I think NSIDC´s  product is having a sistematic error in that area.

[Apocalypse4Real]

Check out the article on this issue - of SE Greenland melt days from Jan to Feb 16, 2013.

http://blogs.discovermagazine.com/imageo/?p=291#.USOZhOghM2U

[RaenorShine]

Thanks all for your replies. 

Denmark's Meteorology Institute shows some mass loss yesterday in the area, but it looks as though there was very little snow around Greenland.  Their model only shows surface melt loss (not glacial). The 2012-3 overall mass gain looks to match the long term average.

Check out the article on this issue - of SE Greenland melt days from Jan to Feb 16, 2013.

http://blogs.discovermagazine.com/imageo/?p=291#.USOZhOghM2U

Thanks for finding some explanation from the NSDIC.  That is about how I read what was going on, a slight melt in the afternoons is showing as a 'melt' day. It won't make a material difference on the melt season as a whole but might be a harbinger of another large melt this year. 

What I find amazing is how persistent it has been during February (not just a couple of days here and there).  Temperatures have been well above average looking at a couple of the weather stations.  Is this another example of the Nothern Hemisphere weather getting stuck I wonder?

[diablobanquisa]

Wet snow in a short period during the day?
It seems reasonable.




20-30 days with wet snow in Tasiilaq/Kulusuk? (red arrow) This seems possible, since the maximum temperature has been above the freezing point in 24 days (at sea level) (link).

But... 30-40 days with wet snow in Aputiteeq (black arrow) (http://mapcarta.com/19194668)?
The maximum temperature has reached the freezing point only in 6 days...  (at sea level)  (link) 


And... are we talking about wet snow over the Ice Sheet or wet snow over ice-free areas?

I think the "melt days" (wet snow in any period during the day) near Tasiilaq seem to be real. But I don´t understand the 40 melt days near Aputiteeq... I continue thinking it must be an error.

About the significance of these days of wet snow, they point out that this winter is being very mild in southeastern Greenland.
Indeed, this winter is mild in whole Greenland (temperature anomalies at 1000 hPa during 2013 vs. 1981-2010 mean):




But it is not a unique event. The winter in 2010 was a lot worse for whole Greenland... (01/01/2013-02/25/2013 minus 01/01/2010-02/25/2010) (2013 is  milder only in the southeastern corner, and much colder over the rest of Greenland):




AO/NAO related?

500 hPa geopotential height climatology, january-february 1981-2010:


January-february 2010, 500hPa geopotential height:


January-february 2013, 500hPa geopotential height:



(in the historic data 1979-2007, NSIDC uses a different ice-sheet mask excluding some  southeastern coastal pixels that in 2013 are showing melting, difficulting the comparison with previous years. See Figure 3: http://nsidc.org/greenland-today/2013/02/greenland-melting-2012-in-review/ )

[TerryM]

A4R

That was an amazingly good article that you linked to, even the comments were to a large extent well thought out.

Diablo

All the stats I find for Aputiteeq show wind from the northern quadrant this month. I'd been looking for some rainy southerly winds as an explanation for the melt but don't find any.

I think it's still too early in the season to prognosticate, but softened, rounded snow crystals may lower the albedo enough to make a difference once the sun starts shining.

Terry

[Vaughn]

Thanks for all of the explanations and analyses on this topic .

[Artful Dodger]

Lot's of warm SSTs in the East Greenland Sea today:

http://www.sailwx.info/wxobs/watertemp.phtml?lat=70&lon=-30&radius=600

[Gary]

Hello everyone.

I am interested in what is happening in the arctic, but I have no knowledge or expertise to use to provide answers. I can only post questions.

So, today's question: Does anyone know if the early melting that is currently being seen in Greenland is also occurring elsewhere, for example in smaller glaciers and ice caps in Alaska, northern Canada, Scandinavia, Siberia, etc.?

My guess is that if it is warmer in Greenland, it may also be getting warmer in other places.

I am also guessing that these other smaller areas of ice will have completely melted away long before the last of the Greenland ice sheet melts.

I can't find a number for the total amount of ice in these areas, as a percentage of the amount of ice in the Greenland ice sheet. Any melting, however, will add to sea level rise.

Gary

[crandles]

The early melting doesn't necessarily mean less snow and ice. The water from melting for a brief period may well be freezing again.

I don't know if it is happening elsewhere.

http://climate.rutgers.edu/snowcover/chart_daily.php?ui_year=2013&ui_day=60&ui_set=2

only has anomalies at lower latitudes if that is any help.

Sea ice volume is likely to be increasing until May. Land snow will start declining earlier than that as land warms faster. But not this much earlier at those sorts of latitudes unless you go a long way south or have a nice warm ocean current flowing close by (edit: or at least lots of nearby open ocean).

[Artful Dodger]

I am interested in what is happening in the arctic, but I have no knowledge or expertise to use to provide answers. I can only post questions.

So, today's question: Does anyone know if the early melting that is currently being seen in Greenland

Hi Gary,

A good place to start reading, an following on a regular basis, is the U.S. National Snow & Ice Data Center (NSIDC) page called "Greenland Today":

http://nsidc.org/greenland-today/

Read some of the back stories, and subscribe to some of their other pages which are listed at the bottom of the page under the heading: "Stay Current".

Good luck Gary, and welcome to the Arctic!

[diablobanquisa]

Diablo

All the stats I find for Aputiteeq show wind from the northern quadrant this month. I'd been looking for some rainy southerly winds as an explanation for the melt but don't find any.

The pixels near Aputiteeq are spurious. Everyday showing melting, even this week,with a cold snap and the maximum temperature in the area below -10ºC

[Carex]

I agree, this does not look like melt.  What are other possible explanations? What could either add water to the surface or create a false "wet" data analysis consistently in the same spot?  An outlet of water from the ice cap interior, a glacial seep?  A normal ground water seep on a slope?  The local fish gut dump?  Yes, I'm reaching and hoping to flush out better ideas.

[Buddy]

Early melt STAGE II is starting.  Melting increased significantly yesterday, and temperatures are forecast to increase 10 - 15 degrees F over the coming week.

Narsarsuaq on the southern tip is forecast to see high temps of 43 - 46 degrees from this Friday through Monday.  The average high temperature for MAY is 46 degrees in Narsarsuaq.

As well....temperatures along the west coast are increasing....although still too cold to melt.

The SE coast of Greenland should see significant melt over the next 7 - 10 days.   

[RaenorShine]

I'd noticed that the melt has kicked off again after a couple of weeks of rest.

Looking at the weather over the SE of Greenland its around freezing, or just over with a lot of snow / sleet / rain, so mass balance is still positive on the Denmark Meteorological Institute Site, for that area. There have been some slight negative spots where there has not been any snow (as far as I can see).

As you say buddy, the weather forecast looks to see more melt soon, especially as the snow moves away and temperatures stay around freezing with sunny spells.

[Jim]

I've just noticed that the NSIDC Greenland melt site now shows no melting on their Melt Extent graph this year, and no areas of melt anywhere in Greenland - even the 'Cumulative Melt Days' graphic is blank.
Have they re-calibrated their data, or realised the previous readings were mistaken?
Does anyone know or have an inside track on this?

[Buddy]

I doubt it.  They are most likely updating it....although we shall see soon enough.

Over the next 5 days Narsarsauq on the southern tip of Greenland is forecast to have high temperature from 40 - 46 (F).  At Thule Air Base (750 miles NORTH of the Arctic Circle on the northwestern coast of Greenland) the high temperature is forecast to be 25 - 32 degrees (F) on Sunday through Tuesday.  The average high this time of year is ZERO (F) at Thule.  THAT is a pretty significant difference.  Parts of western Greenland have shown some of the highest amounts of warming over the last 10 years worldwide (I'll look for the link...but don't have it now).

We should see some increased melting over coming days....especially for this early in the year. 

[Buddy]

Here's the link that I mentioned above:  http://climatechangegraphs.blogspot.com/2012/08/arctic-sea-ice-volume-extent-charts_30.html

A study showed that parts of western Greenland have warmed more than 10 degrees (Celsius) over the past 20 years.  THAT...is a lot.

[RaenorShine]

I'm not sure what is happening on the NSIDC site either, it does look to me like a re-calibration though, as its not an entirely blank map. (look on the hi res image for a couple of light blue pixels).

The south west coast of Greenland is showing temperatures of up to 9C this morning on Wunderground so it looks like there should be some melt.

On the SE side, the webcams for  Kulusuk have an archive of daily pictures, you can see melt occurring at sea level (and more snow added!) by comparing the pictures. http://www.wunderground.com/webcams/alfis/1/show.html 

[Jim]

Hi RaenorShine,
It does look a bit like a re-cal, as the graph also has the teeniest little blips on it - but nothing like the data present up to just a few days ago.
New algorithms, data processing methods?

[Buddy]

High temperature so far this am in Narsarsuaq on southern coast is 52 degrees F (Sunday morning 10:45 EST).  Average high for this date in Narsarsuaq is 30.  Next couple days expected to be in low 40's.  Upernavik on west coast is in high 30's.

Melt continues....will be interesting to see Greenland melt maps when they are eventually updated.

[Buddy]

Monday morning (03/18) at 7:30 am at Thule Air Base on Northwest coast of Greenland (750 miles above Arctic Circle):  Temperature is 42 degrees F (42 degrees above the normal high temp).

Needless to say....melting has now started on western coast of Greenland over the past 2 days. I checked two different sources because I really didn't believe the temperature at first.

[OldLeatherneck]

With these extremely high temperatures across western Greenland, I would imagine that a gret deal of the new snow has melted at the lower elevations.  This will reduce the albedo very early into the melt season.  I'll be interested to see the next charts of the albedo in Greenland when Jason Box publishes them.

[Buddy]

There is also a fairly large area of ocean water about 400 miles south of Greenland that has been moving north over the past week.  The high anomaly of the water is quite high.....and it has been migrating north every day.  This will NOT be good for the melt season if it continues to both (a) intensify, and (b) continue moving north.  BOTH of which have been happening over the last week.

You can see it on this NOAA anomaly map at about "5 o'clock" on the map (it is off of Newfoundland right now);

http://climatechangegraphs.blogspot.com/2013/02/sea-surface-temperature-anomaly-weekly.html

It is a fairly broad area....and continues to intensify and move northward.

[Carex]

Thule, Greenland +4C,  Alert, Ellsmere -32 C.

[RaenorShine]

Still no updates on the NSIDC site (still showing 14 March)

DMI is showing a large area of negative mass balance on the west coast for 17/3, and to a lesser extent on the east. Still overall net mass gain over the whole of Greenland due to snow in the north.

[Carex]

From NSIDC

"The Greenland Today melt detection program is being corrected. Conditions in the snow in southeastern Greenland are unusually warm below the surface, but the surface has in general not been melting. Adjustments to the melt mapping software are being implemented, and we will post a discussion on the correction either later today or by the end of tomorrow at the latest at
http://nsidc.org/greenland-today/.

Please see the discussion once it is posted for further details.

Best regards,
Lisa
NSIDC User Services"

[AndrewP]

"The surface has generally not been melting"

I have been making this argument for the past month on another site. This really should not come as a surprise to the unbiased observer. The temperature recordings above freezing were from sea level, on the coast, and off the ice sheet. Another poster above (diablobanquisa) showed that even many of these places had not risen above freezing. Only the warmest locations on the continent had risen above freezing, and only by small to moderate margins.  Anybody familiar with a winter climate knows temperatures in the 30s and 40s don't cause much melt. That takes temperatures in the 50s and 60s. Warm winters in Greenland are likely beneficial to mass balance due to an association with heavier snowfall. NSIDC confirmed in their statement that snowfall has indeed been heavy this winter.

The only possible negative is there could be some very small areas that were hit by the warmth the hardest with low snow depths which will cause some local albedo issues. But I'm not even convinced that the few locations that saw some some 40s and some rain didn't also see more snow than normal.

[diablobanquisa]

NSIDC has posted the discussion about the adjustment: An early spring re-calibration for melt detection

[Jim Williams]

NSIDC has posted the discussion about the adjustment: An early spring re-calibration for melt detection

So....No actual surface melt, but the whole snowbank was still wet all last year.  Sort of like damning with faint praise.

[Jim]

...So, it is a recalibration.
The reasons given at the NSIDC website are worrying for the spring/summer melt season, as there does appear to be a substantial amount of near-surface snow and ice close to freezing point. Once the top layer of this years snow has melted, this lower level will surely be quick to melt out and contribute to a melt this season that could easily exceed last years melt by a considerable margin.
The next few months will be very interesting indeed!

[RaenorShine]

NSIDC has just published the data up to the 18th. 

The previous data didn't really make sense given the weather information.  It's interesting that the measurements need to be re-calibrated every year to ensure that the melt/no melt reading is correct.

It still shows very little melt (none on the 18th at all) despite the high temperatures on the SW coast over the past couple of days.

DMI is still showing slight mass loss (melt) across a large area along the SW coast for the 18th.

It will be interesting to follow these over the next couple of months to see the differences.

[AndrewP]

...So, it is a recalibration.
The reasons given at the NSIDC website are worrying for the spring/summer melt season, as there does appear to be a substantial amount of near-surface snow and ice close to freezing point. Once the top layer of this years snow has melted, this lower level will surely be quick to melt out and contribute to a melt this season that could easily exceed last years melt by a considerable margin.
The next few months will be very interesting indeed!

Except that even if the snow and ice is 5C warmer than normal that is only excess energy of 2.5cal/g, whereas the energy required to actually melt it is a whopping 80cal/g. So the head start is tiny compared to the energy required to actually melt ice.

In addition, the sub-surface temperature anomaly will likely continue to be reduced until the start of melt season.

[frankendoodle]

The early melting seems to have stopped in mid march.
http://nsidc.org/greenland-today/
Just like in the northern USA, the second half of march was colder than Dec thru Feb.

[silkman]

Temperatures in SW Greenland are higher than in the UK today. 11C in Nuuk right now with freezing levels above 1000m and it's going to stay that way for a few days. Snow cover is already low. An early start to the melt season seems likely.

http://www.weather-forecast.com/locations/Godthaab/forecasts/latest

[Jim Hunt]

Temperatures in SW Greenland are higher than in the UK today.

They certainly are!

http://econnexus.org/the-economist-being-economical-with-the-truth-about-climate-change/#comment-26470

Does anybody here agree with the leader writer at The Economist who put into print that "climate change has 'plateaued'"?

[Buddy]

I haven't read the article in the Economist....but something plateauing, is something far different than something STOPPING, or something REVERSING.  I think it's reasonable to say that air temperatures have PLATEAUED over the last 10 years (albeit SLIGHTLY RISING).  But I think we can point to at least 3 causes for the "slight pause" or plateau:  (1) volcanic activity, (2) aerosol's from Asia (especially China), (3) more heat absorbed by the deep ocean (as noted in a recent research article).

When China starts to clean up their air quality....that will allow more heating, just when we don't need it.

[silkman]

Jim

I certainly don't agree with the idea that climate change has plateaued. We're just storing up more problems for the future!

https://forum.arctic-sea-ice.net/index.php/topic,168.0.html

[werther]

MODIS is showing melt features at 900-1000 m +SL SEast of Sermeq Kujalleq. This looks very anomalous...

[Jim Hunt]

As you've probably gathered, I've been looking at that too Werther.  It doesn't register on the newly recalibrated "melt map" though?

[RaenorShine]

The DMI site is showing negative mass balance down most of the west coast at the moment, with some areas showing over 4-8mm water loss per day.

If the NSIDC survey was too sensitive before, have they now turned down the gain too much now? 

I guess we'll see as the melt season progresses, since the recalibration DMI have been showing more and more melt, but showed very little before that.

[Jim Hunt]

I'm no expert in these matters, but DMI show "snow melt", whereas NSIDC are endeavouring to reveal "ice melt"?

[Jim]

Hi Jim,
Looks like some more melting now, I wonder if we'll get another all-surface melt like last year?