AvantHiatus Posted July 13, 2014 Share Posted July 13, 2014 Except there are no signs of the AMO going predominantly negative. It's still most likely locked into the warm phase well into the next decade. The Central Atlantic cold pool is at its weakest extent since 2012. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 13, 2014 Author Share Posted July 13, 2014 Yeah the NATL has warmed quite a bit. 2013 had a relatively strong AMO+. This year it's been lower but is now positive and will likely be .15-.20C+ in July. Current SSTA trends are reflective of this. Link to comment Share on other sites More sharing options...
PhillipS Posted July 13, 2014 Share Posted July 13, 2014 A discussion that we seem to have here every year is that surface melt is only one of several factors affecting the mass balance of the GIS - and in recent years surface melt isn't even the dominant factor. So focusing on surface melt, as shown in the NSIDC plots, gives an impression that is at best incomplete and at worst is dishonest. To get a more accurate idea of the GIS conditions two factors to monitor are glacial movement and calving, and precipitation (snow in the winter, and both rain and snow in the summer). Some of the recorded calving events have removed tens of cubic kilometers of GIS ice in the space of a few hours. Rain both melts snow directly and transports slush to lower elevations where it will melt and runoff without refreezing. A good site for monitoring net GIS mass balance is Polarportal.dk which is run by the Danish Meteorlogical Institute. Here is their plot of the net mass balance of the GIS for 2014: As you can see, 2014 is slightly ahead of 2012, the previous record year. If one only looked at surface melting this would come as a surprise. We can also look at their plot of the monthly mass changes: For much of Spring 2014 the GIS was losing mass as fast or faster than it did in 2012 so it really isn't surprising that 2014 is leading so far. But mass loss has slowed a bit for the last four weeks so I won't be astonished if 2014 ends with less mass loss than 2012. On the other hand, a warm August and September and / or a few large calving events and 2014 could set a new record mass loss. For an awesome video of the largest calving event ever caught on film check out this youtube video. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 13, 2014 Author Share Posted July 13, 2014 Adding to Phillips post. The areas where melt matters except the cooler air over N. GIS are warm and albedo has been lowered substantially already. 90% of the surface ice mass loss on GIS is from 15% of the ice sheet which is located below 1500M. The models are quite warm over GIS for a +NAO regime incoming. Especially the Southern half. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 13, 2014 Author Share Posted July 13, 2014 I should say it's already a +NAO barely. But July has seen albedo plummet with mostly +NAO conditions. However these are not 2013 like +NAO conditions. The Western GIS lower albedo layer has been well exposed for a while now with melt lakes. The biggest difference for 2014 versus the bigger -NAO years is the Northern side of GIS has seen strong melt below 1250-1500M. Strong enough for June albedo to come in 3rd lowest on record over GIS. July saw albedo drop hard at the start of the month and we haven't seen any change in that. Link to comment Share on other sites More sharing options...
PhillipS Posted July 14, 2014 Share Posted July 14, 2014 Bluewave - my understanding is that the MODIS values are periodically recalibrated using the GRACE data. Is that possibly the reason for the adjustments? I think it's an excellent question though. Have you ocnsidered emailing the DMI and asking for an explanation? The contact info is given on Polarportal. If you do write, please share any response you get. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 14, 2014 Author Share Posted July 14, 2014 DMI revamped their model lowering how much top melt they believe is taking place and have placed more of the ice loss in the calving of glaciers that is what was said on Nevens forum. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 14, 2014 Author Share Posted July 14, 2014 Good for the arctic bad for the GIS and regional land ice especially the EURO. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 19, 2014 Author Share Posted July 19, 2014 While the arctic gets a much needed reprieve from big melt. GIS is about to get clobbered again. Melt area has been below normal for about 7-8 days since June 1st. Ouch. I would expect 30-50% the next 7-8 days again after tomorrow. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 19, 2014 Author Share Posted July 19, 2014 To compound the GIS torching smoke from wildfires is being pulled into GIS between an SLP and HP. So much so it's visible on todays sat images. Ouch. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 19, 2014 Author Share Posted July 19, 2014 SSTS in the Baffin are way above normal. The entire West coast of GIS has 5-7C+ ssts right now over a large area in the Baffin. Well above normal. Either side where warm air advection comes the next 10 days will come from areas of water well above normal.. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 20, 2014 Author Share Posted July 20, 2014 Record warmth over SW and NE GIS is a possibility over the next 7 days. The pummeling is underway and starts in earnest tomorrow. SW GIS where the albedo is already well below the 2000-2009 normals gets totally smoked with the mean flow S/SW/SSW over the next 3-4 days at least. We are talking about surface temps in the 500-1200M range reaching upper 40s to near 55F+ over the dark ice. We will have to track promice stations. But when temps get up into the 10-12C+ range ice mass loss goes beserker. Remember this is peak ice mass loss time. So it's all compounded this is the worst time of year for a heat wave like this to take shape. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 20, 2014 Author Share Posted July 20, 2014 Day one and temps are already in the mid 50s to upper 60s up and down the West coast of GIS. mid to upper 60s South coast and low to mid 50s SE side. The record high at station KAN_B on the West coast of GIS within the dark ice region is 15.1C set in 2011. Yesterday Kan_B made it to 10C. 1500M temps in the area are expected to go above 10C at times this week. http://promice.org/WeatherArchive.html?promiceStationStationid=203&stationid=203 SSTS are now pushing the 7-8C+ range along the West coast of GIS. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 21, 2014 Author Share Posted July 21, 2014 It took one day into the GIS torching for **** to hit the fan. Absolutely nasty and the torching is just getting going. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 21, 2014 Author Share Posted July 21, 2014 Hmmm. Not sure how this comes to this conclusion so far. Maybe it incorporates glacial calving. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 21, 2014 Author Share Posted July 21, 2014 9C sst reading off the West coast of GIS with the strip of 7C+ still up and down the West coast. That is brutal. Melt area will take off today and likely jump well above 30% by tomorrows update. Either way the hotspots where almost all of the melt takes place are getting roasted. The forecast show Northern GIS gets a break for a day or so. It's gentler slopes expose a larger area of GIS surface to melt in the 200-1000M layer. The SW/SE/W/E sides of GIS are under the gun throughout. This is a perfect storm of multiple bad combos to get big gis topical ice mas loss. An early scan from Jaxa today shows the entire Southern part of GIS and SW part having surface melt so far today. The melt up above 2000M is essentially an albedo exercise in terms of dropping albedo. But in the 1500M or less areas it's balls out melt and lowering of albedo. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 21, 2014 Author Share Posted July 21, 2014 Soundings around the Southern 1/2 of GIS at 12z today show the freeze level is around 2700-3000M. On the NE side it's around 3000M as well. Alert, Canada just NW of GIS shows it around 2250M. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 21, 2014 Author Share Posted July 21, 2014 Land glaciers seperate from GIS ice sheet itself but over parts of the rocky shore of GIS show how they are quickly shrinking. We can't see the actual elevation. Some of these bodies of ice are very thick. Others less. But all of them are shrinking. Thanks to Epson Olson for the animation. Washington Land situated between Petermann Gletscher to the north, Humboldt Gletscher to the south and Nares Strait to the west, and a future large island when the ice is gone.Over the last 38 years we can watch how the ice fields (iskapper) are getting smaller and smaller: Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 25, 2014 Author Share Posted July 25, 2014 On the 22nd Summit recorded a high of 1C. That's one hell of a temperature at 3200M (10,500 ft) elevation anywhere in the world. Is anyone aware of whether the elevation at the Saddle is increasing or decreasing? GIS broke freezing at the summit. Link to comment Share on other sites More sharing options...
chubbs Posted July 27, 2014 Share Posted July 27, 2014 Plot of weather conditions at Greenland summit station over past month. As posted above brief spike above freezing on the 22nd with another spike to 30 earlier in the month. Relatively warm over past couple of days with little diurnal range and high dew point - probably fogged in. Link to comment Share on other sites More sharing options...
tacoman25 Posted July 27, 2014 Share Posted July 27, 2014 I realize that 1C is pretty warm for the summit in Greenland, but whoever made the comment that getting above freezing at 10,500 is impressive anywhere in the world...that's not actually even close to the case. Here in CO, for example, it regularly gets into the 70s at 10,500 feet. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 28, 2014 Author Share Posted July 28, 2014 GIS on DMI is running with 2012. But I doubt 2014 keeps up. Albedo has dropped big time the last 7 days. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 30, 2014 Author Share Posted July 30, 2014 Hey Phillip. Can you explain again how this graphic works? It appears this year is about to fall behind 2012 which isn't surprising. Gis ice mas loss this season has been driven by albedo and warm conditions where melt is the strongest. Link to comment Share on other sites More sharing options...
PhillipS Posted July 31, 2014 Share Posted July 31, 2014 Here is the description of the charts from the PolarPortal website: Maps, figures and curves illustrate different aspects of the total change in mass of the Greenland Ice Sheet. Here you can follow how the ice sheet gains mass through snowfall accumulating on the surface and how it shrinks through melting from the surface and discharge of icebergs from glaciers that end in the sea. The curves and maps are: The tab ”Accumulated” illustrates the total change in accumulated mass of the Greenland Ice Sheet over the year. The tab ”Per month” illustrates the total mass changes per month. Let's look at monthly first: IMO this chart is confusing for several reasons - 1) it shows the monthly GRACE values as a line instead of as points or bars; 2) the legend indicates the 2014 GRACE data will be a colored dot, but it's not plotted that way; 3) the plot mixes daily MODIS values with monthly GRACE values and would be clearer (apples to apples) if the MODIS data were also averaged into monthly values. There is certainly room for improvement. Still, there is much that can be learned from this plot: The GIS monthly mass balance was positive until late April, after which 2014 had a higher rate of loss than 2012 for several months. July is the peak month for GIS mass loss, with the long-term monthly net loss rate for July around 180 km3. After July the rate of loss slows quickly, going positive in October and remaining positive through the rest of the year as snow accumulation becomes the dominant factor. July 2012 lost around 250 km3, and July 2014 lost around 220 km3 Similarly for the total mass change chart: The net mass balance is typically positive until early June and then goes negative as melting and calving erase the snow accumulation gains made over the winter. The net loss through July is similar for 2012 and 2014 at around 260 km3. This value is lower than I would expect from the montly chart but I don't have any insight into why that's the case. I agree that 2014 may end up a smaller net loss than 2012 but there are weeks left in the melt season and the Canadian wildfires may affect the outcome. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted July 31, 2014 Author Share Posted July 31, 2014 A little over a weeks worth of days of ever so slightly below average melt area. Add in Calving and albedo and GIS is having itself another big ice mass loss summer. Link to comment Share on other sites More sharing options...
chubbs Posted July 31, 2014 Share Posted July 31, 2014 Phillip The two charts you posted don't appear entirely consistent. The top chart shows 2014 with less melt than 2012 in mid-summer while the bottom chart shows 2014 pulling slightly ahead of 2012 in the same period. Any explanation?. Link to comment Share on other sites More sharing options...
PhillipS Posted July 31, 2014 Share Posted July 31, 2014 Phillip The two charts you posted don't appear entirely consistent. The top chart shows 2014 with less melt than 2012 in mid-summer while the bottom chart shows 2014 pulling slightly ahead of 2012 in the same period. Any explanation?. You're right - there appears to be an inconsistency between the two charts. I've sent an email asking for info and I'll post whatever response I get. But I'm not too hopeful because an earlier email never got a response. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted August 3, 2014 Author Share Posted August 3, 2014 That is awful. Link to comment Share on other sites More sharing options...
chubbs Posted August 8, 2014 Share Posted August 8, 2014 Melt has been well above normal since early July on DMI chart. In a normal year melt season would be just about over. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted August 8, 2014 Author Share Posted August 8, 2014 Albedo being wrecked is the key to the GIS ice sheet. It's a game changer. The lower albedo over the Northern part of GIS is quite astonishing. In the waning sun it being 15-20%+ lower than it was naturally 15-30 years ago and longer adds a tremendous amount of solar intake. The albedo based products tell the story. Link to comment Share on other sites More sharing options...
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