A link to the ground data collected along the K-transect by the Institute for Marine and Atmospheric Research Utrecht, Utrecht University, the Netherlands can now be accessed through a new link under the Data section. An example of the available plots is reported on the left. The institute has been operating several automatic weather stations on the western Greenland ice margin (K-transect) for many years and the data of the current calendar year can be viewed from the link under Data or here. Thanks to Carleen Tijm-Reijmer (IMAU) for sending the link. 

Here's a link to Jason Box 2012 analysis of albedo over the Greenland ice sheet. The reduction of the albedo is a critical factor for enhancing melting over the Greenland ice sheet. The image on the left shows the ice sheet albedo time series updated through July 2012 by Jason Box. 

To better understand the importance of this mechanism you can check a recently published paper on the Cryosphere Discussion by Box et al. (2012) in which we focus on this problem or another paper (Tedesco et al., 2011) that we published on Environmental Research Letters focusing on the role of albedo and accumulation on the 2010 melting recording in Greenland. Both papers are also available in the Scientific Literature section of this site. 

The plot also shows that the event of July 2012 s unique for the satellite era (1979 - to date) and it lasted for a few days. For those who are not expert in passive microwave remote sensing: as the liquid water appears, the recorded signal jumps to high values, suddenly. This kind of change (sudden and strong) can be related only to the appearance of  liquid water within the snowpack as other changes in the physical properties of the snowpack would produce either a weaker signal or would have a different timescale. Note: this sensitivity of microwaves to water is the same physical principle through which we are able to cook our food using microwave ovens !

ORIGINAL MESSAGE FROM CHRIS TO CRYOLIST 

For those of you interested in the reported air temperatures at Summit, the NOAA data for 2012 is illustrated here relative to several previous years of their JJA data (up to July 25th so far).
http://jcet.umbc.edu/2012/07/nasa-72412-press-release-green.html

The data shown will be updated periodically through the end of August. And it bears repeating that the snow surface temperature (as tracked by MODIS or the passive microwave sensors, see the NASA press release) can differ by several degrees from the nominal 2 meter air temperature.

Cheers, Christopher

-- 
Christopher A. Shuman - Assoc. Research Scientist
UMBC Joint Center for Earth Systems Technology
Cryospheric Sciences Laboratory, Code 615
Greenbelt, MD 20771 - USA
(301) 614-5706 voice (301) 614-5666 fax
Christopher.A.Shuman@nasa.gov

The image below shows the cumulative number of melting days over Greenland for the period June 1st - July 25th. Beside the large melt extent occurring in July 2012, note the high number of melting days along the southeast coast as well as the width of the area subject to considerable melting along west Greenland. Over the southeast coast, during the period June 1st - July 25th, melting lasted up to 30 days above the mean.

Since the past  week or so, melting has decreased with respect to the breaking-record values of June and mid July, mostly as a consequence as the shift to a neutral phase of the NAO. Depending on how melting will evolve in August, the 2012 melting season might set a new melting record. Nevertheless, 2012 is already positioning among the top melting years, with the cumulative melting index until July 25th being close to the cumulative melting index for the whole 2010 and higher than the one for the 2011 season.