Jason Box: The News from Narsarsuaq

August 17, 2013

20130815192704-1024x680

Coming in to land at a PROMICE climate station, one of 22 on Greenland ice operated by GEUS. Photo J. Box.

Dark Snow Project Blog:

I’m spending a week flying out of Narsarsuaq, south Greenland, with colleague Dr. Robert Fausto, to maintain climate stations equipped to monitor surface ice melt in great detail. Part of the Danish PROMICE network, the stations obtain surface energy and mass budget closure. The closure means that calculated melt matches with observed melt.

Flying across this vast space and on the ground, I’m is struck by how abundant snow algae and other light absorbing impurities can be. The low reflectivity impurities amplify the effects of the increasing melt season. Increased melt means a shorter duration of highly reflective snow cover. The prolonged exposure of an impurity-rich bare ice surface multiplies melt rates. I’ve calculated that without this albedo feedback, the increase in melt rates would amount to half of what’s observed. Some of this feedback is due to ice crystal rounding. Some is due to the impurities. Measuring the relative importance of metamorphic and impurity driven albedo reduction is a subject of our work.

20130815181506-1024x741

Boots on the ice offer a close look (and to sample) impurities concentrating at the surface. The fact is, much of this dark material is from cyanobacteria and blue-green algae. Photo J. Box.

20130815181438-1024x660

Puddles often form with this kind of ‘algal slick’. Photo J. Box.

It’s exciting to be working with Dr. Marek Stibal who studies the microbial environment on Arctic ice. Together with his data, the surface energy exchange data from the PROMICE climate stations and Danish Meteorological Institute’s regional climate modeling (Follow @Greenlandsmb), we have a powerful approach to unravel more detail from the melt story in Greenland.

20130815135807-1024x680

South Greenland Dark Ice. Photo J. Box.

20130815140253-1024x680

Snow accumulates in crevasses forming snow bridges that one would rather fly over. In between, impurity-rich ice absorbs up to 80% of the Sun’s energy. Photo J. Box.

20130815140341-1024x680

Surface melt water mingles with impurity rich Greenland ice. Photo J. Box.

nars1

Robert Fausto maintains a climate station equipped to measure downward and upward solar energy, among many other climate parameters as part of the Danish PROMICE network (Follow @PromiceGL). Photo J. Box. (Follow @Climate_Ice)

 

About these ads

3 Responses to “Jason Box: The News from Narsarsuaq”


  1. […] Dark Snow Project Blog:I’m spending a week flying out of Narsarsuaq, south Greenland, with colleague Dr. Robert Fausto, to maintain climate stations equipped to monitor surface ice melt in great de…  […]


  2. […] I’m spending a week flying out of Narsarsuaq, south Greenland, with colleague Dr. Robert Fausto, to maintain climate stations equipped to monitor surface ice melt in great detail. Part of the Danish PROMICE network, the stations obtain surface energy and mass budget closure. The closure means that calculated melt matches with observed melt.Flying across this vast space and on the ground, I’m is struck by how abundant snow algae and other light absorbing impurities can be. The low reflectivity impurities amplify the effects of the increasing melt season. Increased melt means a shorter duration of highly reflective snow cover. The prolonged exposure of an impurity-rich bare ice surface multiplies melt rates. I’ve calculated that without this albedo feedback, the increase in melt rates would amount to half of what’s observed. Some of this feedback is due to ice crystal rounding. Some is due to the impurities. Measuring the relative importance of metamorphic and impurity driven albedo reduction is a subject of our work.Click headline to read more and view pix–  […]


Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Follow

Get every new post delivered to your Inbox.

Join 1,664 other followers

%d bloggers like this: