Subglacial processes

Image of the Week — Microbes munch on iron beneath glaciers

Sophie Nixon March 31, 2017

Experiment showing that microbes in subglacial sediment reduce more iron when it's colder (blue lines, i.e. 4°C ) than when it's warmer (red lines, 15°C.) [Credit: adapted from Nixon et al, (2017) Fig.1] Click here here to enlarge the image.

The interface between a glacier and its underlying bedrock is known as the subglacial zone. Here lie subglacial sediments, the product of mechanical crushing of the rock by the glacial ice. Despite their lack of sunlight, nutrients and oxygen, subglacial sediments host active and diverse communities of microorganisms. What we (don’t) know about subglacial microorganisms The past few decades ...[Read More]

Image of The Week – Plumes of water melting Greenland’s tidewater glaciers

Donald Slater October 28, 2016

Loss of ice from The Greenland Ice Sheet currently contributes approximately 1 mm/year to global sea level (Enderlin et al., 2014). The most rapidly changing and fastest flowing parts of the ice sheet are tidewater glaciers, which transport ice from the interior of the ice sheet directly into the ocean. In order to better predict how Greenland will contribute to future sea level we need to know mo ...[Read More]

Image of the Week: Under a Glacier

Nanna B. Karlsson October 16, 2015

Under the Hochjochferner glacier. Credit: Ilkka Matero.

What is happening under a glacier? This is a difficult questions to answer as accessing the glacier bed is usually not that easy. Here, we are getting a rare glimpse of the different processes and materials that are often found at the ice-bed interface. The photograph shows both sediments and hard rock, clear ice and dirty ice, and of course flowing water. No wonder these processes are complicated ...[Read More]