EGU Guest blogger

Image of the Week – The birth of a sea-ice dragon!

Kevin Bulthuis June 30, 2017

Fig. 1: Dragon-skin ice observation in Terra Nova Bay by the Nathan B Palmer research team in April 2017. [Credit: IMAS ].

Dragon-skin ice may sound like the name of an episode of the Game of Thrones fantasy franchise. However, this fantasy name hides a rare and bizarre type of ice formation that you can see in our Image of the Week. It has been recently observed by the “Polynyas, ice production and seasonal evolution in the Ross Sea” (PIPERS) research team in Antarctica. This bizarre phenomenon caused by ...[Read More]

Image of the Week – Heat waves during Polar Night!

François Massonnet June 23, 2017

The winter 2016-2017 has been one of the hottest on record in the Arctic. In our Image of the Week, you can see that air temperatures were positive in the middle of the winter! Let’s talk about the reasons and implications of this warm Arctic winter. But first, let’s take a tour in Svalbard, the gateway to the Arctic… A breach in the one of the world’s largest seed vaults The Global S ...[Read More]

Image of the Week – When the dirty cryosphere destabilizes!

Laura Helene Rasmussen June 16, 2017

Figure 1: Thermokarst development due to melt and drainage of below-ground massive ice, NE Greenland [Credit: Laura Helene Rasmussen]

Ice is usually something you see covering large ocean areas, mountain tops and passes or as huge sheets in polar regions. This type of ice is clearly visible from space or with the naked eye. There is, however, a large volume of ice that is less visible. This ice is distributed over the polar and high alpine permafrost regions; and is the ice hidden below ground. It might be hidden, but that doesn ...[Read More]

Image of the Week – Far-reaching implications of Everest’s thinning glaciers

Scott Watson June 9, 2017

From 1984 to 2015, approximately 71,000 Olympic size swimming pools worth of water were released from the melting Khumbu Glacier in Nepal, which is home to Everest Basecamp. Find out how Himalayan glaciers are changing and the implications for downstream communities in this Image of the Week. Himalayan glaciers supply freshwater Himalayan glaciers supply meltwater for ~800 million people, includin ...[Read More]

Image of the Week – Ice lollies falling from the sky

David Docquier June 2, 2017

You have more than probably eaten many lollipops as a kid (and you might still enjoy them). The good thing is that you do not necessarily need to go to the candy shop to get them but you can simply wait for them to fall from the sky and eat them for free. Disclaimer: this kind of lollies might be slightly different from what you expect… Are lollies really falling from the sky? Eight years ag ...[Read More]

Image of the Week – How geometry limits thinning in the interior of the Greenland Ice Sheet

Denis Felikson May 26, 2017

Figure 1: (a) Mass change of the Greenland ice sheet measured by NASA’s GRACE mission in cm/yr water equivalent from January 2003 to December 2013 [Credit: modified from Velicogna et al., 2014]. (b) Dynamic surface elevation change and mass loss along the margin of West Greenland as measured by DEM differencing. The map shows surface elevation change from 1985 to present for 16 outlet glaciers. Circles represent mass change (estimated using 917 kg m-3 as ice density) with circle areas proportional to magnitude of mass change. [Credit: Denis Felikson]

The Greenland ice sheet flows from the interior out to the margins, forming fast flowing, channelized rivers of ice that end in fjords along the coast. Glaciologists call these “outlet glaciers” and a large portion of the mass loss from the Greenland ice sheet is occurring because of changes to these glaciers. The end of the glacier that sits in the fjord is exposed to warm ocean water that can me ...[Read More]

Image of the Week – Antarctica’s Flowing Ice, Year by Year

George Roth May 12, 2017

Today’s Image of the Week shows annual ice flow velocity mosaics at 1km resolution from 2005 to 2016 for the Antarctic ice sheet. These mosaics, along with similar data for Greenland (see Fig.2), were published by Mouginot et al, (2017) last month as part of NASA’s MEaSUREs (Making Earth System Data Records for Use in Research Environments) program. How were these images constructed? The mosaics s ...[Read More]

Image of the Week – A high-resolution picture of Greenland’s surface mass balance

Brice Noël April 14, 2017

Fig. 1: Surface mass balance (SMB) of the Greenland ice sheet and peripheral ice caps at 1 km resolution averaged for 1958-2015. The interior of the ice sheet (blue) accumulates mass from snowfall whereas the narrow margins (red) lose mass from runoff of meltwater. Yellow dots locate on-site measurements. At this resolution, the small ice caps and marginal glaciers are accurately resolved [Credit: Brice Noël]. Click here here to enlarge the image.

The Greenland ice sheet – the world’s second largest ice mass – stores about one tenth of the Earth’s freshwater. If totally melted, this would rise global sea level by 7.4 m, affecting low-lying regions worldwide. Since the 1990s, the warmer atmosphere and ocean have increased the melt at the surface of the Greenland ice sheet, accelerating the ice loss through increased runoff of meltwater and i ...[Read More]

A year at the South Pole – an interview with Tim Ager, Research Scientist

Tim Ager April 6, 2017

Tim Ager spent over a year working as a research scientist at Amundsen-Scott South Pole Station

What is it like to live at the South Pole for a year? A mechanical engineer by trade, Tim Ager, jumped at the opportunity to work for a year as a research scientist at Amundsen-Scott South Pole Station. When not traveling on various adventures he lives in Austin, Texas, and recently took the time to answer a few questions about his time at Pole. What goes on at Amundsen-Scott South Pole Station? ...[Read More]

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]