CR
Cryospheric Sciences

Regular Editor

Image of the Week – Let it snow, let it snow, let it snow…

December 23, 2016
Image of the Week – Let it snow, let it snow, let it snow…
Probability of a White Christmas in the USA (based on weather data from 1981-2010). [ Credit : National Climate Data Center, NOAA. Via Wikimedia Commons]

Christmas is coming to town and in the Northern Hemisphere many of us are still dreaming of a white Christmas, “just like the ones we used to know”. But how likely is it that our dreams will come true? What is the definition of a White Christmas ? Usually Christmas can be defined as a “White Christmas” if the ground is covered by snow on either Christmas Eve or Christmas Day depending on local tra ...[Read More]

Image of the Week – Sea Ice Floes!

December 2, 2016
Image of the Week – Sea Ice Floes!
Left: Floes in the Southern Ocean surrounding the Nathaniel Palmer, taken by a multi-rotor drone. The length of the Nathaniel Palmer, about 100 m, is shown for comparison [Credit: EOS]. Right: Floes in the Bering Strait in May, 2000 from the MODIS satellite. Arrow shows the width of the Bering Strait, 85 km, for comparison [Credit: NASA Earth Observatory].

The polar regions are covered by a thin sheet of sea ice – frozen water that forms out of the same ocean water it floats on. Often, portrayals of Earth’s sea ice cover show it as a great, white, sheet. Looking more closely, however reveals the sea ice cover to be a varied and jumbled collection of floating pieces of ice, known as floes. The distribution and size of these floes is vitally imp ...[Read More]

Image of the Week – The Polar Hole!

October 14, 2016
Image of the Week – The Polar Hole!
Figure 1: Mean sea-ice thickness for November 2010 from CryoSat-2 satellite measurements. [Credit: The data processing of CryoSat-2 sea-ice thickness is funded by the German Federal Ministry for Economic Affairs and Energy (Funding: 50EE1008) and data of November 2010 are provided by meereisportal.de (Funding: REKLIM-2013-04) ].

Have you ever stumbled upon a satellite picture showing observations of the Arctic or Antarctic? You often see a circle where there is no data around the exact location of the geographic pole – as you can see in our Image of the Week. A few days ago, I wanted to explain this to one of my friends and turned to my favourite search engine for help. My search turned up a tremendous amount of sto ...[Read More]

Image of the Week – Yes, you’re looking at one of Peru’s most dangerous glacial lakes!

September 9, 2016
Image of the Week – Yes, you’re looking at one of Peru’s most dangerous glacial lakes!
Lake Palcacocha is one of Peru’s most dangerous glacial lakes due to the threat of an avalanche entering the lake and causing a glacial lake outburst flood. The siphons installed in 2011 lowered the level of the lake by 3-5 m in an attempt to reduce the flood hazard of the lake. [Credit: David Rounce]

As mountain glaciers melt and recede, they often leave behind large glacial lake that are contained by the glaciers’ old terminal moraines. These glacial lakes are found throughout the world and can pose a significant flood hazard to downstream communities and infrastructure. The image of this week focuses on Lake Palcacocha, a large glacial lake located in Peru’s Cordillera Blanca at an elevation ...[Read More]

Image of the Week – The Journey of a Snowflake

September 2, 2016
Image of the Week – The Journey of a Snowflake
Figure 1: Snowflakes viewed with a low temperature scanning electron microscope (SEM). [ Credit : Agricultural Research Service, United States Department of Agriculture via Wikimedia ]

You remember last winter, when everything was white and you had so much fun building a snowman with your friends? What you see on this image above, is what you would see, if you took a tiny tiny piece of your snowman and put it under a low-temperature scanning electron microscope (SEM). The colours are called “pseudo colours”, they are computer generated based on the number of electron ...[Read More]

Image of the week – Our salty seas and how this affects sea ice growth

August 5, 2016
Image of the week – Our salty seas and how this affects sea ice growth
Lines of constant density for sea water . Black lines show lines of constant density as a function of temperature (y-axis) and salinity (x-axis). The dashed black line indicates, for a given salinity, the temperature at which the water will freeze. Figure adapted from Timmermans and Jayne (2016) - with permission.

Earth’s oceans are not simply just water, they are a complicated multi-component fluid consisting of water and dissolved salts (ask anyone who has tried to drink it!). The existence of these salts has a significant impact on global ocean circulation. Nowhere is this more significant than in the polar oceans where it is one of the key factors influencing sea ice formation. In this week’s imag ...[Read More]

Image of the Week — Looking for ice inside a volcano !

July 29, 2016
Image of the Week — Looking for ice inside a volcano !
A phase of the laser scanning survey of the southernmost ice mass in Europe: the Ice Cave, Mount Etna,. [Credit: Alessio Romeo – Inside The Glaciers Project]

Who would think that one of the world’s most active volcano shelters the southernmost persistent ice mass in Europe!? Yes, you can find ice inside Mount Etna! Located at an altitude of about 2,040 m above sea level, the Ice Cave  (Grotta del Gelo) is well known among Mt Etna’s volcanic caves due to the presence of columns of ice on its walls and floor which occupy about the 30% of the ...[Read More]

Fieldwork at 5,000 meters in altitude

July 28, 2016
Fieldwork at 5,000 meters in altitude
Field Site, Imja Lake, in November 2015 [Credit: D. Rounce]

Imja Lake is one of the largest glacial lakes in the Nepal Himalaya and has received a great deal of attention in the last couple decades due to the potential for a glacial lake outburst flood. In response to these concerns, the UNDP has funded a project that is currently lowering the level of the lake by 3 m to reduce the flood hazard. The aim of our research efforts is to understand how quickly ...[Read More]

Image of the Week – How ocean tides affect ice flow

July 8, 2016
Image of the Week – How ocean tides affect ice flow
(a) Shaded relief map of Rutford Ice Stream (West Antarctica) and surrounding area. Red box indicates the region shown in b. (b) Horizontal velocity where colors indicate speed, arrows show flow direction, and grayscale background is horizontal speed from Rignot et al. (2011). (c) Detrended along-flow displacements measured with GPS stations beginning December 2003. Locations of stations are indicated in (b). ( Credit : Brent Minchew )

Ice streams discharge approximately 90% of the Antarctic ice onto ice shelves , and ultimately into the sea into the sea (Bamber et al., 2000; Rignot et al., 2011). Whilst flow-speed changes on annual timescales are frequently discussed, we consider here what happens on much shorter timescales! Previous studies have shown that ice streams can respond to ocean tides at distances up to 100km inland ...[Read More]

Image of The Week – A Game of Drones (Part 1: A Debris-Covered Glacier)

July 1, 2016
Image of The Week – A Game of Drones (Part 1: A Debris-Covered Glacier)
Figure 1: Down-glacier view of debris-covered Miage Glacier, Italy, taken from a low-altitude lightweight UAV in June 2016 (Credit: M. Westoby). As the summer progresses, the melting of winter snow cover prompts the development of a surface drainage network, characterised as a network of streams and ponds, which are concentrated in intermoraine troughs and drain into open crevasses or moulins. Snowmelt in this area will eventually reveal a glacier surface covered by a continuous mantle of supraglacial debris, comprised predominantly of mica-schist

What are debris-covered glaciers? Many alpine glaciers are covered with a layer of surface debris (rock and sediment), which is sourced primarily from glacier headwalls and valley flanks. So-called ‘debris-covered glaciers’ are found in most glacierized regions, with concentrations in the European Alps, the Caucasus, Hindu-Kush-Himalaya, Karakoram and Tien Shan, the Andes, and Alaska and the weste ...[Read More]