Cryospheric Sciences

Image of the week – The winds of summer (and surface fluxes of winter)

Céline Heuzé July 22, 2016

Representation of the (a) summer and (b) winter oceanic circulation within the Adélie region, East Antarctica. MGT = Mertz Glacier Tongue (red dot on the Antarctica map); other acronyms indicate different water masses: Antarctic Surface Waters (AASW), Modified Circumpolar Deep Water (MCDW*), Dense Shelf Water (DSW) and Antarctic Bottom Water (AABW) explained below. [Credit: reprinted with permission from Snow et al. (2016, figure 4) ]. Click here here to enlarge the image.

Antarctica is separated from the deep Southern Ocean by a shallow continental shelf. Waters are exchanged between the deep ocean and the shallow shelf, forming the Antarctic cross-shelf circulation: Very dense waters leave the shelf as Antarctic Bottom Water (AABW) that will then flow at the bottom of all oceans. Meanwhile, relatively warm water from the Southern Ocean, Modified Circumpolar Deep W ...[Read More]

Image of the Week – How ocean tides affect ice flow

Teresa Kyrke-Smith July 8, 2016

(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]

Marine Ice Sheet Instability “For Dummies”

David Docquier June 22, 2016

MISI is a term that is often thrown into dicussions and papers which talk about the contribution of Antarctica to sea-level rise but what does it actually mean and why do we care about it? MISI stands for Marine Ice Sheet Instability. In this article, we are going to attempt to explain this term to you and also show you why it is so important. Background The Antarctic Ice Sheet represents the larg ...[Read More]

An Antarctic Road Trip

Nanna B. Karlsson June 8, 2016

Arriving at our first drill site with our sledge containing drill equipment, survival box and of course our lunch. Credit: N. B. Karlsson

Working in the Arctic and Antarctic presents its own challenges. It is perhaps easy to imagine how a station situated close to the coast is resupplied: during the summer, one or more ships will arrive bringing fuel, food and equipment, but what about stations inland? Flying in supplies by aircraft is expensive and, in the case of large quantities of fuel, unsustainable. Besides, many stations are ...[Read More]

Image of the Week – Storing water in Antarctica to delay sea-level rise

David Docquier April 29, 2016

Difference in ice thickness from the initial equilibrium state after 100 years of ice addition (upper panels) and 1000 years after the end of the forcing (lower panels). Two scenarios are shown, 200 km (left panels) and 800 km (right panels) from the coastline, both corresponding to a sea-level mitigation of 10 mm per year (credit: Frieler et al., 2016, fig 3) .

Sea level rise Sea-level rise is one of the main impacts of the current global warming and its rate has dramatically increased in the last decades (the current rate is about 3 mm per year). Even if greenhouse gas emissions were stopped today, sea level would continue to rise due to the slow Earth climate system response (IPCC, 2013, chap. 13). It is therefore a considerable threat for popul ...[Read More]

Image of the Week: The Bipolar Seesaw

Nanna B. Karlsson April 8, 2016

Ice core records from the WAIS core showing fast millennial-scale climatic variability. Reprinted by permission from Macmillan (Publishers Ltd: Nature, WAIS Divide Project Members, 2015, vol. 520).

The colourful graphs above show how the climate changed in the period from 65 to 25 thousand years ago when Earth was experiencing an ice age. A wealth of information on the dynamics of our climate is embedded in the curves, especially how the northern and southern hemisphere interact, and how fast climate can change. The figure represents thousands and thousands of hours of work by scientists, te ...[Read More]

Image of the Week – Antarctic fieldwork 50 years ago!

Sophie Berger February 26, 2016

Rest break in the Sør Rondane Mountains, East Antarctica. Summer campaign 1964-1965 of the Belgian-Dutch Antarctic Expeditions (Credit: Jean-Jacques Derwael)

So far this blog has published many pictures of current polar field work campaigns. Today, we would like to take you back to Antarctic expeditions during the 1960s. The photos presented in this post date back from the Belgian-Dutch Antarctic field campaigns of 1964-1966. The first picture shows Ken Blaiklock (red overalls) with a Belgian surveyor. Ken was part of the 1955–58 Commonwealth Trans-Ant ...[Read More]

Image of Week: Blue Ice in East Antarctica

Nanna B. Karlsson January 22, 2016

Blue ice area in front of the northernmost part of the Heimefrontfjella, East Antarctica. Credit: N. B. Karlsson

The blue ice areas of Antarctica are one of the most fascinating parts of the ice sheet. In these regions, snowfall is so low that the ice is laid bare by the wind and consequently sublimates. This exposes beautiful, blue ice surfaces, like an ocean frozen in time. This picture was taken at a site named “Windy Corner” by the Kottas Mountains, in the northernmost part of the Heimefrontf ...[Read More]

Image of the Week — Happy New Year

Sophie Berger January 8, 2016

Night-owl unicorn in Antarctica. Credit: Brice Van Liefferinge

December 2014, 11:50 p.m., the sun licks the horizon on Derwael ice rise; It’s time to go back to the tent … The shot was taken during the 2014 IceCon Field campaign in East Antarctica (read Brice’s blog post telllling about his first journey to Antarctica). Here, you can also read about the 2016 field season of the IceCon project, which started just a few days ago.

Image of the Week — Greetings from Antarctica

Sophie Berger December 25, 2015

Credit: The British Antarctic Survey

Christmas greetings from people at Rothera Research Station, Adelaide Island, Antarctica. Rothera, which is the British Antarctic Survey’s largest base in Antarctica, is a centre for marine biology and gateway for getting scientists into their deep field camps. Christmas Day is a regular working day for the staff of around 90. However the chefs will be getting everyone into the festive spiri ...[Read More]