Microbes growing on glaciers are recognized for their importance in accelerating glacier melting by darkening their surface and for maintaining biogeochemical cycles in Earth’s largest freshwater ecosystem. However, the microbial biodiversity of glaciers remains mysterious. Today, new DNA sequencing techniques are helping to reveal glaciers as icy hotspots of biodiversity. To see a world in a grai ...[Read More]
Image of the week – Skiing, a myth for our grandchildren?
Skiing resorts might look very different in a few decades... [Credit: M. Cavitte]
Ski or water ski? Carnival season is typically when many drive straight to the mountains to indulge in their favorite winter sport. However, by the end of the century, models seem to predict a very different future for Carnival, with a drastic reduction in the number of snow days we get per year. This could render winter skiing something of the past, a bedtime story we tell our grandchildren at ni ...[Read More]
Image of the Week – The Gap, the Bridge, and the Game-changer
The Gap, the Bridge, and the Game-changer are three series of satellites. They carry instruments that measure the microwave radiation emitted by the Earth (called passive microwave instruments), while flying 800 km above our heads at 7,5 km/s. Since the late 1970s, most sea ice properties (concentration, extent, area, velocity, age and more!) have been measured with such passive microwave instrume ...[Read More]
Image of the week – How hard can it be to melt a pile of ice?!
Intriguing pile of ice in Gothenburg [Credit: C. Heuzé]
Snow, sub-zero temperatures for several days, and then back to long grey days of near-constant rain. A normal winter week in Gothenburg, south-west Sweden. Yet as I walk home in the evening, I can’t help but notice that piles of ice have survived. Using the equations that I normally need to investigate the demise of Greenland glaciers, I want to know: how hard can it be to melt this pile of ice by ...[Read More]
Image of the Week – Microbes have a crush on glacier erosion
This aerial image shows that Midtre Lovénbreen has shaped its catchment via erosion over thousands of years. [Credit: Andy Hodson]
Glacier erosion happens at the interface between ice and the ground beneath. Rocks are ground down to dust and landscapes shaped by the flowing ice. While these might be hotspots for erosion, the dark and nutrient-poor sites are unlikely environments for biological activity. However, experiments suggest there may be novel sources of energy powering subglacial microbial life… Where there is water, ...[Read More]
Image of the Week – Ice caps on Mars?!
Much like our Planet Earth, Mars has polar ice caps too, one for each pole: the Martian North Polar Ice Cap (shown on our image of the week) and the Southern Polar Ice Cap. Yet, their composition and structure reveals these ice caps are quite different from those of Planet Earth… Mars refresher As a refresher, here are some Mars facts: Mars is the 4th planet from the sun. Its equatorial dia ...[Read More]
Image of the Week – Arctic changes in a warming climate
Fig. 1: Schematic representation of major changes in the Arctic regions caused by global warming [Credit: Fig. 1.2 of AMAP (2017), adapted from US National Center for Atmospheric Research (NCAR)].
The Arctic is changing rapidly and nothing indicates a slowdown of these changes in the current context. The Snow, Water, Ice and Permafrost in the Arctic (SWIPA) report published by the Arctic Monitoring and Assessment Program (AMAP) describes the present situation and the future evolution of the Arctic, the local and global implications, and mitigation and adaptation measures. The report is base ...[Read More]
Image of the Week – Vibrating Ice Shelf!
Fig. 1: Geophones in the evening on the Ekström Ice Shelf, Antarctica. These devices are used to record seismic waves that are sent into the ice and bound back [Credit: Emma Smith]
If you listen carefully to the Ekström ice shelf in Antarctica, a strange sound can be heard! The sound of a vibrating truck sending sounds waves into the ice. These sound waves are used to “look” through the ice and create a seismic profile of what lies beneath the ice surface. Read on to find out how the technique works and for a special Cryosphere Christmas message! What are we doing with this ...[Read More]
Image of the Week – Understanding Antarctic Sea Ice Expansion
Sea ice is an extremely sensitive indicator of climate change. Arctic sea ice has been dubbed ‘the canary in the coal mine’, due to the observed steady decline in the summer sea ice extent in response to global warming over recent decades (see this and this previous posts). However, the story has not been mirrored at the other pole. As shown in our image of the week (blue line in Fig. 1), Antarcti ...[Read More]
Image of the Week – Searching for clues of extraterrestrial life on the Antarctic ice sheet
Last week we celebrated Antarctica Day, 50 years after the Antarctic Treaty was signed. This treaty includes an agreement to protect Antarctic ecosystems. But what if, unintentionally, this protection also covered clues of life beyond Earth? In this Image of the Week, we explore how meteorites found in Antarctica are an important piece of the puzzle in the search for extraterrestrial life. Meteori ...[Read More]