I’m off to the snow soon for the winter school holiday.
A few days of skiing and sledging. A few years ago, I rediscovered sledging actually, who knew that this could be so much fun! Not just for the kids but adults too. There are even sledging slopes.
So, this Friday Find will be a wintry one.❄️
🧊Ice sheets
👉Ice sheets aren’t just massive blocks of ice. They host micro-ecosystems! Microorganisms live on, near the surface and even within ice. And old ice hosts ancient microorganisms, which holds key information about life over the ages
👉But among these microorganisms in the ice are photosynthetic bacteria that release carbon (because they don’t use oxygen). When the ice melts these bacteria become more active = more carbon
👉Icebergs help to store carbon. How? Icebergs floating around increase phytoplankton activity. These microalgae sequester a huge amount of carbon. When they die, they sink to the seabed (with the carbon)
Melting ice
👉Ice sheets obviously hold a huge amount of frozen fresh water (not salty)
👉What happens when ice melts too quickly? Changes in water salinity, in water temperature, in water density and in water circulation
👉All the changes have an impact on the natural evaporation cycle of water, which changes the air temperature and humidity = deregulates climate
👉Ice-melt runoff is a natural and necessary process to feed water into rivers. But when ice is melting at a fast pace it creates floods and landslides
Did you know?
💡If the Greenland ice sheet melted, the global sea level would rise by 7.4 metres!
💡A frozen sea loses its salt content over time
Snow on ice
👉Thick ice that is covered in snow reflects sunlight back out into the atmosphere. This slows the ice from melting
👉There is more thin ice right now that doesn’t necessarily survive a summer, and is more vulnerable. Plus, it doesn’t have the snow on top of it to reflect sunlight
💡Solutions to stop ice-sheets from melting
-Solutions to slow ice melting have been underway for some time, including initiatives by the Arctic Ice Project to create a substance that reflects sunlight to mimic snow on thick ice (but this initiative is now shutting down)
-’Water curtains’ is a new idea to protect ice sheets from warm-water inflow, which melts the ice sheets from underneath
-A start-up in Greenland is working on ways to capture melting ice there to combat water shortages elsewhere in the world. There are pros and cons to this project, but it’s true that there is plenty of melting ice…
-Recently ‘giant’ viruses have been discovered on Greenland’s ice sheet that can be important to get rid of a type of algae that makes ice dark and causes it to melt.
🙌Interesting ideas, but as other scientists say, let’s focus on reducing greenhouse emissions, because the Arctic/Antarctic projects are expensive and difficult to implement.
(Sources: National Snow and Ice Data Center, ASM, MPI, Nature, Earth Magazine, The Guardian, UNESCO, Wired, The Week, BioTechniques, Arctic Ice Project)