This week a major new study revealed Greenland’s melting ice sheet will likely contribute almost a foot to global sea level rise by the end of the century — that’s twice as much as previously reported. Writing in the journal Nature Climate Change, researchers found that even if the world were to halt all greenhouse gas emissions today, higher levels of atmospheric carbon dioxide have already doomed 120 trillion tons of Greenland’s ice to melt. Without urgent action to mitigate the damage, researchers warn, sea level rise could be far higher.
“zombie” is a good term. What we found is that the Greenland ice sheet is trying to recover from damage that we’ve already done. So we’re not even talking about future climate change. This foot of sea level rise is due to the damage we have already caused. And in order to kind of correct this damage, the ice sheet is trying to shrink and readjust its position, and this is leaving ice along the margins of the ice sheet essentially dynamically disconnected from the rest of the ice sheet. It’s dead ice. It’s already committed to the oceans. And that’s why we’re calling it “zombie ice.” It’s relegated to the oceans and to sea level rise, and there’s nothing that we can do about that now. Our best hope is just try to prepare for the future and try not to make it worse.
— source democracynow.org | Sep 01, 2022
Algae that live on snow and ice produce a kaleidoscope of colours. Jason Edwards/NGC
Researchers are fanning out across the Greenland ice sheet this month to explore a crucial, but overlooked, influence on its future: red, green and brown-coloured algal blooms. These darken the snow and ice, causing it to absorb more sunlight and melt faster. The Black and Bloom project aims to measure how algae are changing how much sunlight Greenland’s ice sheet bounces back into space. The algae creates vast, colourful fields of what is popularly known as ‘watermelon snow’. 6 types of algae living at 40 red-snow sites in Norway, Sweden, Greenland and Iceland. By comparing the optical properties of red snow to clean snow, researchers estimated that algal blooms could reduce reflectivity by 13% over the melting season.
— source nature.com | 2016
meltwater funnels rock dust into Greenland’s glacial rivers, where Jon Hawkings and his colleagues took their samples. They found that Greenland’s rivers are much richer in phosphorus than previously believed. And they estimate that Greenland’s glacial rivers may flush some 400,000 tons of phosphorus into ocean waters every year—that’s on par with the amount of phosphorous dumped into the ocean by the Mississippi or Amazon rivers. The findings appear in the journal Global Biogeochemical Cycles.
— source scientificamerican.com
Holes that carry surface meltwater to the base of the Greenland ice sheet, called moulins, are much larger than previously thought, according to a new study based on observation and first-hand exploration by a team including a geologist from the University of Arkansas. The extra volume could influence the stability of the Greenland ice sheet and how quickly it slides toward the sea.
— source University of Arkansas | Nov 17, 2020
An international team of researchers led by the University of Bristol camped for three months next to the Greenland Ice Sheet, sampling the meltwater that runs off a large catchment (> 600 km2) of the Ice Sheet during the summer months. As reported in Nature, using novel sensors to measure methane in meltwater runoff in real time, they observed that methane was continuously exported from beneath the ice. They calculated that at least six tons of methane was transported to their measuring site from this portion of the Ice Sheet alone. Methane gas (CH4) is the third most important greenhouse gas in the atmosphere after water vapour and carbon dioxide (CO2). Although, present in lower concentrations that CO2, methane is approximately 20-28 times more potent.
— source University of Bristol | Jan 3, 2019