Volcanoes under the ice: melting Antarctic ice could fight climate change

Iron is not commonly famous for its role as a micronutrient for tiny organisms dwelling in the cold waters of polar oceans. But iron feeds plankton, which in turn hold carbon dioxide in their bodies. When they die, the creatures sink to the bottom of the sea, safely storing that carbon.

Furious winds keep the McMurdo Dry Valleys in Anarctica
 free of snow and ice. Calcites found in the valleys have revealed
 the secrets of ancient subglacial volcanoes.

How exactly the iron gets to the Southern Ocean is hotly debated, but we do know that during the last ice age huge amounts of carbon were stored at the bottom of the Southern Ocean. 

Understanding how carbon comes to be stored in the depth of the oceans could help abate CO₂ in the atmosphere, and Antarctica has a powerful role.

Icebergs and atmospheric dust are believed to have been the major sources of this micronutrient in the past. However, in research published in Nature Communications, my colleagues and I examined calcite crusts from Antarctica, and found that volcanoes under its glaciers were vital in delivering iron to the ocean during the last ice age.

Read the piece on The Conversation by Associate Professor from the School of Environmental and Life Sciences  at the University of Newcastle, Silvia Frisia  - “Volcanoes under the ice: melting Antarctic ice could fight climate change.”

Southern Ocean acidifying alarmingly because of rising carbon dioxide levels

T

he Southern Ocean is acidifying at such a rate because of rising carbon dioxide emissions that large regions may be inhospitable for key organisms in the food chain to survive as soon as 2030, new US research has found.

Tiny pteropods, snail-like creatures that play an important role in the food web, will lose their ability to form shells as oceans absorb more of the CO2 from the atmosphere, a process already observed over short periods in areas close to the Antarctic coast.

Ocean acidification is often dubbed the "evil twin" of climate change. As CO2 levels rise, more of it is absorbed by seawater, resulting in a lower pH level and reduced carbonate ion concentration. Marine organisms with skeletons and shells then struggle to develop and maintain their structures.

Read Peter Hannan’s story in The Sydney Morning Herald - “Abrupt changes in food chains predicted as Southern Ocean acidifies fast: study.”