Roundup: Hot Rocks, Dissolved Organic Matter, and Dry-Snow Densification

Elevated Geothermal Surface Heat Flow

From Earth and Planetary Science Letters: “This study provides ground-truth for regional indirect GHF [Geothermal Heat Flow] estimates in the Amundsen Sea Embayment, which is part of the West Antarctic Rift System, by presenting in situ temperature measurements in continental shelf sediments. Our results show regionally elevated and heterogeneous GHF (mean of 65 mWm-2) in the Amundsen Sea Embayment.

Read the research paper here.

Glaciers seen during NASA’s Operation IceBridge research flight to West Antarctica on Oct. 29, 2014 (Source: NASA/Michael Studinger).

 

Dissolved Organic Matter in an Arctic Fjord

From Limnology and Oceanography: “Arctic waters are often enriched with terrestrial dissolved organic matter (DOM) characterized by having elevated visible wavelength fluorescence (commonly termed humic-like). Here, we have identified the sources of fluorescent DOM (FDOM) in a high Arctic fjord (Young Sound, NE Greenland) influenced by glacial meltwater.”

Read more about the dissolved organic matter here.

Fohn Fjord in Greenland (Source:Flickr/Rita Willaert).

 

Modeling Dry-Snow Densification

From Geosciences“In the accumulation areas of ice sheets, ice caps, and glaciers, snow is deposited on the surface and, with time, becomes denser until it turns into ice. This process of densification proceeds at a rate that depends on climatic conditions; slowly in the cold, desert regions in the interior of the great polar ice sheets, and more rapidly in warmer regions with higher precipitation. The question of how to calculate this rate from given climatic information is an important aspect of many areas of glaciological research.”

Read more about the microscopic processes by which snow turns into ice on glaciers here.

A large iceberg had recently separated from the calving front of Antarctica’s Pine Island Glacier 2013 (Source: Flickr/U.S. Geological Survey).