Glacier melt adds ancient edibles to marine buffet
By Susan Trulove, Virginia Tech News, December 23, 2009 [here]
BLACKSBURG, Va., — Glaciers along the Gulf of Alaska are enriching stream and near shore marine ecosystems from a surprising source – ancient carbon contained in glacial runoff, researchers from four universities and the U.S. Forest Service report in the Dec. 24, 2009, issue of the journal “Nature.”
In spring 2008, Eran Hood, associate professor of hydrology with the Environmental Science Program at the University of Alaska Southeast, set out to measure the nutrients that reach the gulf from five glaciated watersheds …
How can a glacier be a source of the organic carbon? His curiosity peeked, in spring 2009, Hood’s Ph.D. student, Jason Fellman, collected samples from 11 watersheds along the Gulf of Alaska from Juneau to the Kenai Peninsula. The samples were analyzed to determine the age, source, and biodegradability of organic matter derived from glacier inputs. …
Hood and Scott hypothesize that forests that lived along the Gulf of Alaska between 2,500 to 7,000 years ago were covered by glaciers, and this organic matter is now coming out. “The organic matter in heavily glaciated watersheds is labile, like sugar. Microorganisms appear to be metabolizing ancient carbon and as the microorganisms die and decompose, biodegradable dissolved organic carbon is being flushed out with the glacier melt,” said Scott. … [more]
Ed Note: Forests that lived along the Gulf of Alaska between 2,500 to 7,000 years ago were subsequently covered by glaciers. The crushed organic matter is being expelled by the glaciers there today.
Again, for emphasis: 2,500 to 7,000 years ago coastal Gulf of Alaska was warm enough to grow forests. That is not the case today, since those ancient forests were subsequently engulfed by the glaciers that exist there now.
Neoglaciation has been occurring for the last 6,000+ years, ever since temperatures started to decline from the Holocene Climatic Optimum, entirely consistent with the decline in solar insolation due to Milankovitch cycles, which peaked ~10,000 years ago.
The Earth has been cooling for 6,000+ years as we head toward another Ice Age, a pattern that has been repeated ~18 times over the last 1.8 million years.
Warmer Is Better. Fight the Ice.