SOS: Is Climate Change Suffocating Our Seas?
Posted on: Saturday, 10 October 2009, 08:36 CDT
Scientists work to explain why massive "dead zones" have been invading the Pacific Northwest's near-shore waters since 2002
Yet another ecological scourge may earn a place on the ever-lengthening list of problems potentially caused by climate change: the formation of some so-called "dead zones"—huge expanses of ocean that lose virtually all of their marine life at depth during the summer.
Possible connections between climate change and the relatively recent formation of dead zones in the Pacific Northwest's coastal waters are currently being studied by a research team that is funded by the National Science Foundation and co-led by Jack Barth of Oregon State University (OSU) and Francis Chan of OSU. (Jane Lubchenco, who is currently on leave from OSU while serving as the Administrator of the National Oceanic and Atmospheric Administration, also previously co-led the team.)
WORLDWIDE DEAD ZONES
The Earth currently has more than 400 oceanic dead zones, with the count doubling every decade. A single dead zone may cover tens of thousands of square miles.
Dead zones form where microscopic plants, known as phytoplankton, are fertilized by excess nutrients, such as fertilizers and sewage, that are generated by human activities and dumped into the ocean by rivers, or more rarely, where they are fertilized by naturally occurring nutrients. The result: blooms of organic matter that ultimately decompose through processes that rob the ocean of life-sustaining oxygen. Animals that fail to flee dead zones either suffocate or suffer severe stress.
The reference to Phytoplankton is not entirely correct - Cyanobacteria and Dinoflagalletes may lead to fall in DO level, but Diatom Algae leads to increase in DO level. They do not die and decompose, they are consumed by zooplankton or fall to the ocean floor.
This distinction is not being made by most people.
The solution is to get the right type of Phytoplankton to bloom - Diatom Algae.