March 24, 2009
Disappointing Results In Climate Change Ocean Experiment
Scientists in Germany and India said an experiment to determine whether depositing hundreds of tons of dissolved iron in the Southern Ocean can diminish global warming has produced disappointing results.
In conducting the research, scientists "fertilized" a 115 square mile area of ocean by placing six tons of dissolved iron inside the core of an eddy -- a large, rotating column of water.
The researchers hoped the iron would stimulate the growth of tiny planktonic algae known as phytoplankton, which would in turn take up carbon dioxide out of the atmosphere.
As expected, the iron succeeded in triggering the growth of the phytoplankton, however they were then eaten by tiny crustacean zooplankton.
The researchers from India's National Institute of Oceanography (NIO) and Germany's Alfred Wegener Institute (AWI) said the results had "dampened hopes" that their approach would be an effective weapon in combating global climate change.
"The cooperative project Lohafex has yielded new insights on how ocean ecosystems function," the AWI said in a statement published on Monday.
"But it has dampened hopes on the potential of the Southern Ocean to sequester significant amounts of carbon dioxide (CO2) and thus mitigate global warming."
Previous initiatives using iron fertilization had proved more successful since they used algae protected by hard shells. However, these types of algae do not thrive in the Southern Ocean, the institute said.
The scientists left Cape Town on January 7 and spent nearly three months conducting the experiments, surrounded by the treacherous waves of the infamous "Roaring Forties." Twice they were forced to escape approaching storms.
Nevertheless, the AWI called the adventure an "exciting experience laced with the spirit of adventure and haunted by uncertainty quite unlike other scientific cruises."
The experiment is one of several prospective geo-engineering solutions that have been receiving more serious attention in recent years as political progress to combat greenhouse gas emissions hits various stumbling blocks.
However, environmentalists heavily criticize such geo-engineering schemes for failing to address the human behavior they say is responsible for global warming, and for having potentially unintended and devastating consequences.
Other geo-engineering approaches include sowing sulphur particles in the atmosphere to reflect solar radiation and installing mirrors in orbit to deflect sunlight.
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