Some cheerful news on the climate change front today, as US government boffins report that ice breaking off the Antarctic shelves and melting in the sea causes carbon dioxide to be removed from the environment. This powerful, previously unknown “negative feedback” would seem likely to revise forecasts of future global warming significantly downwards. The US National Science Foundation (NSF) which funded the iceberg study, describes the results as having “global implications for climate research”. “These new findings… confirm that icebergs contribute yet another, previously unsuspected, dimension of physical and biological complexity to polar ecosystems,” says Roberta Marinelli, director of the NSF’s Antarctic Organisms and Ecosystems Program.
A team of NSF-funded scientists examined the effects on an area of the Weddell Sea of a large (20 mile long) berg moving through, melting as it went and diluting the salty sea water – also adding key nutrients carried from the land. They found that after the iceberg had passed, levels of CO2 had plunged and much more chlorophyll was present. Chlorophyll is the substance in green plants which lets them suck in nasty CO2 and emit precious life-giving oxygen: in the Weddell Sea it was present in phytoplankton, tiny seagoing plantoids which are thought to account for half the carbon removed from the atmosphere globally.
The scientists say that more and more icebergs are set to be found in the seas around the Anatarctic as more ice breaks off the shelves attached to the peninsula which reaches up from the polar continent towards South America. This should mean more phytoplankton and thus less CO2.
http://www.theregister.co.uk/2011/03/29/iceberg_phytoplankton_boost/
"The only thing more dangerous than ignorance is arrogance." —Albert Einstein