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Friday, March 16, 2012

F. Sherwood Roland, May 2008
F. Sherwood Rowland, Nobel laureate most famous for his groundbreaking atmospheric chemistry work in the mid-nineties on the formation and destruction of the earth's ozone layer, died at his Corona del Mar home earlier this week on March 10th at the age of 84 from complications with Parkinsons Disease.

Rowland and his two colleagues Paul J. Crutzen and Mario J. Molina won the Nobel Prize in Chemistry in 1995 for their extensive work on the potential destruction of earths stratospheric ozone layer by anthropogenic sources, specifically chlorofluorocarbons (CFCs), which were commonly found in refrigerants and other man-made materials. Rowland and Molina's paper titled Stratospheric Sink for Chlorofluoromethanes: Chlorine Atom-Catalyzed Destruction of Ozone that was published in Nature in 1974, was instrumental in the banning of CFCs by the Montreal Protocol in 1996.

F. Sherwood Rowland will surely be missed and revered in the scientific community for his significant contributions.

Monday, March 12, 2012

Impact of ocean acidification on a key Arctic pelagic mollusc
As carbon dioxide (CO2) levels rise and global warming continues to rear it’s ugly head, disaster may be in store for some of our oceans key players. According to a study titled The Geological Record of Ocean Acidification published in Science this month, due to ocean acidification, the decline in pH caused by the rise of CO2 mainly due to anthropogenic sources, we may be headed into dangerous territory in comparison with historical carbon cycles.

Earth’s oceans gobble up approximately one quarter of the CO2 in the atmosphere. Carbonic acid is then formed, lowering the pH of seawater. Due to the drop in pH the concentration of the carbonate ion, which would normally be supersaturated in surface waters, is reduced. For calcifying organisms, organisms made of calcium carbonate, a decrease in carbonate ion concentrations could spell catastrophe. In the incidence that acidification directly affects calcifying organisms such as corals, molluscs and other creatures that produce their shells and plates from calcium carbonate, it could eventually upset the entire marine food chain.

In the study researchers looked to earth’s geological record for clues to what biotic responses might be based on record disruptions in carbon cycling and climate change, which were potentially caused by ocean acidification. In the past it has been challenging for researchers to determine future impacts of ocean acidification due to the limited sample period and the fact no existing oceanic crust or sediment is available for examination over 180 million years old.

Admittedly the study isn’t perfect. Researchers state in the paper “no past event perfectly parallels future projections in terms of disrupting the balance of ocean carbonate chemistry;” however, in the timespan of our geological record there are several events providing evidence regarding biotic responses in the incidence of carbon cycle disruption. It was concluded in the study that acidification levels seem to be headed for a maximum that we haven’t seen in the last 300 million years, which they call “unknown territory of marine ecosystem change.”