How does rising atmospheric CO2 affect marine organisms?

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Recent Increases in Arabian Sea Productivity
Reference
Goes, J.I., Thoppil, P.G., Gomes, H. do R. and Fasullo, J.T.  2005.  Warming of the Eurasian landmass is making the Arabian Sea more productive.  Science 308: 545-547.

What was done
The authors analyzed seven years (1997-2004) of satellite-derived ocean color data pertaining to the Arabian Sea, as well as associated sea surface temperatures (SSTs) and winds.

What was learned
Goes et al. report that for the region located between 52 to 57E and 5 to 10N, "the most conspicuous observation was the consistent year-by-year increase in phytoplankton biomass over the 7-year period."  So dramatic was this phenomenon, in fact, that "by the summer of 2003," in their words, "chlorophyll a concentrations were >350% higher than those observed in the summer of 1997."  They also report that the increase in chlorophyll a was "accompanied by an intensification of sea surface winds, in particular of the zonal (east-to-west) component," noting further that these "summer monsoon winds are a coupled atmosphere-land-ocean phenomenon, whose strength is significantly correlated with tropical SSTs and Eurasian snow cover anomalies on a year-to-year basis."  More specifically, they say that "reduced snow cover over Eurasia strengthens the spring and summer land-sea thermal contrast and is considered to be responsible for the stronger southwest monsoon winds."  Last of all, they state that "the influence of southwest monsoon winds on phytoplankton in the Arabian Sea is not through their impact on coastal upwelling alone but also via the ability of zonal winds to laterally advect newly upwelled nutrient-rich waters to regions away from the upwelling zone."

What it means
Goes et al.'s final conclusion is that "escalation in the intensity of summer monsoon winds, accompanied by enhanced upwelling and an increase of more than 350% in average summertime phytoplankton biomass along the coast and over 300% offshore, raises the possibility that the current warming trend of the Eurasian landmass is making the Arabian Sea more productive," which, they add, has "an immediate and important bearing on regional fisheries."

Reviewed 17 August 2005