How does rising atmospheric CO2 affect marine organisms?

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Phytoplankton of the Southern Ocean: 1965-2002
Hirawake, T., Odate, T. and Fukuchi, M.  2005.  Long-term variation of surface phytoplankton chlorophyll a in the Southern Ocean during 1965-2002.  Geophysical Research Letters 32: 10.1029/2004GL021394.

What was done
The authors analyzed chlorophyll a data obtained from Japanese Antarctic Research Expedition cruises made by the Fuji and Shirase ice-breakers between Tokyo and Antarctica from 15 November to 28 December of nearly every year between 1965 and 2002 in a study of interannual variations of phytoplankton biomass, calculating results for the equatorial region between 10N and 10S, the Subtropical Front (STF) region between 35S and 45S, and the Polar Front (PF) region between 45S and 55S.

What was learned
Hirawake et al. report that an increase in chl a was "recognized in the waters around the STF and the PF, especially after 1980 around the PF in particular," and that "in the period between 1994 and 1998, the chl a in the three regions exhibited rapid gain simultaneously."  They also say "there were significant correlations between chl a and year through all of the period of observation around the STF and PF, and the rates of increase are 0.005 and 0.012 mg chl a m-3 y-1, respectively."  In addition, they report that the satellite data of Gregg and Conkright (2002) "almost coincide with our results."

What it means
The Japanese scientists say that "simply considering the significant increase in the chl a in the Southern Ocean, a rise in the primary production as a result of the phytoplankton increase in this area is also expected."  It is most interesting, therefore, that over the period of time during which climate alarmists lamented the warming of the world that they continue to say was so unprecedented and damaging to the biosphere, aquatic productivity in the Southern Ocean bucked their gloom-and-doom scenario and forged ahead to ever greater levels of carbon fixation and growth.  Yet that is just what one should expect when atmospheric CO2 concentrations and temperature rise hand-in-hand in concert with each other (see Cowling and Sykes, 1999; Taub et al., 2000; and our Editorial of 15 Oct 1999).

Cowling, S.A. and Sykes, M.T.  1999.  Physiological significance of low atmospheric CO2 for plant-climate interactions.  Quaternary Research 52: 237-242.

Gregg, W.W. and Conkright, M.E.  2002.  Decadal changes in global ocean chlorophyll.  Geophysical Research Letters 29: 10.1029/2002GL014689.

Taub, D.R., Seeman, J.R. and Coleman, J.S.  2000.  Growth in elevated CO2 protects photosynthesis against high-temperature damage.  Plant, Cell and Environment 23: 649-656.

Reviewed 27 April 2005