How does rising atmospheric CO2 affect marine organisms?

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The Winds of Climate Change: Altering Albatross Life-History Traits
Weimerskirch, H., Louzao, M. de Grissac, S. and Delord, K. 2012. Changes in wind pattern alter albatross distribution and life-history traits. Science 335: 211-214.

The authors write that "in marine systems, wind is a major component of the environment, and climate change-induced alterations in oceanic wind regimes and strength have already occurred and are predicted to increase." With respect to what has "already occurred," they note that "over the past fifty years, Southern Hemisphere westerlies have shifted poleward and increased in intensity," which could well affect "the movement or distribution of wind-dependent species, such as migratory land birds or pelagic seabirds," the latter of which "rely extensively on wind to move at low costs between breeding and foraging sites," citing the studies of Weimerskirch et al. (2000) and Wakefield et al. (2009).

What was done
Weimerskirch et al. (2012) studied the effects of documented changes in wind conditions over the Southern Ocean on the foraging ecology and life-history traits of the wandering albatross (Diomedea exulans, one of the most wide-ranging pelagic seabirds), employing data on (1) the duration of their foraging trips and breeding success that were collected over the period 1966-2010, as well as (2) foraging performance and body mass that were collected over the period 1989-2010, focusing on breeding birds from the Crozet Islands, which are situated in the windiest area of the Southern Ocean.

What was learned
The four researchers report that over the period of time characterized by the IPCC as having experienced unprecedented global warming, the foraging range of wandering albatrosses has shifted poleward, as the meridional component of the wind has also "strongly increased and shifted poleward." And as a result of this change in wind velocity, they found that albatross "rates of travel and flight speeds have increased," a trend that they say has also been found to have occurred in the southwestern Indian Ocean over the past thirty years by Peron et al. (2010).

One extremely important consequence of this change was a 22% decrease in the duration of albatross foraging trips between 1970 and 2008 (a drop from 12.4 to 9.7 days). And as a consequence of this change, they write that "breeding success has improved, and birds have increased in mass by more than one kilogram," which equates to a 10-12% increase in body weight for males and females alike.

What it means
The above-described real-world climate changes of the past half-century, in the words of Weimerskirch et al. (2012), "have affected positively the foraging efficiency and foraging range of wandering albatrosses, ultimately improving breeding success and reducing mortality risks, respectively." And we estimate from their graph of the pertinent data, that albatross breeding success rose from approximately 65% to 77% over the period they studied, courtesy of the catastrophically dreadful phenomenon of CO2-induced global warming. How sweet it really is!

Peron, C., Authier, M., Barbraud, C., Delord, K., Besson, D. and Weimerskirch, H. 2010. Interdecadal changes in at-sea distribution and abundance of sub-antarctic seabirds along a latitudinal gradient in the Southern Indian Ocean. Global Change Biology 16: 1895-1909.

Wakefield, E., Phillips, R.A., Matthiopoulos, J., Fukuda, A., Higuchi, H., Marshall, G.J. and Trathan, P.N. 2009. Wind field and sex constrain the flight speeds of central-place foraging albatrosses. Ecological Monographs 79: 663-679.

Weimerskirch, H., Guionnet, T., Martin, J., Shaffer, S.A. and Costa, D.P. 2000. Fast and fuel efficient? Optimal use of wind by flying albatrosses. Proceedings of the Royal Society B 267: 1869-1874.

Reviewed 6 June 2012