How does rising atmospheric CO2 affect marine organisms?

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Global Warming and Malaria: Does the Former Promote the Latter?
Reiter, P. 2008. Global warming and malaria: knowing the horse before hitching the cart. Malaria Journal 7: 10.1186/1475-2875-7-S1-S3.

"Man-made climate change has become a defining moral and political issue of our age," according to the author, who is with the Insects and Infectious Disease Unit of the Paris-based Institut Pasteur, and who notes that "predictions are common that in the coming decades, tens - even hundreds - of millions more cases will occur in regions where the disease is already present, and that the vectors and the pathogens will move to higher latitudes and altitudes" as the planet warms, which predictions demonize anthropogenic CO2 emissions as the ultimate cause of the "problem" so defined.

What was done
Reiter explains and reviews many complexities related to climatic effects on malaria transmission that come to bear upon these dire predictions, a subject to which he has dedicated a goodly portion of his scientific career. He begins with a consideration of mathematical models and common misconceptions, after which he focuses on malaria in temperate regions, touching on ecological change, new farm crops, new livestock rearing practices, urbanization and mechanization, human living conditions and medical care. Next comes malaria in the tropics, where he discusses stable endemic malaria, unstable endemic malaria, human birth rates, forest clearance, agriculture, movement of people, urbanization, insecticide resistance, drug resistance, degradation of health infrastructure and war and civil strife. Last of all, he addresses highland malaria in the tropics, concentrating on the Kenya and New Guinea Highlands.

What was learned
In the words of the consummate researcher, "simplistic reasoning on the future prevalence of malaria is ill-founded; malaria is not limited by climate in most temperate regions, nor in the tropics, and in nearly all cases, 'new' malaria at high altitudes is well below the maximum altitudinal limits for transmission." He further states that "future changes in climate may alter the prevalence and incidence of the disease, but obsessive emphasis on 'global warming' as a dominant parameter is indefensible [our italics], as he emphasizes that "the principal determinants are linked to ecological and societal change, politics and economics."

What it means
Although the association of enhanced malaria transmission with global warming may seem rather intuitive (which is why it is paraded by climate alarmists as a reason for curtailing anthropogenic CO2 emissions), the reality of the situation is vastly more complex, and its careful study leads to vastly different conclusions.

Reviewed 22 April 2009