The right way to think about climate impacts

My last post mentioned the problems with The Atlantic's approach to climate change, which started from a set of (simplified) predictions about the future of the weather, and thus reached startlingly wrong-headed conclusions about the likely winners and losers from those changes. By contrast, the current issue of the Bulletin of the World Health Organization offers a much more useful approach, rooted in this case in an examination of climate-vulnerable public health systems, and then trying to reason as to how those systems might react (or fail to do so) to the challenge of climate change. Note in particular the way that the interaction effects between different vital systems are linked together (highlighted):

Some essential principles are already clear. A global problem requires a strategy of international dimensions that can translate into regional and local actions. Just as climate change's underlying causes are global, its health implications do not respect national boundaries. Impacts in one location, such as infectious disease epidemics or population displacements caused by droughts or rising sea levels, quickly spread across national borders. Coordinated investments in preventive measures therefore contribute to the "global public good" of reducing the risk of health emergencies. The challenge is simplified somewhat by the fact that climate change is expected to lead mainly to changes in existing health issues rather than to the emergence of new and unfamiliar diseases....

One emerging environmental health threat is the decline in global freshwater resources, caused mainly by increasing rates of water extraction and contamination. Climate change is expected to worsen this decline in water quality and quantity, particularly in already dry regions such as the eastern Mediterranean and north Africa. Scaling up water and sanitation services and providing point-of-use disinfection would reduce the current burden of disease and ameliorate the health impacts of decreasing water supplies. Such interventions already have a very high cost–benefit ratio; the threat of climate change makes these preventive health measures an even wiser investment. As water stresses intensify, governments could protect health by strengthening and enforcing their regulatory frameworks to ensure the safe use of new water sources that will become increasingly important: wastewater, excreta and greywater in agriculture and aquaculture....

Many climatic risks to health lie at least partly outside the health sector’s normal sphere of action. Perhaps most critically, climate change has the capacity to suppress agricultural yields, with the greatest risks in Africa, where malnutrition is already the largest single contributor to disease burdens. Some of the most effective actions by health professionals may therefore involve supporting other sectors’ efforts to mitigate and adapt to climate change.

It's all about the vital systems, all of which are interconnected in a series of overdetermined feedback loops.