Understanding linkages between climate change, water quality and human health risks in the Great Lakes Region

The fourth assessment of the Intergovernmental Panel on Climate Change predicted increased threats to human and ecosystem health due to climate change (IPCC, 2007). Although the climate – hydrology nexus and potential impacts of climate change on water resources are well documented in the last several years, linkages between climate, water quality and human health are poorly understood. In particular, efforts to systematically combine future weather scenario (e.g., temperature, humidity and precipitation) with water quality and disease burden modeling are limited. Numerous studies have shown a causal relationship between gastrointestinal disease and recreational water quality as measured by indicator bacteria such as Esherichia coli and enterococci. In Michigan and other Great Lakes states, information on how climate changed in the past is available as are details of future projected changes. In this presentation, we combine this information with several modeling approaches and historical field observations of fecal indicator bacteria (FIB) in the Great Lakes region in order to tease out linkages between climate change, water quality and human health risks. We describe how this information can form the basis for disease burden modeling with emphasis on a common waterborne illness (gastroenteritis or GID) and for public health planning based on an indicator-based approach (the climate vulnerability index based on water quality CVIWQ).