Introduction

Future global environmental exposures may be significantly different from those experienced in the past. Forecasting and preparing for the resultant potential ecological, social and population health impacts requires innovative and interdisciplinary research approaches, both to advance global change/health science and to contribute to informed policy decisions. These approaches include empirical analyses and scenario-based exposure modelling to achieve meaningful risk assessments of the potential impacts of climate and ecological changes. This chapter focuses on the application of epidemiology (an empirically based discipline) to understanding the potential health consequences of global environmental change. The empirical knowledge gained from epidemiological studies should be used iteratively with model development to strengthen the foundation of predictive models.

Epidemiological research can be used in the three domains introduced in Chapter 1: first, historical analogue studies to help understand current vulnerability to climate-sensitive diseases (including contributions to understanding the mechanisms of effects) and to forecast the health effects of exposures similar to those in the analogue situation; second, studies seeking early evidence of changes in health risk indicators or health status occurring in response to actual environmental change; and third, using existing empirical knowledge and theory to develop empirical-statistical or biophysical models of future health outcomes in relation to defined scenarios of change. This chapter discusses some standard epidemiological methods used to generate quantitative estimates of exposure–disease associations for studies in these three domains. The examples focus primarily on climate variability and change to maintain consistency throughout the discussion.