Quantifying the Perturbations of Persistent Organic Pollutants Induced by Climate Change

A perturbed air-surface coupled model has been developed to simulate and predict perturbations of POPs concentrations in various environmental media under given climate change scenarios. By introducing the perturbations in air temperature and precipitation induced by climate change in the model, we have examined the corresponding perturbations in the concentration of POPs in the closed air-soil and air-water systems. Numerical experiments for several POPs have been conducted based on the possible future climate change scenarios. It was found that hexachlorobenzene (HCB), hexachlorocy-clohexanes (HCHs), and a polychlorinated biphenyl (PCBs) congener, PCB-153, exhibit strong response to specified climate change scenarios as shown by their high concentrations perturbations in air. In the air-soil system the coupled model predicts 4-50% increases in the air concentrations of these chemicals corresponding to an increase of 0.05-0.1 K yr(-1) in the air temperature. Based on our simulations, a 20% increase/decrease in precipitation can result in a 53% and 4% decrease/increase in perturbed air concentration of gamma-HCH and alpha-HCH, respectively. Also, the model can be used to determine the direction of air-surface exchange of POP perturbations induced by climate change.