Short-term impacts of air pollutants in Switzerland: model evaluations and preliminary scenario calculations for selected Swiss energy systems

摘要

In the frame of the comprehensive assessment of Swiss energy systems, air quality model simulations were performed using a 3-dimensional model (Urban Airshed Model, UAM). The aim of the study is to understand the chemical and meteorological processes so that simulations can be performed for investigating the impacts of pollutants in Switzerland for the present situation as well as for the future energy systems. As a first step, the model performance was evaluated on the basis of air quality simulations of a 3-day period in July 1993 in Switzerland. The areas where the production of photochemical pollutants are sensitive to NO_x and VOC emissions were derived. The location of these aresas were found to depend on the prevailing wind regimes. After the evaluation of the model performance, some scenario calculations were performed as follows: Base Case: simulations with the projected emissions for the year 2030, Scenario 1) all nuclear power plants were replaced by oil-driven combined cycle plants, Scenarios 2-4) traffic emissions were reduced in whole Svitzerland as well as in the cities and on the highways separately. Changes in the pollutant concentrations and depositions, and the possible short-term impacts are discussed on the basis of exceedences of critical levels for plants and limits given to protect the public health. Calculations of the long-term impacts of pollutants on ecosystems under all typical meteorological conditions encountered over the whole year are in progress.