Author(s)

A. I. Miranda, A. Monteiro, M. Lopes, C. Borrego & A. T. Perez

Abstract

Accordingly to the EU Directive 2001/81/EC, all the Member States should develop and implement a national programme to reduce the emissions of acidifying gases, in order to reach, before 2010, the National Emission Ceilings (NEC). In this context, Portugal has developed technical studies aiming to set up a reference scenario until 2010 and to evaluate the compliance of the emission ceilings established to this target year. In addition to this reference scenario, high and low emission reduction scenarios were also defined. Notwithstanding 2010 scenarios, the same procedure was applied to 2005 and two reduction scenarios, high and low, were considered. This works intends to evaluate the impacts of these national emission reduction scenarios on the air quality in Portugal, verifying the fulfilment of the air quality thresholds for 2005 and 2010. A numerical modelling system was applied over Portugal to these hypothetical situations and results were compared to those from an application to a baseline year - 2001. The selected numerical system is the 3D chemistry-transport model CHIMERE, which uses data from the European Centre for Medium Range Weather Forecast as meteorological input. Assuming the 2001 simulated meteorological conditions, the results point towards a reasonable improvement of the air quality over Portugal. It forecasted a significant decrease of ozone levels, especially in the downwind urban areas of Lisbon and Porto. These results strengthen the importance of including the NEC emission scenarios into the national strategy for air quality management. Keywords: emissions scenarios, legislation, air quality impact.

Keywords

emissions scenarios, legislation, air quality impact.