1. Introduction
Since the adoption in 1999 of the Gothenburg Protocol to abate acid- ification, eutrophication and ground-level ozone, the Government of Spain has been continuously designing and implementing regulations to abate general air pollution level and comply with its international ob- ligations as a signing party. Moreover, as a Member State of the European Union, Spain is legally-bound by the European regulatory framework on air and environmental quality which has required com- plementary policy efforts across several years. In general the policy making process for air quality control in Spain has not been a simple one, too often conditioned by conflicts between national and regional
governments in the distribution of competencies. As a result, a complete and sensible analysis of the effects of these policies not only on emis- sions or air quality levels, but on crucial variables such as human health, protection of ecosystems and associated costs has been absent for many years. In 2011, a scientific task force headed by the Centre for Integrated Assessment Modelling (CIAM) conducted a revision of the Gothenburg
Protocol using IIASA's Greenhouse gas–Air pollution Interactions and
Synergies (GAINS) model (TSAP Report #11). The results of this study revealed improvements in the general air quality picture in the Spain (as in Europe) but required establishing new reduction commitments for 2020 (Amann et al., 2012).