Luisa Molina was awarded the 2004 Volvo Environment Prize, along with her husband Mario Molina, for their collaborative work in initiating and directing the large transdisciplinary analysis which transformed understanding of the science and dynamics of air pollution in Mexico City; for their cutting edge scientific approach to programmes for the measurement of air pollutants and assessing their health effects; and for instituting policy dialogues and public outreach programmes which have led to an epoch-making approach to air-pollution management in a megacity.
Cities of all sizes are powerful generators of air pollutants that cause serious damage to all living things and that influence global climate change and stratospheric ozone depletion. At ground level, urban air pollution can also cause serious chronic harm to the health of residents. The smogs of 19th and early 20th century London and of Los Angeles in the 1960s are well known examples. This latter problem is now growing rapidly in the fast expanding towns and cities of developing countries. By the early 1990s, Mexico City had earned the title of ‘world’s most polluted city’ largely because of its rapidly growing population (now 18-20 millions) and its escalating vehicle population. Since then, however, much progress has been achieved, especially via the work initiated and directed by Luisa and Mario Molina and co-ordinated through the Massachusetts Institute of Technology’s Integrated Program on Urban, Regional and Global Air Pollution.
Their recommendations, emerging from the first phase of this skilfully integrated work, are the result of the transdisciplinary findings of over 50 researchers working in the Molina team. They used the highest quality innovative science to analyse the origins and daily patterns of emissions; to follow and predict the dynamics of how they were being transformed in the atmosphere into pollutants—using atmospheric photochemical models; to estimate the risk reduction in human mortality for a 10% clean-up in pollutants such as ozone and fine particles; and to evaluate the impacts of various emission control policies.
Most crucial was the coupling of the science with policy—the need to understand how social, economic, and political factors affect a successful control programme and the importance of involving stakeholders from the various sectors of industry and government. This first phase has clearly shown that air quality really can be improved if based on good, integrated science and a careful evaluation of options. The actual improvements, however, can only be achieved by public officials with strong commitments to the necessary action.