Milagro - Megacity Initiative: Local and Global Research Observations

Original image

I have been working on air quality issues in Mexico City since 2002.

The Milagro project was a great opportunity to revisit the atmosphere of the world's second largest megacity (defined by the U.N. as a city with larger 10 million inhabitants). Learn more about megacities, and their growing impact on air quality and climate here.

Check out a video on the activities during Milagro, including our spectroscopic measurements of radiation and trace-gases, and educational outreach activities.

There are presently 20 megacities globally, 15 of which are located in the developing world. 2006 presents a turning point in human history: for the first time more people were living in urban rather than rural areas on our globe. The growing trend towards urbanization is driven by the prospects for a better quality of life large city have to offer. These benefits are being offset in many cases by the negative consequences on air quality as increasing energy demands continue to be met from burning fossil fuels. As part of the MILAGRO project Mexico City served as a case study of the impacts of transboundary pollution transport from Mexico on US air quality.

My research efforts focused on the near field photochemical regime inside the greater MCMA (Mexico City Metropolitan Area). Two open-path DOAS instruments, one spectroradiometer, and a network of MAX-DOAS sensors were temporarily being deployed to Mexico City to assess the spatial distribution of pollutants, and compare ground-based observations with aircraft and satellite overflight.

The data evaluation is in progress... it is motivated from research questions arising from this selection of previous publications:

Volkamer, R.; Jimenez, J.L.; Dzepina, K.; Salcedo, D.; SanMartini, F.M.; Molina, L.T.; Worsnop, D.R.; Molina, M.J.; Secondary Organic Aerosol formation from Anthropogenic Air Pollution: Rapid and higher than expected. 2006, Geophys. Res. Lett., 33, L17811.

Lei, W.; deFoy, B.; Zavala, M.; Volkamer, R.; Molina, L.T.; Characterizing ozone production in the Mexico City Metropolitan Area: A case study using a chemical transport model. 2007, Atmos. Chem. Phys. 7, 1347-1366.

Volkamer, R.; Sheehy, P.M.; Molina, L.T.; Molina, M.J.; Oxidative capacity of the Mexico City atmosphere. Part 1: A radical source perspective. 2007, accepted for publication in Atmops. Chem. Phys. Disc.