Evidence against Rapid Mercury Oxidation in Photochemical Smog.

Mercury pollution is primarily emitted to the atmosphere, and atmospheric transport and chemical processes determine its fate in the environment, but scientific understanding of atmospheric mercury chemistry is clouded in uncertainty. Mercury oxidation by atomic bromine in the Arctic and the upper atmosphere is well established, but less is understood about oxidation pathways in conditions of anthropogenic photochemical smog. Many have observed rapid increases in oxidized mercury under polluted conditions, but it has not been clearly demonstrated that these increases are the result of local mercury oxidation.

Outdoor air pollution in India is not only an urban problem.

Urban outdoor air pollution in the developing world, mostly due to particulate matter with diameters smaller than 2.5 µm (PM), has been highlighted in recent years. It leads to millions of premature deaths.

Premature Mortality Due to PM Over India: Effect of Atmospheric Transport and Anthropogenic Emissions.

The annual premature mortality in India attributed to exposure to ambient particulate matter (PM) exceeds 1 million (Cohen et al., 2017, https://doi.org/10.

Aerosol Optical Depth Over India.

Tropospheric aerosol optical depth (AOD) over India was simulated by Goddard Earth Observing System (GEOS)-Chem, a global 3-D chemical-transport model, using SMOG (Speciated Multi-pOllutant Generator from Indian Institute of Technology Bombay) and GEOS-Chem (GC) (current inventories used in the GEOS-Chem model) inventories for 2012. The simulated AODs were ~80% (SMOG) and 60% (GC) of those measured by the satellites (Moderate Resolution Imaging Spectroradiometer and Multi-angle Imaging SpectroRadiometer). There is no strong seasonal variation in AOD over India.

Decadal changes in surface ozone at the tropical station Thiruvananthapuram (8.542° N, 76.858° E), India: effects of anthropogenic activities and meteorological variability.

This paper presents the first observational results from an Indian station on the long-term changes in surface ozone (O)-a major environmental pollutant and green house gas-over a period of about 40 years. It is based on the in situ measurements carried out during 1973-1975, 1983-1985, 1997-1998 and 2004-2014 at the tropical coastal station, Thiruvananthapuram. From 1973 to 1997, surface O shows a slow increase of ~ 0.