Current Research focus:
Research is pursued in four broad inter related areas of environmental science, namely
Atmospheric OH Radical Chemistry
Ozone and Aerosol Chemistry
Volatile Organic Compounds (VOCs) : Emissions and Impacts
Ambient Air Quality of Mega Cities
The main analytical techniques used by the group are:
Proton transfer reaction mass spectrometry (PTR-MS)
Optical spectroscopic methods (UV, Chemiluminescence & IR)
10,000 to 100,000 different organic compounds have been measured in the Earth's atmosphere (total emission estimate ˜ 1.3 billion tonnes of carbon). In combination with NOx and sunlight these emissions fuel the formation of tropospheric ozone which is a major health and agricultural hazard when present at high levels.
Chemical conversion by the "detergent" of the atmosphere, namely the OH radical converts emissions into more easily removable secondary products (e.g. Secondary organic aerosol (SOA) and oxygenated VOCs), which also significantly influence the chemical composition of the atmosphere, in turn affecting the radiative balance (climate), activity of cloud condensation nuclei (CCN) and atmospheric dynamics with widespread health and climate impacts. Our group investigates these chemical processes in order to develop basic scientific understanding required for assessing pollution impacts and proposing mitigation strategies and policies.
- Kumar, V., Sinha, V., VOC-OHM: A new technique for rapid measurements of ambient total OH reactivity and volatile organic compounds using a single proton transfer reaction mass spectrometer, Int. J. Mass Spectrom., http://dx.doi.org/10.1016/j.ijms.2014.10.012, 2014.
- Sinha,V., Kumar,V., and Sarkar,C.: Chemical composition of pre-monsoon air in the Indo-Gangetic Plain measured using a new PTR-MS and air quality facility: high surface ozone and strong influence of biomass burning, Atmos. Chem. Phys., 14, 5921-5941, 2014.
- Sarkar C., Kumar, V., Sinha, V: Massive emissions of carcinogenic benzenoids from paddy residue burning in North India, Current Science, Volume 104 (12) , pp. 1703-1709, 2013.
- Sinha, V., Williams, J., Lelieveld, J., Ruuskanen, T., Kajos, M., Patokoski, J., Hellen, H., Hakola, H, Morgensen, D., Boy, M., Rinne, J., Kulmala, M., OH reactivity measurements within a boreal forest: Evidence for unknown reactive emissions, Environmental Science and Technology, doi: 10.1021/es101780b, 2010.
- Sinha, V., Williams, J., Crowley, J., Lelieveld J., The Comparative Reactivity Method : A new tool to measure the total OH Reactivity of ambient air: Atmos. Chem. Phys., 8, 2213-2227,2008.