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05:45
Composition and Distribution Analysis of Bioaerosols Under Different Environmental Conditions
Published on: January 7, 2019
Precipitation and aerosol studies in India
D C Parashar1, U C Kulshrestha, M Jain
1Chemistry Division, National Physical Laboratory, New Delhi, India. parashar@csnpl.ren.nic.in
Environmental Monitoring and Assessment
|February 24, 2001
Summary
Indian rainwater is alkaline due to soil particles, but continuous rain lowers pH. Over the Indian Ocean, acidic rain suggests continental pollution transported by winds.
Area of Science:
- Atmospheric Chemistry
- Environmental Science
- Geochemistry
Background:
- Rainwater and atmospheric aerosols in India are typically alkaline, influenced by soil-derived particles rich in calcium (Ca) and magnesium (Mg).
- These alkaline components enhance the neutralization potential of rainwater, with a more significant effect observed in rural areas compared to urban settings.
- Prolonged rainfall can deplete crustal components, leading to a decrease in rainwater pH.
Purpose of the Study:
- To investigate the pH characteristics of rainwater over the Indian Ocean.
- To identify the potential causes of observed acidity in rainwater events during the Pre-campaigns of the Indian Ocean Experiment (INDOEX).
Main Methods:
- Analysis of rainwater samples collected during the Pre-campaigns of the Indian Ocean Experiment (INDOEX).
- Observation of pH levels across various rain events over the Indian Ocean.
- Correlation of atmospheric conditions and wind patterns (Northeast winds) with observed rainwater chemistry.
Main Results:
- Rainwater pH was consistently acidic across all observed events over the Indian Ocean.
- This contrasts with the typically alkaline nature of rainwater observed over the Indian continent.
- Acidic conditions are potentially linked to anthropogenic pollutants transported from the continent.
Conclusions:
- Anthropogenic emissions from the Indian continent, transported by Northeast winds, are a likely cause of acidic rainwater over the Indian Ocean.
- This highlights the transboundary impact of air pollution on oceanic environments.
- Further research is needed to quantify the contribution of specific pollutants.
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