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Maitra, Animesh
- Variation of Black Carbon Concentration Associated with Rain Events at a Tropical Urban Location
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PDF Views:113
Authors
Affiliations
1 S.K. Mitra Centre for Research in Space Environment, Institute of Radio Physics and Electronics, University of Calcutta, Kolkata 700 009, IN
1 S.K. Mitra Centre for Research in Space Environment, Institute of Radio Physics and Electronics, University of Calcutta, Kolkata 700 009, IN
Source
Current Science, Vol 107, No 1 (2014), Pagination: 72-78Abstract
Mass concentration of black carbon (BC) near the surface (within the planetary atmospheric boundary layer) was measured using a seven-channel aethalometer at Kolkata, a metropolitan city in the Indian tropical region, during the period from June 2012 to May 2013. The diurnal variation of BC concentration shows a prominent increase in the morning and evening hours, an usual feature seen over continents. However, an anomalous feature of the BC variation is observed subsequent to rain events. On normal days, the BC mass concentration during noon and early afternoon hours remains around 8000 ng/m3 at Kolkata. However, after the occurrence of isolated thundershowers, interestingly, the BC concentration increases (rather than decreasing due to washout) and at times reaches above 20,000 ng/m3 during noon and early afternoon hours. This increase is found to be associated with the formation of local temperature inversion within the atmospheric boundary layer during and after the occurrence of rain, which would suppress or inhibit vertical mixing and dispersion in contrast to non-rainy days. Results are presented to indicate the above-mentioned behaviour of BC concentration.Keywords
Black Carbon Concentration, Diurnal Variation, Rain Effect, Temperature Inversion, Tropical Urban Location.- Impacts Of Reduced Anthropogenic Activities On Black Carbon Concentration And Related Atmospheric Parameters At An Urban Metropolis Near The Land Ocean Boundary During COVID-19 Pandemic
Abstract Views :319 |
PDF Views:108
Authors
Affiliations
1 Institute of Radio Physics and Electronics, University of Calcutta, 92, Acharya Prafulla Chandra Road, Kolkata 700 009, IN
1 Institute of Radio Physics and Electronics, University of Calcutta, 92, Acharya Prafulla Chandra Road, Kolkata 700 009, IN
Source
Current Science, Vol 120, No 2 (2021), Pagination: 296-303Abstract
The ongoing COVID-19 pandemic necessitated a complete lockdown from 24 March to 31 May 2020 as imposed by the Government of India to prevent the spread of the virus that resulted into halting most of the economic activities during that period. The stringent anthropogenic activities during the lockdown phase resulted in a notable drop in the air pollution level. The prevailing global scenario during the pandemic has provided an opportunity of assessing the air quality in the absence of normal anthropogenic activities. In the present article, the impacts of reduced anthropogenic activities on the black carbon concentration and associated atmospheric parameters have been studied over a tropical urban location, Kolkata (22.57°N, 88.37°E) in eastern India. Investigations have been made on the impacts on the parameters like atmospheric electric field, wind speed, temperature, relative humidity, dew point temperature, rain accumulation and soil moisture during this unusual time in comparison to the same time span of the previous year 2019 when the usual human activities were pursued.Keywords
Atmospheric Parameters, Black Carbon, COVID-19 Lockdown, Rainfall, Soil Moisture, Wind Speed.References
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