Papers in 2021
Title:
Propagation of cloud base to higher levels during Covid-19-Lockdown
Highlights:
- Effect of polluted-to-clean conditions on cloud base height with synoptic conditions unaltered.
- Drop in pollutants continuing for a period resulted in upward shift of cloud base.
- Use of ceilometer for cloud base height and assessment of CCN.
- Significant negative correlation between cloud base height and CCN, precursor gases.
Link: https://www.sciencedirect.com/science/article/pii/S004896972037830X#!
Title:
On modelling growing menace of household emissions under COVID-19 in Indian metros
Highlights:
- Two largest megacities in India Delhi and Mumbai during the COVID-19 lockdown showed short lived decrease in CO emissions
- The biofuel emissions from residential sector remained unabated and hence the CO concentrations jumped back to the original pre – lockdown levels.
- Elevated CO levels in Delhi are due to strong winds carrying polluted air from the hot spot in central India
- In spite of lockdown, the desired results are not achieved in some pollutants unless significant policy measures are taken on sectorial priority.
Link: https://www.sciencedirect.com/science/article/pii/S0269749120366823
Papers in 2020
Title:
COVID-19 and environmental -weather markers: Unfolding baseline levels and veracity of linkages in tropical India
Highlights:
- The baseline levels of major criteria pollutants PM2.5 and NO2 have been experimentally achieved.
- This research concludes that people having exposure to higher baseline levels of particulate pollution are at greater risk of dying from COVID-19.
- The baseline levels of PM2.5 play a leading role in mortality whereas warmer temperatures show some sign in minimizing the infections.
Link: https://www.sciencedirect.com/science/article/pii/S0013935120310185
Title:
Towards baseline air pollution under COVID-19: implication for chronic health and policy research for Delhi, India
Highlights:
- Due to the COVID-19 lockdown decline in emission sources of pollutants by ~85%–90% was observed in Delhi, resulting in sharp decline in the concentration of majority of pollutants.
- The baseline level that is defined as the minimum level reached after lockdown under consistent fair weather condition of major criteria pollutants is estimated.
Link: https://search.bvsalud.org/global-literature-on-novel-coronavirus-2019-ncov/resource/en/covidwho-903132
Title:
Particulate Matter and Black Carbon in the Brahmaputra Valley of Northeast India: Observations and Model Simulation
Highlights:
- PM2.5, PM10 and BC was analyzed at Tezpur located in Brahmaputra valley and it indicated it has low local emissions, but susceptible to long range transport.
- High PM concentration is observed in winter season due to local atmospheric conditions and transport from west Asian deserts.
- Tezpur is comparatively cleaner than other north-east stations owing to its proximity to Kaziranga National Forest which aids in blocking the flow and deposition of aerosols.
- PM10 simulation by WRF-Chem is underestimated during pre-monsoon and winter season due to the low RH simulated by the model.
Link: https://link.springer.com/article/10.1007/s00024-020-02610-0
Title:
Impact of mixing layer height on air quality in winter
Highlights:
- The effect of MLH on PM2.5 and other gaseous pollutants was assessed during winter time at Delhi.
- PM2.5 and NOx varied inversely with MLH while Ozone showed positive correlation.
- Gases correlated better with MLH as compared to PM2.5 which might be indicating the ease of dispersion by the nature of respective components
- Delhi’s pollution is governed by meteorology to a large extent and hence the control measures will be more effective taking into account the meteorological conditions as well.
Link: https://www.sciencedirect.com/science/article/pii/S1364682619304262
Title:
Characteristics and Variability of Carbonaceous Aerosols over a Semi Urban Location in Garhwal Himalayas
Highlights:
- The measurements of carbonaceous aerosols at a central Himalayan semi urban location have been carried out.
- Elemental carbon and Organic carbon concentration is found to be highest during post monsoon followed by premonsoon seasons attributed to biomass burning and local anthropogenic activities.
- OC/EC ratio indicates local production of pollutants dominates over long range transport over this region.
- Boundary layer dynamics plays significant role in trapping pollutants over the region
Link: https://link.springer.com/article/10.1007%2Fs13143-019-00158-1
Title:
COVID-19 lockdown and air quality of SAFAR-India metro cities
Highlights:
- Ambient concentrations of PM2.5, PM10 and NO2 were examined in four megacities including Delhi, Ahmedabad, Mumbai and Pune of India during COVID-19 lockdown.
- Significant reductions (~60–66%) in NO2 were observed in all cities.
- Highest reduction in PM2.5 and PM10 were noticed in Delhi and Ahmedabad as against Mumbai and Pune.
- The low ratio of PM2.5/PM10 in Delhi and Ahmedabad suggests influence of wind-blown dust while relatively high ratio in Mumbai and Pune suggests dominance of secondary particles.
Link: https://www.sciencedirect.com/science/article/pii/S2212095520303291?via%3Dihub
