Effectiveness of respiratory face masks in reducing acute PM pollution exposure during peak pollution period in Delhi.

The cities of North India, such as Delhi, face a significant public health threat from severe air pollution. Between October 2021 and January 2022, 79 % of Delhi's daily average PM (Particulate matter with an aerodynamic diameter ≤ 2.5 μm) values exceeded 100 μg/m (the permissible level being 60 μg/m as per Indian standards).

Sensitivity of WRF/Chem simulated PM2.5 to initial/boundary conditions and planetary boundary layer parameterization schemes over the Indo-Gangetic Plain.

The ability of a chemical transport model to simulate accurate meteorological and chemical processes depends upon the physical parametrizations and quality of meteorological input data such as initial/boundary conditions. In this study, weather research and forecasting model coupled with chemistry (WRF-Chem) is used to test the sensitivity of PM predictions to planetary boundary layer (PBL) parameterization schemes (YSU, MYJ, MYNN, ACM2, and Boulac) and meteorological initial/boundary conditions (FNL, ERA-Interim, GDAS, and NCMRWF) over Indo-Gangetic Plain (Delhi, Punjab, Haryana, Uttar Pradesh, and Rajasthan) during the winter period (December 2017 to January 2018). The aim is to select the model configuration for simulating PM which shows the lowest errors and best agreement with the observed data.

Temporal variability of PM and its possible sources at the tropical megacity, Bengaluru, India.

The mass concentrations of PM were measured at a tropical megacity, Bengaluru, India, for the year 2015. The mean mass concentrations showed large fluctuations on day to day basis with values less than the Indian National Ambient Air Quality Standard (INAAQS) of 60 µg m. The observed annual mean mass concentration of 28 ± 11 µg m is also within the INAAQS value of 40 µg m.

Anthropogenic aerosols in precipitation over the Indo-Gangetic basin.

This study investigated the concentration of heavy metals in rainwater (RW) at a semi-arid region of the Indo-Gangetic basin to understand the influence of local, regional, or long-range transport of air pollutants during the monsoon and non-monsoonal rain. The concentration of heavy metals in RW was determined using Atomic Absorption Spectrophotometer with Graphite Furnace, the scavenging ratio was estimated, and source interpretation was carried out using Principle Component Analysis (PCA) and HYSPLIT model. Ca was the highest contributor in RW followed by Na, Fe, Mg, and Al whereas Ba, Cr, Cu, Mn, Ni, Pb, and Zn were found in trace quantity.

Analysis of Ozone Photochemistry over Southern Tropical Megacity, Bengaluru, India.

Rapid infrastructure development, increased population, shift in land use practices and higher vehicular emissions have all influenced Ozone (O ) production through its precursor gases in southern megacity, Bengaluru, India. We have investigated the photochemistry using hourly measurements of O and associated precursor gases conducted in Bengaluru during January to December 2019. The rate of formation of O is analyzed for Bengaluru for the first time using a photochemical model involving NOx cycle.