Characteristics of atmospheric boundary layer structure using monostatic SODAR system over Mumbai region

Atmospheric Boundary Layer (ABL) height variability, along with meteorological parameters and pollutant concentrations, are studied during different months in Mumbai region for the period of November 2020 to October 2021. ABL height is measured using a monostatic SODAR (SOnic Detection And Ranging) system. The capabilities, behaviour, and benefits of employing this ground-based remote sensing system in Mumbai are examined in this preliminary report after a year of SODAR monitoring. SODAR dataset is also compared with Radiosonde input ERA5 reanalysis data. The ventilation coefficient (VC) analysis for the same time period is also covered in the paper. Especially in the months of November, December, January, February, August, September, and October, the ABL height often approached 700 m. The ABL height is increased to 1000–1200 m in April because of the strong winds and warm weather. The month of April has the greatest monthly average height (418 m), while the month of February has the lowest monthly average height (179 m). In April, when the wind speed is 7.2 m/s, the convection duration is observed to be the longest, while in December, when the wind speed is 1.75 m/s, it is the shortest. Research highlights For the first time, real-time hourly atmospheric boundary layer height data measured from SODAR system are analysed over the Mumbai region. The ABL height often reached 700 m, especially in the months of November, December, January, February, August, September, and October. Due to the high wind and warmth in April, the ABL height is extended to 1000–1200 m. The highest ventilation coefficient values around 7095 m 2 /s are recorded in the month of April, while the lowest values around 2912 m 2 /s are recorded in the months of November and December.