An evaluation of long-term gridded datasets of total columnar ozone retrieved from MERRA-2 and AIRS over the Indian region

• Published in: Environmental science and pollution research international 2023-03, Vol.30 (15), p.43586-43603
• Main Authors: Gupta, Priyanshu, Payra, Swagata, Bhatla, R., Verma, Sunita
• Format: Article
• Language: English
• Subjects: Air Pollutants - analysis; Air quality; Aquatic Pollution; Atmospheric Infrared Sounder; Atmospheric Protection/Air Quality Control/Air Pollution; Datasets; Earth and Environmental Science; Ecotoxicology; Emission measurements; Environment; Environmental Chemistry; Environmental Health; Environmental Monitoring - methods; Environmental science; Evaluation; Infrared analysis; Ozone; Ozone - analysis; Regression analysis; Research Article; Retrospective Studies; Seasons; Statistical analysis; Waste Water Technology; Water Management; Water Pollution Control
• ISSN: 1614-7499; 0944-1344; 1614-7499
• DOI: 10.1007/s11356-023-25319-8

Accurately determining the spatiotemporal variability of ozone on a regional to intercontinental scale is essential for air quality studies. In the present study, a first systematic evaluation and analysis of long-term (2009–2020) gridded datasets (0.5° × 0.625°) of total columnar ozone (TCO) retrieved from Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2 TCO ) is evaluated for the Indian region. The MERRA-2 TCO is first validated with observations (IMD TCO ) and then further compared with the Atmospheric Infrared Sounder (AIRS TCO ) satellite datasets. For an in-depth comparison and statistical analysis, the dataset has been segregated into seven distinct regions, i.e., Western Himalaya (WH), North East (NE), North Central (NC), North West (NW), West Peninsula India (WPI), East Peninsula India (EPI), and South Peninsula India (SPI). Descriptive statistics (NMSE, FB, R, FA2, and d) reveals a significant correlation of MERRA-2 TCO against IMD TCO for Delhi with NMSE (0.0013), FB (− 0.029) and Varanasi NMSE (0.0008), FB (− 0.014). The results of simple linear regression analysis show an increasing TCO trend value of 0.31% and 0.44% per decade in both the cities, respectively. A comparison of MERRA-2 TCO with AIRS TCO shows a significant correlation of 0.62–0.87 in different regions of India. Furthermore, in support of Brewer’s circulation pattern, an increasing shift of columnar ozone from low (SPI) to high (WH) latitudinal regions is observed. Our results show that the MERRA-2 ozone dataset can be effectively used for ozone air quality studies over India and this analysis may strengthen the need for independent, high-quality, and consistent ozone measurements with small uncertainties.