Spatio-temporal variation of aerosols in ENSO events over Western India using satellite data

Abstract

The spatial variation of the average aerosol optical depth (AOD) at 555 nm obtained from the multi-angle imaging spectroradiometer satellite sensor over India for 2000–2016 illustrates that Western India shows a relatively lower aerosol loading compared with the northern and eastern parts of India. Among the seasonal variations of the average AOD, spring shows a higher aerosol loading, particularly over Jodhpur (0.518) and Kota (0.518), and fall shows the least. In spring, these variations may be due to the meteorological conditions that bring a large quantity of dust and other types of aerosols in the atmosphere of Western India. Temporal variation of AOD indicates that in 2006, abrupt change in AOD (<0.2) was observed over all the cities. Among all cities, Mumbai shows strong increasing trends during 2000–2016 with a Sen’s slope of 0.009. Overall, the study concludes that compared with La Niña years, El Niño years correspond to a higher aerosol loading over Western India, primarily over Surat (0.357), Mumbai (0.349) and Jodhpur (0.334).