Determining the desert dust aerosol presence in the Mantaro Valley, Peru

Abstract

Since March 19, 2015, a sunphotometer CIMEL CE-318T has been installed in the Huancayo Observatory, belonging to the Geophysical Institute of Peru. Aerosol Optical Depth at 440 nm (440) and the ngstrm Exponent () derived from columnar aerosol sun-photometer measurement, based on Aerosol Robotic Network (AERONET) products, has been used for aerosols classification. The used AERONET dataset correspond to quality Level 2.0. A reliable identification of desert dust events has been possible based on above mentioned parameters. A total of 5 days and 10 hours have been identified as desert dust events based on AERONET dataset and the air mass backtrajectories employing the Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT). Simulations carried out with the Weather Research and Forecasting (WRF) Model has been used to corroborate the desert dust events. The most intense event was recorded in December 27, 2016, with a maximum AOD value of 0.32 at 12:03 GMT. It has been shown that the major contribution to AOD on days identified as desert dust events, corresponds to desert dust aerosols. This is the first report for Peru, of desert dust aerosols transport from the Peruvian coastal desert to the central Andes, specifically to the Mantaro Valley.