An Example of Aerosol Pattern Variability Over Bright Surface Using High Resolution MODIS MAIAC: The Eastern and Western Areas of the Dead Sea and Environs

Lee Sever; Pinhas Alpert; Alexei Lyapustin; Yujie Wang; Alexandra Chudnovsky

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NASA NTRS · 20170007213

An Example of Aerosol Pattern Variability Over Bright Surface Using High Resolution MODIS MAIAC: The Eastern and Western Areas of the Dead Sea and Environs

Lee Sever·Pinhas Alpert·Alexei Lyapustin·Yujie Wang·Alexandra Chudnovsky

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Abstract

The extreme rate of evaporation of the Dead Sea (DS) has serious implications for the surrounding area, including atmospheric conditions. This study analyzes the aerosol properties over the western and eastern parts of the DS during the year 2013, using MAIAC (Multi-Angle Implementation of Atmospheric Correction) for MODIS, which retrieves aerosol optical depth (AOD) data at a resolution of 1km. The main goal of the study is to evaluate MAIAC over the study area and determine, for the first time, theprevailing aerosol spatial patterns. First, the MAIAC-derived AOD data was compared with data from three nearby AERONET sites (Nes Ziona - an urban site, and Sede Boker and Masada - two arid sites), and with the conventional Dark Target (DT) and Deep Blue (DB) retrievals for the same days and locations, on a monthly basis throughout 2013. For the urban site, the correlation coefficient (r) for DTDB products showed better performance than MAIAC (r = 0.80, 0.75, and 0.64 respectively) year-round. However, in the arid zones, MAIAC showed better correspondence to AERONET sites than the conventional retrievals (r = 0.58 - 0.60 and 0.48 - 0.50 respectively). We investigated the difference in AOD levels, and its variability, between the Dead Sea coasts on a seasonal basis and calculated monthlyseasonal AOD averages for presenting AOD patterns over arid zones. Thus, we demonstrated that aerosol concentrations show a strong preference for the western coast, particularly during the summer season. This preference, is most likely a result of local anthropogenic emissions combined with the typical seasonal synoptic conditions, the Mediterranean Sea breeze, and the region complex topography. Our results also indicate that a large industrial zone showed higher AOD levels compared to an adjacent reference-site, i.e., 13 percent during the winter season.

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Lee Sever, Pinhas Alpert, Alexei Lyapustin, Yujie Wang, Alexandra Chudnovsky. 2017-06-29. An Example of Aerosol Pattern Variability Over Bright Surface Using High Resolution MODIS MAIAC: The Eastern and Western Areas of the Dead Sea and Environs. https://ntrs.nasa.gov/citations/20170007213

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