Ground-based assessment of Total Ozone Mapping Spectrometer (TOMS) data for dust transport over the northeastern Mediterranean

[1] Multiyear daily surface aerosol aluminum (Al) concentration and sunphotometer measurements at Erdemli (Turkey) sampling station were used to assess the performance of Absorbing Aerosol Index (AAI) and Aerosol Optical Thickness (AOT) retrieved from the daily Total Ozone Mapping Spectrometer (TOMS) over the northeastern Mediterranean. A total of 98 moderate-to-high intensity dust events with durations from 1 day to 1 week were identified by aerosol Al concentrations and/or TOMS-AAI above their threshold values of 1.0 mg m 3 and 0.5, respectively. Only 15 events were found to bring appreciable dust load into the northeastern Mediterranean, predominantly below the 850-hPa pressure level, and therefore were not detected effectively by TOMS. Eight of these events corresponded to short-range high intensity intrusions (Al > 3.0 mg m ) from nearby dust sources of the Middle East and Arabian deserts, the rest (seven events) represented moderate-to-high intensity (Al > 1.0 mg m ) long-range transport from North Africa. Given the highly complex dynamics of the region, the use of TOMS-AAI data is justified for monitoring Saharan dust transport characteristics in the northeastern Mediterranean. Moreover, the TOMS-AOT data were found to covary linearly with its counterpart obtained by the ground-based measurements (correlation coefficient 0.86, significant at <0.001), which lies within the range of estimates suggested by earlier studies.