In this paper, we report the first systematic comparison between dust extinction profiles forecasted by a model and measured by a Raman lidar. We use the BSC-DREAM8b model, one of the most widely used dust regional models in the Mediterranean, and Potenza EARLINET lidar profiles for Saharan dust cases, the largest one-site database of dust extinction profiles. A total of 310 dust cases were compared for the May 2000- July 2012 period. The model well reconstructs the measured layering: profiles are correlated within 5%of significance for 60%of the cases and the dust layer center of mass as measured by lidar and modeled by BSC-DREAM8b differ on average 0.3±1.0 km. Cases with a dust optical depth lower than 0.1 account for 70% of uncorrelated profiles. Although the good agreement in terms of profile shape and extinction value order of magnitude, the comparison with extinction profiles measured by the Raman lidar shows that BSC-DREAM8b typically underestimate the dust extinction coefficient in particular below 3.5 km and for low concentrations and overestimates the occurrence of dust layer top height above 15 km.
Systematic comparison of dust BSC-DREAM8b modeled profiles with Potenza EARLINET lidar database
L Mona;C Cornacchia;G Pappalardo
2013
Abstract
In this paper, we report the first systematic comparison between dust extinction profiles forecasted by a model and measured by a Raman lidar. We use the BSC-DREAM8b model, one of the most widely used dust regional models in the Mediterranean, and Potenza EARLINET lidar profiles for Saharan dust cases, the largest one-site database of dust extinction profiles. A total of 310 dust cases were compared for the May 2000- July 2012 period. The model well reconstructs the measured layering: profiles are correlated within 5%of significance for 60%of the cases and the dust layer center of mass as measured by lidar and modeled by BSC-DREAM8b differ on average 0.3±1.0 km. Cases with a dust optical depth lower than 0.1 account for 70% of uncorrelated profiles. Although the good agreement in terms of profile shape and extinction value order of magnitude, the comparison with extinction profiles measured by the Raman lidar shows that BSC-DREAM8b typically underestimate the dust extinction coefficient in particular below 3.5 km and for low concentrations and overestimates the occurrence of dust layer top height above 15 km.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.