Recently there is a growing interest in the study of aerosol compounds in the troposphere because of their influence in many atmospheric processes. The monitoring of aerosol particles in the atmosphere can be realised in real time with lidar systems using optical backscattering for the study of atmospheric properties. Furthermore, lidar technique is becoming a powerful tool for study the aerosols optical properties in urban area giving time-dependent aerosols mapping of the urban atmosphere. A field measurements campaign aimed to study comparatively the PBL structure and evolution in two sites differing for orography and urbanization level has been worked out in Southern Italy by applying the lidar technique. The two sites (Naples and Pontecagnano) are located 50 km apart on the Tyrrhenian coast. Naples (40°50'N-14°10'E, 118m a.s.l.) is an urban area with a very high level of urbanization and a huge aerosol content located mainly below the PBL. Pontecagnano (40°37'N-14°53'E) is a rural and flat area. The effect of the orography and the closeness of the sea influence the local circulation phenomena related to diurnal changes in surface temperature and the PBL evolution and affect the aerosol vertical distribution. Using aerosols as tracers, the lidar technique has been applied in order to follow the evolution of the Planetary Boundary Layer in both sites during a complete diurnal cycle. Futhermore, airborne atmospheric measurements of mass, momentum, and energy fluxes of boundary layer research have been available by the use of a Sky Arrow 650 Environmental Research Aircraft (ERA) flying over Pontecagnano. A study of correlations between PBL height and the temperature measured at ground level in Naples and sensible heat in Pontecagnano has been performed by evaluating the correlation coefficient between these parameters as a function of the relative delay. We found the maximum correlation for a delay of about 100 min in Naples and of about 180 min in Pontecagnano. This difference in the response of PBL to the heat flux from the surface to atmosphere is due to the different kind of use of soil.
Study of Planetary Boundary Layer evolution in urban/rural sites in Southern Italy
2007
Abstract
Recently there is a growing interest in the study of aerosol compounds in the troposphere because of their influence in many atmospheric processes. The monitoring of aerosol particles in the atmosphere can be realised in real time with lidar systems using optical backscattering for the study of atmospheric properties. Furthermore, lidar technique is becoming a powerful tool for study the aerosols optical properties in urban area giving time-dependent aerosols mapping of the urban atmosphere. A field measurements campaign aimed to study comparatively the PBL structure and evolution in two sites differing for orography and urbanization level has been worked out in Southern Italy by applying the lidar technique. The two sites (Naples and Pontecagnano) are located 50 km apart on the Tyrrhenian coast. Naples (40°50'N-14°10'E, 118m a.s.l.) is an urban area with a very high level of urbanization and a huge aerosol content located mainly below the PBL. Pontecagnano (40°37'N-14°53'E) is a rural and flat area. The effect of the orography and the closeness of the sea influence the local circulation phenomena related to diurnal changes in surface temperature and the PBL evolution and affect the aerosol vertical distribution. Using aerosols as tracers, the lidar technique has been applied in order to follow the evolution of the Planetary Boundary Layer in both sites during a complete diurnal cycle. Futhermore, airborne atmospheric measurements of mass, momentum, and energy fluxes of boundary layer research have been available by the use of a Sky Arrow 650 Environmental Research Aircraft (ERA) flying over Pontecagnano. A study of correlations between PBL height and the temperature measured at ground level in Naples and sensible heat in Pontecagnano has been performed by evaluating the correlation coefficient between these parameters as a function of the relative delay. We found the maximum correlation for a delay of about 100 min in Naples and of about 180 min in Pontecagnano. This difference in the response of PBL to the heat flux from the surface to atmosphere is due to the different kind of use of soil.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
