1,720,993 research outputs found
Aerosol Measurements by Lidar in the Nocturnal Boundary Layer
No full textA lidar system capable to perform simultaneous measurements of atmospheric water vapor and aerosols have been developed in Tito Scalo, in the context of a cooperation between Universita della Baslicata and Istituo di Metodolgoie Avanzate di Analisis Ambientale. Aerosol observations by lidar in the nocturnal boundary laser (NBL) have been performed in the period 20 January- 20 February 1997, Radiosondes were launched during the measurement campaign simultaneously to lidar operation. Lidar observations have been sued to retrieve aerosol properties and dimensional characteristics. Aerosol sizes are determined by comparison measured and theoretical values of (beta) A,723(z)/(beta) A,355(z), with (beta) A,723(z) and (beta) A,355(z) being the aerosol backscattering coefficient at 723.37 and 355 nm, respectively. Furthermore, lidar and radiosonde data have been compared in order to study the NBL vertical structure and evolution. Lidar measurements of (beta) A,723(z) are compared with simultaneous radiosonde data expressed in terms of potential temperature and relative humidity, with particular emphasis on the estimate of the residual layer height from both lidar and radiosonde data. Results from the present measurements campaign will be reported and discussed in this presentation
Aerosol observations by Lidar in the Nocturnal Boundary Layer
No full textAerosol observations by lidar in the nocturnal boundary layer (NBL) were performed in Potenza, Southern Italy, from 20 January to 20 February 1997. Measurements during nine winter nights were considered, covering a variety of boundary-layer conditions. The vertical profiles of the aerosol backscattering coefficient at 355 and 723.37 nm were determined through a Klett-modified iterative procedure, assuming the extinction-to-backscattering ratio within the NBL has a constant value. Aerosol average size characteristics were retrieved from almost simultaneous profiles of the aerosol backscattering coefficient at 355 and 723.37 nm, the measurements being consistent with an accumulation mode radius not exceeding 0.4 μm. Similar results in terms of aerosol sizes were obtained from measurements of the extinction-to-backscattering ratio profile at 355 nm performed on six nights during the measurement campaign. Backscattering profiles at 723.37 nm were also converted into profiles of aerosol liquid water content
Simultaneous Application of the Raman and Dial Techniques for Ground-Based Water Vapour Lidar Measurements in the Nocturnal Boundary Layer
No full textHigh temporal and spatial resolution measurements by both space-borne and ground-based instruments are therefore necessary to monitor atmospheric water vapor for climate purposes. Lidar techniques can accomplish ground-based measurements of atmospheric water vapor with high space and time resolution. A lidar system capable to perform simultaneous measurements of atmospheric water vapor and aerosols has been developed in Potenza, Southern Italy, in the context of a cooperation between the Universita della Basilicata and Istituto di Metodologie Avanzate di Analisi Ambientale. An intensive measurement campaign was performed during 1997 in Potenza aimed to the simultaneous application of the Raman and DIAL techniques for water vapor ground- based lidar measurements. Raman and DIAL humidity measurements performed during 1997 in Potenza aimed to the simultaneous application of the Raman and DIAL techniques for water vapor ground-based lidar measurements. Raman and DIAL humidity measurements performed at night in the Planetary Boundary Layer have been compared with simultaneous radiosonde data obtained from both free and captive balloons. The agreement among Raman, DIAL and radiosonde data is found to be within 30 percent up to approximately 1.5 km. Results from this measurement campaign will be reported and discussed in this paper
CN formation and electronic excitation in a N2-CH4 atmospheric pressure dielectric barrier discharge
No full textCN(B2Σ+) formation and emission in a N2-CH4 atmospheric pressure dielectric barrier discharge
No full text
- …
