Suchergebnisse

Attenuated backscatter measurements from a Vaisala CL31 ceilometer and a modified form of the well-known slope method are used to derive the ceilometer extinction profiles during rain events, restricted to rainfall rates (RRs) below approximately 10 mm/h. RR estimates from collocated S-band radar and portable disdrometer are used to derive the RR-to-extinction correlation models for the ceilometer-radar and ceilometer-disdrometer combinations. Data were collected during an intensive observation period of the Verification of the Origins of Rotation in Tornadoes Experiment Southeast (VORTEX-SE) conducted in northern Alabama. These models are used to estimate the RR from the ceilometer observations in similar situations that do not have collocated radar or the disdrometer. Such correlation models are, however, limited by the different temporal and spatial resolutions of the measured variables, measurement capabilities of the instruments, and the inherent assumption of a homogeneous atmosphere. An empirical method based on extinction and RR uncertainty scoring and covariance fitting are proposed to solve, in part, these limitations. ; This work was supported by the National Oceanic and Atmospheric Administration (NOAA) under Grant NA1501R4590232 and Grant NA16OAR4590209 and by the Department of Earth, Atmospheric, and Planetary Sciences, Purdue University. CommSensLab-Universitat Politècnica de Catalunya (UPC) (which is a María de Maeztu Excellence Unit funded by the Agencia Estatal de Investigación, Spain; MDM-2016-0600) collaborated via Spanish Government - European Regional Development Funds under PGC2018-094132-B-I00 and TEC2015- 63832-P projects, and via European Union (funds) (EU) Funds under Grant H2020 ACTRIS-2 (GA-654109) and Grant ACTRIS-PPP (GA-739530). The work of Rubén Barragán was supported by the Spanish Ministry of Science, Innovation and Universities under Grant BES-2013-066340. ; Peer Reviewed ; Postprint (published version)