| Autor: |
Bravo-Aranda, Juan Antonio, de Arruda Moreira, Gregori, Navas-Guzmán, Francisco, Granados-Muñoz, María José, Guerrero-Rascado, Juan Luis, Pozo-Vázquez, David, Arbizu-Barrena, Clara, Reyes, Francisco José Olmo, Mallet, Marc, Arboledas, Lucas Alados |
| Předmět: |
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| Zdroj: |
Atmospheric Chemistry & Physics; 2017, Vol. 17 Issue 11, p6839-6851, 13p, 1 Diagram, 1 Chart, 4 Graphs, 2 Maps |
| Abstrakt: |
The automatic and non-supervised detection of the planetary boundary layer height (zPBL/by means of lidar measurements was widely investigated during the last several years. Despite considerable advances, the experimental detection still presents difficulties such as advected aerosol layers coupled to the planetary boundary layer (PBL) which usually produces an overestimation of the zPBL. To improve the detection of the zPBL in these complex atmospheric situations, we present a new algorithm, called POLARIS (PBL height estimation based on lidar depolarisation). POLARIS applies the wavelet covariance transform (WCT) to the range-corrected signal (RCS) and to the perpendicularto- parallel signal ratio profiles. Different candidates for zPBL are chosen and the selection is done based on the WCT applied to the RCS and. We use two ChArMEx (Chemistry-Aerosol Mediterranean Experiment) campaigns with lidar and microwave radiometer (MWR) measurements, conducted in 2012 and 2013, for the POLARIS' adjustment and validation. POLARIS improves the zPBL detection compared to previous methods based on lidar measurements, especially when an aerosol layer is coupled to the PBL. We also compare the zPBL provided by the Weather Research and Forecasting (WRF) numerical weather prediction (NWP) model with respect to the zPBL determined with POLARIS and the MWR under Saharan dust events. WRF underestimates the zPBL during daytime but agrees with the MWR during night-time. The zPBL provided by WRF shows a better temporal evolution compared to theMWRduring daytime than during night-time. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
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