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LALINET (Latin American Lidar Network) follows its goal to consolidation as a federative lidar network to provide regional coverage over Latin America in providing aerosol and greenhouse gas profiles following QA/QC protocols and promoting the development of researchers and students in atmopheric science field. We show recent results on different approaches for studying the optical properties of the atmosphere regarding aerosols at tropospheric and stratospheric level and greenhouse gas mixing ratio profiles followed by our recent support and validation efforts towards present and future satellite missions.

Soil erosion aerosols can be transported considerable distances, the Sahara is one of the major sources on the world. In June 2016 the volume scattering function of the atmospheric aerosol has been determined in the Sierra Nevada, Spain, at an altitude of 2500 m. Measurements were performed with a polar nephelometer permitting measurements between scattering angles of 5° to 175°. The values at the missing angles could be estimated to a high accuracy, using the shape of the scattering function adjacent to the missing angles, thus a complete volume scattering function was available. During the measuring period intrusions of long range transported Sahara aerosol happened several times. The classification of the aerosol was done by back trajectories and by the Angström exponent of the wavelength dependent scattering coefficient, which was determined by a three wavelength Integrating Nephelometer. The phase function of the Sahara aerosol had a stronger forward scattering, more side scattering and less backscattering compared to the usual aerosol, which is in agreement with other findings for irregular particles. The asymmetry parameter of the phase function is the best characteristic to distinguish Sahara Aerosol from non-Sahara aerosol. In this study the asymmetry parameter for the Sahara aerosol was larger than 0.65, whereas the non-Sahara aerosol had an asymmetry parameter below 0.6. A comparison with measurements performed with long range transported Gobi Desert aerosols observed in Kyoto, Japan, showed very similar results. [ABSTRACT FROM AUTHOR]

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]