LOOKING INTO CALIPSO CLIMATOLOGICAL PRODUCTS: EVALUATION AND SUGGESTIONS FROM EARLINET

CALIPSO (Cloud-Aerosol Lidar and Pathfinder Satellite Observations) Level 3 (CL3) data were compared against EARLINET (European Aerosol Research Lidar Network) monthly averages obtained by profiles during satellite overpasses. Data from EARLINET stations of Évora, Granada, Leipzig, Naples and Potenza, equipped with advanced multi-wavelength Raman lidars were used for this study. Owing to spatial and temporal differences, we reproduced the CL3 filtering rubric onto the CALIPSO Level 2 data. The CALIPSO monthly mean profiles following this approach are called CALIPSO Level 3*, CL3*. This offers the possibility to achieve direct comparable datasets. In respect to CL3 data, the agreement typically improved, in particular above the areas directly affected by the anthropogenic activities within the planetary boundary layer. However in most of the cases a subtle CALIPSO underestimation was observed with an average bias of 0.03 km-1. We investigated the backscatter coefficient applying the same screening criteria, where the mean relative difference in respect to the extinction comparison improved from 15.2% to 11.4%. Lastly, the typing capabilities of CALIPSO were assessed outlining the importance of the correct aerosol type (and associated lidar ratio value) assessment to the CALIPSO aerosol properties retrieval.

Annual Average Value of Solar Radiation and its Variability in Portugal

Solar resource assessment is essential for the different phases of solar energy projects, such as preliminary design engineering, financing including due diligence and, later, insurance phases. An important aspect is the long term resource estimation. This kind of estimation can only be obtained through the statistical analysis of long-term data series of solar radiation measurements, preferably ground measurements. This paper is a first step in this direction, with an initial statistical analysis performed over the radiation data from a national measurement network, consisting of eighty-nine meteorological stations. These preliminary results are presented in figures that represent the annual average values of Global Horizontal Irradiation (GHI) and its Variability in the Portuguese continental territory. These results show that the South of Portugal is the most suitable area for the implementation of medium to large scale solar plants.