The erythemal UV daily dose (EDD) and the local noon UV Index (UVI) obtained from the Ozone Monitoring Instrument (OMI), on board NASA’s Aura satellite, have been validated for the period 2005-2013 using ground based measurements at 5 different sites in the Mediterranean coast: Murcia, Valencia, Palma de Mallorca, Barcelona and Rome (where only measurements of the local noon UVI were available). Ground based measurements were made using YES UVB-1 radiometers in Murcia, Valencia, Palma de Mallorca and Barcelona, and a Brewer MKIV 067 spectrophotometer in Rome. The results of the validation showed good agreement between the satellite instrument and the ground based measurements, although the OMI values overestimate the ground based measurements, being the difference between both types of measurements maximum during the spring and summer, and minimum during autumn and winter. The evolution of the EDD shows a clear seasonal behavior for all measuring sites for both, ground based and satellite data, with maximum values in summer (June and July) and minimum values in winter (December and January). A high percentage of cases (>80%) showed minimum differences (0-1 UVI units) between the UVI obtained by OMI and the UVI obtained by ground based instruments for all measuring sites. In every measuring site, high (6-7) or very high (8-10) UVI values are reached for a high percentage of the days of the analyzed period, but very few extreme (≥11) UVI values are reached

This study analyzes the potential of very high resolution (VHR) remote sensing images and extended morphological profiles for mapping Chestnut stands on Tenerife Island (Canary Islands, Spain). Regarding their relevance for ecosystem services in the region (cultural and provisioning services) the public sector demand up-to-date information on chestnut and a simple straight-forward approach is presented in this study. We used two VHR WorldView images (March and May 2015) to cover different phenological phases. Moreover, we included spatial information in the classification process by extended morphological profiles (EMPs). Random forest is used for the classification process and we analyzed the impact of the bi-temporal information as well as of the spatial information on the classification accuracies. The detailed accuracy assessment clearly reveals the benefit of bi-temporal VHR WorldView images and spatial information, derived by EMPs, in terms of the mapping accuracy. The bi-temporal classification outperforms or at least performs equally well when compared to the classification accuracies achieved by the mono-temporal data. The inclusion of spatial information by EMPs further increases the classification accuracy by 5% and reduces the quantity and allocation disagreements on the final map. Overall the new proposed classification strategy proves useful for mapping chestnut stands in a heterogeneous and complex landscape, such as the municipality of La Orotava, Tenerife.