[1] This study analyzes tide transformation in the Guadalquivir estuary (SW Spain). When fresh water discharges are less than 40 m 3 /s, the estuary is tidally-dominated (flood-dominated) and well mixed. Under such conditions, the estuary can be divided into three stretches, each characterized by a different tide propagation process. In the first stretch of 25 km, the dominant process is diffusion. In the next stretch, approximately over 35 km length, convergence and friction processes are in balance. At the head of the estuary, in the last stretch, the tidal motion is partially standing because of tidal reflection on the Alcalá del Río dam, located 110 km upstream from the estuary mouth. The reflection coefficient R varies with the frequency; for diurnal constituents its magnitude |R D | is 0.25; this value increases in the case of semi-diurnal (|R S | ≈ 0.40), and quarter-diurnal constituents (|R Q | ≈ 0.65), and reaches its minimum at the sixth-diurnal components (|R X | ≈ 0.10). The tidal reflection can generate residual currents that have consequences in the bed morphology. Furthermore, when the fresh water discharges are greater than 400 m 3 /s, the estuary is fluvially-dominated and the water level can be calculated as the linear superposition of tide and river contributions. However, superposition arguments do not hold for currents at any point in the estuary.

A forest fire started on August 8 th , 2016 in several places on Madeira Island causing damage and casualties. As of August 10 th the local media had reported the death of three people, over 200 people injured, over 950 habitants evacuated, and 50 houses damaged. This study presents the preliminary results of the assessment of several spectral indices to evaluate the burn severity of Madeira fires during August 2016. These spectral indices were calculated using the new European satellite Sentinel-2A launched in June 2015. The study confirmed the advantages of several spectral indices such as Normalized Difference Vegetation Index (NDVI), Green Normalized Difference Vegetation Index (GNDVI), Normalized Burn Ratio (NBR) and Normalized Difference Vegetation Index (NDVIreXn) using red-edge spectral bands to assess the post-fire conditions. Results showed high correlation between NDVI, GNDVI, NBR and NDVIre1n spectral indices and the analysis performed by Copernicus Emergency Management Service (EMSR175), considered as the reference truth. Regarding the rededge spectral indices, the NDVIre1n (using band B5, 705nm) presented better results compared with B6 (740 nm) and B7 (783 nm) bands. These preliminary results allow us to assume that Sentinel-2 will be a valuable tool for post-fire monitoring. In the future, the two twin Sentinel-2 satellites will offer global coverage of the Madeira Archipelago every five days, therefore allowing the simultaneous study of the evolution of the burnt area and reforestation information with high spatial (up to 10 m) and temporal resolution (5 days).

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