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Time lapses of moisture index and concentration of chlorophyll a in the Guadiana River

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Time lapses of moisture index and chlorophyll a

Title: Time lapses of moisture index and concentration of chlorophyll a in the Guadiana River

Description: These images feature screenshots of two time lapses of normalised difference moisture index (NDMI, left panel) and Chlorophyll a (right panel) maps of the Alqueva Reservoir and a section of the Guadiana River, in Alentejo, Portugal. Both images were generated in the EO-Browser web-platform for cloud-computing, using L2A Copernicus Sentinel-2 products.

The background of the map on the right is generated using SWIR bands of Copernicus Sentinel-2 to highlight the land use and land cover: bare soil represented in brown and vegetation in green. Negative values of NDMI are associated to water stress or barren soil. Moisture content increases as the values become positive and higher. Comparing the distribution of NDMI with that of chlorophyll a over the years, provides valuable information on the correlation between algae blooms and weather conditions, namely the role of droughts in these events.

Copyright: Contains modified Copernicus Sentinel data (2020)/processed by A. Cakaj, B. Tomee, L. Sanders, G. Hilgeman