Exploring the satellite-derived Lakes variables for climate studies

Lakes are responding quickly to climate change, and it is expected that in coming decades global warming will have an even more pronounced impact on biodiversity, nutrient cycling, and hydrology. To support the comprehension of this topic at global scale as well as for understanding the complicated behavior of lakes in a changing environment, satellite technologies provide a unique source of data. In such a context, Lakes_cci project recently provided the most complete collection of consistent satellite observations of water level, water extent, lake surface water temperature, water-leaving reflectance and related chlorophyll-a concentraNon and turbidity and ice cover. The products span from 1992 to 2020 over 2000 relatively large lakes, which represent a small fracNon of the number of lakes worldwide but a significant fracNon of global freshwater surface. To illustrate the project's scientific contribution, two use-cases are described in this study. The first use-case is motivated by the increased risk of wildfire driven by high temperatures, low precipitations, and dry vegetaNon can have a substantial hydro-geomorphological effect on watersheds: post-fire precipitaNon can lead erosion and transport mechanisms potently affiancing water quality. The use-case investigates the response, if any, of chlorophyll-a and turbidity to fire effects via terrestrial pathway; it is conducted across a variety of geographic regions and fire regimes. The second use case focuses on shallow lakes distributed globally as, in comparison to deeper lakes, they have received less attention in the climate change context. The use-cases hence examines long-term time-series of bio-physical parameters, as chlorophyll-a, turbidity and water temperature, in view of understanding possible causes of their trends.