Examining global trends in shallow lakes using satellite derived data from the Climate Change Initiative Lakes_cci project.

The Lakes_cci (Climate Change Initiative) project provides global and consistent satellite observations of Lakes essential climate variables (ECVs): Lake Water Level and Extent, Surface Water Temperature, Ice Cover and Water-Leaving Reflectance (LWLR), capturing both the physical state of lakes and their biogeochemical response to physico-chemical and climatic drivers. Data generated in the project contains products for the period 1992-2020 (v2.0.2), producing data of appropriate quality for climate studies. The Lakes_cci dataset includes 2024 lakes worldwide, covering a wide range of hydro-morphological and ecological characteristics. From this dataset, we selected a subset of shallow lakes (average depth <3m; n=352) distributed globally, in order to investigate long-term timeseries/trends of Chlorophyll-a and Turbidity derived from LWLR. The results will be discussed in relation to lake and catchment characteristics acquired by the HydroLAKES dataset, as well as climatic and demographic variables in order to investigate relationships between water quality trends in shallow lakes and their main environmental and anthropogenic drivers during the last two decades. Shallow lakes and wetlands dominate inland waters and provide many ecological services, being particularly important in carbon storage and biodiversity. Because of their large surface-to-volume ratios, they are prone to environmental changes influenced by nutrient loading and pollutants and are sensitive to climate change.