Regional Inland Water Quality Monitoring from Space

Monitoring water constituents of inland water bodies using satellites is gaining increasing importance. Image archives of historic satellites represent valuable data sources to analyze the development of constituent concentrations over time and to derive trends. Changing condition in the water quality also mirrors changes in the environmental status of the water body. To understand and manage lake water quality, particularly in the context of global change, we need to understand how and why inland water bodies respond to different drivers across space and time.

Retrieval of various water constituents

Prominent water quality parameters are Chlorophyll-a, total suspended matter (TSM) and coloured dissolved organic matter (CDOM). Through scattering and/or absorption the water colour is affected, and this can be measured optically. Chlorophyll-a is highly correlated with phytoplankton biomass and therefore a common indicator of the lake trophic state. TSM consists of organic and inorganic components and can significantly impact the light fields in the water column. This affects the optical water properties and thereby influences the biological conditions. Colored dissolved organic matter (CDOM) is the optically active component of dissolved organic carbon and also a key indicator of water quality. For more information of water constituent’s retrieval from space click here. Additionally, cyanobacteria occurrences are monitored from space. algae blooms are more and more frequent in many water bodies and northern Germany water bodies are not spared from this trend. For more information of cyanobacteria monitoring from space click here.

Monitoring water quality of Lakes in Schleswig-Holstein

Together with Lake Department of the Landesamt für Landwirtschaft, Umwelt und ländliche Räume (LLUR) a water quality monitoring is realized for various lakes in Schleswig Holstein.

With a focus set on the development of the chlorophyll-a concentration and cyanobacteria bloom occurrences over time. Within this study the information gain is emphasized on the combination of in-situ and remote sensing data. Each lake has its own characteristics depending on its surroundings, its properties, and its geographical location. We gain detailed insight into the lake conditions with the combination of both information sources. Brockmann Consult GmbH contributes the information about the water constituents retrieved from satellite data which is aggregated in Factsheet for each lake (see Factsheet image). The satellite derived information in the Factsheets can be updated frequently.
Furthermore, the lakes of Schleswig-Holstein are included in the Cyanoalert-Service, which provides NRT data via a viewer containing the time series of user-selected parameters.

Exploring water bodies in Hamburg from space

Hamburg has the largest surface water area per inhabitant in the national comparison to other cities. With the Elbe and the Alster Hamburg offers vast possibilities for sport and leisure activities. Brockmann Consult GmbH contributes satellite retrieved water constituents’ measures within the Elbe, the Alster and further water bodies in Hamburg. Together with the Institut für Hygiene und Umwelt (HU) we perform a quality assessment for the retrieved water quality. Brockmann Consult GmbH developed a NRT processing chain Hamburg for this purpose. With this NRT data the quality assessment is frequently updated. Inland water quality retrieval from space in urban areas faces various additional concern which need to be addressed, e.g. the consideration of high volume of ship or boat traffic.