You are here:
Exploring the potential value of satellite remote sensing to monitor chlorophyll-a for U.S. lakes and reservoirs.
Citation:
Papenfus, M., B. Schaeffer, A. Pollard, AND K. Loftin. Exploring the potential value of satellite remote sensing to monitor chlorophyll-a for U.S. lakes and reservoirs. ENVIRONMENTAL MONITORING AND ASSESSMENT. Springer, New York, NY, 192:808, (2020). https://doi.org/10.1007/s10661-020-08631-5
Impact/Purpose:
Water quality monitoring is essential for maintaining aquatic resources that are safe and healthy for many uses such as drinking water, recreation, agriculture, and for maintaining the integrity of many ecological resources. Chlorophyll-a (chl-a) is an important indicator for excess nutrients in aquatic systems. The contributions of this study are: (a) a comparison of the spatial and temporal distribution of available chl-a observations across different in situ and satellite-based datasets on a national scale; (b) computation of the avoided costs associated with making remotely sensed data available nationally in lieu of in situ sampling, and (c) characterization of land ownership and select sociodemographic variables surrounding waterbodies that are resolvable in both types of datasets. The primary findings suggest that using satellite-based water quality observations to complement traditional in situ monitoring data can be a cost-effective approach, especially when monitoring for water quality variables requiring frequent monitoring. The annual avoided costs associated with using data from the Sentinel-3 and Landsat satellites range from $3.2 to $24 million for this single water quality parameter. The spatial coverage provided by the satellite platforms is comparable to that provided by in situ monitoring programs when compared along sociodemographic characteristics of the communities surrounding the measured waterbodies.
Description:
Assessment of chlorophyll-a, an algal pigment, typically measured by field and laboratory in situ analyses, is used to estimate algal abundance and trophic status in lakes and reservoirs. In situ-based monitoring programs can be expensive, may not be spatially and temporally comprehensive and results may not be available in the timeframe needed to make some management decisions. Satellite remotely sensed chlorophyll-a offers the potential for more geographically and temporally dense data collection to support estimates when used to augment in situ measures. The annual potential avoided costs associated with increasing the availability of remotely sensed chlorophyll-a values were estimated at $3.2 to $24 million depending upon the satellite program used. We also compared sociodemographic characteristics of the regions (both public and private lands) covered by both remote sensing and in situ data to check for any systematic differences across areas that have monitoring data. This analysis underscores the importance of continued support for both field-based in situ monitoring and satellite sensor programs that provide complementary information to water quality managers, given increased challenges associated with eutrophication, nuisance, and harmful algal bloom events.
URLs/Downloads:
DOI: Exploring the potential value of satellite remote sensing to monitor chlorophyll-a for U.S. lakes and reservoirs.