Measuring Water Quality From Outer Space
USING SATELLITES to measure water quality
A team of international researchers has recently demonstrated that water quality can be assessed from outer space.
Researchers from the University of Leicester, the Hungarian Academy of Science and industrial partners published in Elsevier, have successfully used satellite technology to visualize pollution levels otherwise invisible to the human eye through ‘Superhero vision’.
While these methods have previously been used for seas and oceans, they are not readily available for lakes, especially shallow lakes with complex optical environments defined by a mix of different natural substances in the water.
The study focused on Lake Balaton, which is Central Europe’s largest lake and a popular tourist spot. The lake’s “very shallow depth means that Balaton is a unique system, as both a habitat and a recreational resource, but also in terms of its optical properties,” the study said.
Using the Medium Resolution Imaging Spectrometer (MERIS) found on the ENVISAT satellite, the researchers were able to observe algal blooms and how they develop.
More than 1,000 satellite images turned into maps of the green chlorophyll concentration in the water, and their quality checked with over 250 ship-based measurements taken over five years.
“It is incredible that such ecological differences occur within one given lake and this makes Lake Balaton so special and suitable for remote sensing projects. The work of Stephanie Palmer has proved that with proper calibration remote sensing is a valuable tool not only for water quality assessment but also for algologists.”, added Viktor Tóth, research fellow of the Balaton Limnological Institute
Satellite sampling of data provided more depth and accuracy, which overcomes hurdles in accuracy and validity using standard collection methods of checking water quality using water samples taken from ships. It also saves money and time, and supports public policy efforts around pollution reduction.