US researchers have unveiled a new method for tracking microplastics in the ocean using satellite data. Their results are confirmed by field observations.
Scientists at the University of Michigan have developed an innovative way to use NASA satellite data to track the movement of tiny pieces of plastic in the ocean.
The researchers explained that microplastics are formed when plastic debris in the ocean is destroyed by the sun’s rays and the movement of ocean waves. These small pieces of plastic are harmful to marine life and ecosystems. Microplastic travels with ocean currents hundreds and thousands of kilometers from the source, making it difficult to track and remove. Now the main source of information on the whereabouts of microplastics comes from fishing trawlers that use nets to catch plankton – and microplastics at the same time.
The new method is based on data from NASA’s Cyclone Global Navigation Satellite System (CYGNSS), a constellation of eight small satellites that measure wind speeds over Earth’s oceans and provide information on the strength of hurricanes. CYGNSS also uses radar to measure the “roughness” of the ocean, which is influenced by several factors, including wind speed and debris floating in the water.
Scientists were interested in the opposite data – the team looked for places where the ocean was smoother than expected, this could indicate the presence of microplastics. They then compared these locations with observations and model predictions of microplastic accumulation in the ocean. Scientists have found that microplastics tend to be present in smoother waters, demonstrating that CYGNSS data can be used as a tool to track microplastics in the ocean from space.