Worldwide detection of plastic from space with the EMIT imaging spectrometer

Since 1970, increased plastic use and waste mismanagement have contributed to environmental pollution leading to the proliferation of microplastics and ocean contamination. Understanding the plastic presence on-land is crucial as most plastic pollution originates from land-based sources. From its vantage point-of-view on the International Space Station, NASA’s Earth Surface Mineral Dust Source Investigation (EMIT) imaging spectrometer can measure surface reflectance spectra across a wavelength range of 380 nm to 2500 nm. We present a study using this instrument to detect distinctive absorption features of High-density polyethylene (HDPE) and Polyvinyl Chloride (PVC) plastics in the shortwave infrared. By applying a column-wise adaptive matched filter and using a library of plastic reflectance spectra, we successfully identified signatures of these two types of plastics across multiple continents between +/- 52 degrees, primarily related to agricultural practices. Our study underscores the importance of monitoring land-based sources of plastic pollution to guide future mitigation strategies.