Sensing Ocean Plastics with an Airborne Hyperspectral Shortwave Infrared Imager

Area of Science:

• Environmental Science
• Remote Sensing
• Oceanography

Background:

• Ocean plastic pollution is a significant environmental challenge.
• Effective monitoring strategies are crucial for mitigation efforts.
• Remote sensing offers a promising approach for large-scale plastic detection.

Purpose of the Study:

• To demonstrate the feasibility of using airborne shortwave infrared (SWIR) imagery for remote sensing of ocean plastics.
• To identify unique spectral features of plastics in SWIR wavelengths.
• To assess the potential of SWIR technology for detecting and quantifying marine plastic debris.

Main Methods:

• Airborne data acquisition using a C-130 aircraft over the Great Pacific Garbage Patch.
• Collection of red, green, and blue (RGB) and hyperspectral SWIR imagery (950-2450 nm).
• Analysis of SWIR spectral data from 118 identified plastic items of various types and sizes.

Main Results:

• Unique SWIR spectral features common to plastics were identified.
• SWIR spectra exhibited consistent magnitude and shape across different plastic types.
• Simulations confirmed absorption features at ~1215 nm and ~1732 nm are key for plastic detection.

Conclusions:

• Airborne SWIR remote sensing is a viable proof-of-concept for detecting ocean plastics.
• SWIR spectral analysis can differentiate plastics from surrounding seawater.
• This technology can contribute to developing advanced ocean plastic monitoring solutions.