Calgary, October 5, 2016 – The first formal airborne geomatics survey to quantify the extent of the Great Pacific Garbage Patch is now underway, organized and conducted by the Dutch foundation Ocean Cleanup. ITRES and Teledyne Optech are working with Ocean Cleanup in providing a highly sensitive specialized shortwave infrared (SWIR) hyperspectral imaging and Lidar scanning sensor suite to augment a RGB camera and human spotters on the survey aircraft. This airborne survey is currently sensing and scanning thousands of square kilometers of this plastics-dominated patch of ocean.
Last year Ocean Cleanup produced a ship-based high resolution map from a survey that showed the surprising spatial extent of this huge mass of water-suspended plastics.
The Great Pacific Garbage Patch has accumulated half way between Hawaii and California through the action of global ocean currents. Last year’s survey showed the dense heart of this constantly-changing patch to be 1m square km (386,000 square miles) on it’s own; the edges extend to cover more than 3.5 times this extent. This is one of the largest patches found, others exist elsewhere.
This year’s goal is to accurately quantify the volume of these plastics in the Great Pacific Garbage Patch. Ultimately, the foundation is actively developing new technologies designed to filter and clean these plastics from ocean bodies.
The process of quantification must take into account the wide range in size of the plastics that have accumulated, microscopic to metres in size. To this end, Ocean Cleanup has equipped a C-130 Hercules aircraft with the latest SWIR optical imaging and Lidar technologies.
Working with Teledyne Optech, ITRES provided a high-performance hyperspectral SASI to provide SWIR imaging capability through integration with the Teledyne Optech CZMIL bathymetric Lidar.
The SASI provides high spatial and spectral resolution imaging across SWIR wavelengths of 0.95 to 2.45 microns, a spectral region associated with strengths in differentiation of different types of clays as well as plastics, paints, and other manufactured materials. Initially developed for the detection of surface-laid land mines, this mapping imager has long seen use by clients globally for environmental or civil projects where being able to detect, map, and quantify human-made materials from their natural surroundings is required.
Why the SASI?
A simple illustration of the SASI’s use in detecting plastics and other anthropomorphic materials can be seen below. These images were taken in 2005 using an early-model SASI imager, the first such commercial SWIR imager on the market. Despite the age of the examples that follow, they clearly illustrate the power of this spectral region in detecting materials of the type accumulating in the Great Pacific Garbage Patch.
Depending on the spectral wavelength being displayed from this hyperspectral dataset, skin, various plastics, painted and/or pigmented materials, and concentrations are easily observed without the need for high level image processing or analysis.
ITRES has a long history of working with groups requiring high performance hyperspectral and broadband imaging technologies for environmental surveys, such as CSIRO, NOAA, and JALBTCX.
More information on the Ocean Cleanup’s activities can be found at the foundation’s website:
Ocean Cleanup facebook page:
Information on the SASI-1000A:
Information on the Teledyne Optech CZMIL Lidar and its use with the Ocean Cleanup project: