Lessons Learned in Detecting Japan Tsunami Marine Debris at Sea

A new report issued in January by the NOAA Marine Debris
Program says one of the biggest lessons learned from tracking marine debris
from the Japanese tsunami is a better understanding of use of remote-sensing
Researchers now have a better base of understanding to move
forward with using remote-sensing technologies for at-sea detection of debris,
but the report emphasizes that the human eye is critical to the effort, both in
finding debris and in providing a “ground-truth” comparison to what can be
detected from the air.
Marine debris is very small compared to the North Pacific,
so we need to try as many different methods as possible to locate it,” said
Peter Murphy, regional coordinator for the NOAA Marine Debris Program. “If you
shrank the North Pacific to the size of a football field, even a large object
like the Misawa dock is still equivalent to the width of a human hair, and it
would be a moving hair.
“We learned lessons about what works and what doesn’t work,
so now we have a tool kit of knowledge on the mix of techniques and when to use
them in future projects and responses,” he said.
Before the tsunami, some of the detection technologies, including
several types of satellite sensors, had not been used before to find marine
debris or were in early stages of testing. Because of the extensive efforts and
renewed interest in at-sea detection during the Japan tsunami marine debris
response, the marine debris community learned more about marine debris behavior
and movement and has advanced the state of knowledge on detection of debris at
sea, Murphy said.

Federal, state and local partners focused on finding marine
debris from the Japan tsunami through several detection methods, including
observations from aircraft, unmanned aircraft systems, vessels, shoreline
observers, and satellites. NOAA paired detection with modeling in order to
focus detection resources on areas where the debris was most likely to be
located, given the large area of ocean where the debris dispersed.