By Peter Murphy, Alaska Regional Coordinator, NOAA Marine Debris Program
One of the challenges NOAA faces when addressing marine debris is finding it. That may seem odd when you think of bottles and trash on your nearest beach, but it becomes much more difficult in the open ocean. Debris – including items from the 2011 tsunami in Japan – is difficult to locate reliably.
In addition to the fact that debris sometimes floats just below the water’s surface, it can be spread out across huge stretches of ocean. Imagine a search area roughly three times the size of the continental United States. Even when we look at an area where we know there is likely to be debris, we may not detect anything. That could be because there isn’t anything there to see (less likely) or because our sensors aren’t able to detect what is there (more likely).
However, NOAA is looking at many innovative ways to solve that challenge. Earlier this summer, we tested an Unmanned Aircraft System (UAS) off the coast of Oʻahu to see if it might be an effective new technology to help locate debris at sea.
The test was a good step forward in the process. Since then, many people have asked whether we’re ready to use the UAS to locate tsunami debris. The answer is no, not yet.
What did we do?
During the test, researchers placed simulated debris of varying sizes, shapes and buoyancies in the water and launched the UAS (which resembles a model airplane) from a vessel over the items. We also took advantage of the fact that we had control over the debris’ location to test whether different satellite sensors could detect it in the water.
In the end, the plane’s camera was able to capture clear images of the debris in the water and the vessel itself. We are still analyzing the satellite imagery, which can be tricky if there’s cloud cover, to see which sensors could detect the debris.
We still have many more questions to answer and logistics to work out before a UAS can be applied to real-world marine debris detection. We’ll keep you updated on next steps, but until then, here are a few photos from the demonstration: