5 Gyres - Understanding Plastic Pollution Through Exploration, Education, and Action

(Marcus Eriksen reports from the North Pacific Gyre)

“Is that some kind of Jelly?” someone asked. A gallon of little red jellies filled our trawl. They were not there in the previous trawl or the one after. A jelly patch in the garbage patch (would that be a “JAM” session?). We are following the route Captain Moore took through the Eastern Garbage Patch in 2000, north from Hawaii to latitude 40°N, then east. We’re on the same track. We’re finding far less plastic than last week in the waters just north of Hawaii.

The field of debris seems to come and go. We left Hawaii with sea surface temperatures between 24°-26°C, then it dropped to 18°C about 600-800 miles N. Plastic concentrations dropped. Did we actually go beyond the Transitional Zone Chlorophyll Front (TZCF), where other scientists have shown plastic accumulation and phytoplankton production happen in a temperature band at 18°C? Did we venture from the Subtropical Gyre into the Subpolar Gyre?

 We got as high as 43°N and returned to 40°N to cover the tracks of our earlier voyage 11 years ago. Our manta tows have few visible fragments of plastic, though we’re in the accumulation zone. Is there a decreasing trend in plastic pollution out here? If so, where did it go? Or maybe the patch is as amorphous and elusive as we believe it to be.

In the end we will add data from this expedition to all others, look for spatial and temporal patterns, and hopefully have a clearer picture of the ultimate fate of plastic pollution. It’s now 6pm and time to retrieve the manta trawl. I hope it’s not full of goop. I’m running out of sample jars to put it in.