The Great Pacific Garbage Patch, an enormous area of floating garbage halfway between California and Hawaii, is already recognized as the largest accumulation zone of ocean plastic on Earth. Now, it turns out that researchers may have been vastly underestimating its scale.

The results of a three year mapping effort by international scientists, published Thursday in the journal Scientific Reports, reveals that the amount of plastic this garbage patch contains is up to 16 times greater than initially thought.

According to the study, the patch takes up 1.6 million square kilometers (618,000 square miles), an area about three times the size of France. It contains 1.8 trillion pieces of plastic weighing in at 80,000 metric tons equivalent to 500 jumbo jets.