As a sailor, almost nothing is as depressing as seeing pollution in the wide blue ocean.
It's not unusual when we're thousands of kilometres from land and have not seen a ship, plane or person in weeks, to see plastic rubbish floating by. The waste includes bags, old flip flops, diapers, broken pails, combs and styrofoam boxes.
Sometimes, we sail into areas of the ocean where there's so much rubbish it looks like a garbage truck has dumped its load at sea.
One such area is the Pacific Trash Vortex, a floating patch of plastic waste more than 1,000 times bigger than Hong Kong. It is in the middle of the North Pacific where ocean currents dump tonnes of trash from around the world. If you drop plastic rubbish in Victoria Harbour, ocean currents could carry it thousands of kilometres to this vortex between California and Hawaii.
Scientists say that as much as 10 per cent of the 260 million tonnes of plastic produced annually ends up in the oceans. And much of it can be found in huge floating patches like the Pacific garbage vortex.
But not all of the trash is visible on the surface, because most of it breaks up into small pieces and slowly sinks to become a toxic part of the marine environment. Fish and birds eat the plastic, which usually kills them.