Can you clean up the Pacific Garbage Patch?
The answer to this is not as simple as you may think. It is certainly not cost-effective to skim the surface of the entire ocean. Even a cleanup focusing on “garbage patches” would be a tremendous challenge. Keep in mind these points:
- Concentration areas move and change throughout the year
- These areas are typically very large (see below)
- The marine debris is not distributed evenly within these areas
- Modes of transport and cleanup will likely require fuel of some sort
- Most of the marine debris found in these areas is small bits of plastic
This all adds up to a bigger challenge than even sifting beach sand to remove bits of marine debris. In some areas where marine debris concentrates, so does marine life. This makes simple skimming of the debris risky—more harm than good may be caused. Remember that much of our ocean life is in the microscopic size range. For example, straining ocean waters for plastics (e.g., microplastics) would capture the plankton that are the base of the marine food web and responsible for 50 percent of the photosynthesis on Earth… roughly equivalent to all land plants!
Also, keep in mind that our oceans are immense areas! The Pacific Ocean is the largest ocean on the planet covering nearly 30 percent of Earth’s surface area (~96 million square miles, or ~15 times the size of the continental US). Surveying less than 1 percent of the North Pacific Ocean, a 3-degree swath between 30° and 35°N and 150° to 180°W, requires covering approximately 1 x 106 km2. If you traveled at 11 knots (20 km/hour), and surveyed during daylight hours (approximately 10 hours a day) the area within 100m off of each side of your ship (Mio et al., 1990), it would take 68 ships one year to cover that area! Now, add to that the fact that these areas of debris concentration have no distinct boundaries, move throughout the year, and are affected by seasons, climate, El Nino, etc.