Scientists have found that there are at least five large garbage patches polluting the oceans. Some of them are twice as big as the state of Texas. The study, conducted by researchers at the University of New South Wales (UNSW) in Australia, appeared in the journal Chaos, which is published by the American Institute of Physics. Using computer simulation, scientists said they may be able to determine which countries are the biggest polluters.
How are garbage patches formed?
That would be a big challenge considering the complexity and enormity of the oceans. The USNW mathematician and co-author Gary Froyland said some countries could be far away from the garbage patch they are contributing directly to. For instance, Mozambique and Madagascar both nations border the Indian ocean. But the garbage from these countries would likely flow into south Atlantic rather than being sucked into the Indian ocean.
Oceanographer and co-author of the study, Erik van Sebille, said that they can use the new model to assess how quickly garbage from Australia ends up in the north Pacific. Garbage patches in oceans are formed by powerfully rotating water currents. The five large patches are located each in the north and south Atlantic, north and south Pacific, and the middle of the Indian ocean.
The garbage patches resemble a thin soup of plastic
These pollutants raise serious environmental concerns because broken plastic spreads easily. Plastic trash is toxic to marine life. The plastic comes mainly from litter that is left on beaches, falls off the boats or washes downstream in rivers. People usually picture these garbage patches as islands of trash. But Froyland said they resemble a thin soup of plastic. Churning waters and UV rays break the debris down in tiny pieces that are easily consumed by marine animals.
The main purpose of the study was to find out how well the surface water of oceans mixes. Their new model showed that parts of the Indian and Pacific oceans are closely coupled with the south Atlantic. Another part of the Indian ocean belongs in the Pacific ocean. It will help biologists track ocean debris. What’s more, a better understanding of ocean geography will offer fresh insights into the marine ecology.