Text and Photos by Henrylito D. Tacio
Nearly 270,000 tons of plastic, which is enough to fill more than 38,500 garbage trucks, are floating in the world’s oceans. This is based on a study done by 5 Gyres Institute, an organization that aims to reduce plastic in the oceans.
According to a news dispatch released by Associated Press, the researchers dragged a fine mesh net at the sea surface to gather small pieces to gather data. “Observers on boats counted larger items. They used computer models to calculate estimates for tracts of ocean not surveyed. The study only measured plastic floating at the surface. Plastic on the ocean floor wasn’t included,” the news agency reported.
Bits greater than about 8 inches (20 centimeters) accounted for three-quarters of the plastic that the research estimated is in the ocean. The plastic is broken up into more than 5 trillion pieces, said the study which was published in the scientific journal PLOS ONE.
The recent finding is comparable to an earlier study done by researchers in Spain who used different methodology. That said study estimated “there was 7,000 to 35,000 tons of plastics this size floating in the ocean.”
“Once thought to be so vast and resilient that no level of human insult could damage them, the oceans are now crying out for attention,” noted a report released by the Washington-based Worldwatch Institute.
“The world’s oceans are in danger, and the enormity of the challenge is bigger than one country or organization,” said World Bank president Robert Zoellick during the World Oceans Summit held in Singapore some years back.
“We need coordinated global action to restore our oceans to health. Together we’ll build on the excellent work already being done to address the threats to oceans, identify workable solutions, and scale them up,” he added.
The Philippines, which faces the Pacific Ocean, is not spared. In 2012, the results of the Ocean Health Index ranked the Philippines 105th out of 117 territories, making it among the most deteriorated marine ecosystems in the world.
The Index focuses not only how pristine the ocean is but how it can sustainably deliver benefits for the people within its territory. It uses 50 distinct indicators such as the sustainability of methods of seafood harvesting and coastal protection.
Senator Loren Legarda, chair of the Senate Committee on Climate Change, pointed out: “The Ocean Health Index is a new kind of yardstick because it measures how well our oceans can continue to deliver the needs of our growing population. It recognizes people as a legitimate component of ocean health. And based on the recent results, it is clear that the health and socio-economic value of our oceans will continue to deteriorate if we do not innovate our strategies towards their conservation.”
The recent assessment report by the Intergovernmental Panel on Climate Change (IPCC) has confirmed that indeed the world’s oceans are under serious threat. It noted that as a direct result of increased carbon intake, acidification has increased, which has a direct correlation to the overall health and balance of oceanic ecosystems. Furthermore, sea levels are predicted to rise in 95 percent of ocean area.
Professor Alex Rogers of Somerville College, Oxford, and scientific director of International Program on the State of the Ocean (IPSO) said: “The health of the ocean is spiraling downwards far more rapidly than we had thought. We are seeing greater change, happening faster, and the effects are more imminent than previously anticipated. The situation should be of the gravest concern to everyone since everyone will be affected by changes in the ability of the ocean to support life on Earth.”
Senator Legarda agrees. “The destruction of our marine ecosystems will not only lead to the extinction of thousands of species but will also be detrimental to tourism, food supply, and sustenance and livelihood of our fisherfolk. This makes our responsibility over protecting our oceans even greater,” she pointed out.
Among the assessments of factors affecting ocean health, the panel identified the following areas as of greatest cause for concern:
• De-oxygenation: The evidence is accumulating that the oxygen inventory of the ocean is progressively declining. Predictions for ocean oxygen content suggest a decline of between 1% and 7% by 2100. This is occurring in two ways: the broad trend of decreasing oxygen levels in tropical oceans and areas of the North Pacific over the last 50 years; and the dramatic increase in coastal hypoxia (low oxygen) associated with eutrophication. The former is caused by global warming, the second by increased nutrient runoff from agriculture and sewage.
• Acidification: If current levels of carbon dioxide release continue we can expect extremely serious consequences for ocean life, and in turn food and coastal protection; at carbon dioxide concentrations of 450-500 ppm (projected in 2030-2050) erosion will exceed calcification in the coral reef building process, resulting in the extinction of some species and decline in biodiversity overall.
• Warming: As made clear by the IPCC, the ocean is taking the brunt of warming in the climate system, with direct and well-documented physical and biogeochemical consequences. The impacts which continued warming is projected to have in the decades to 2050 include the following: reduced seasonal ice zones, including the disappearance of Arctic summer sea ice by ca. 2037; increasing stratification of ocean layers, leading to oxygen depletion; and increased incidence of anoxic and hypoxic (low oxygen) events.
• The ‘deadly trio’ of the above three stressors – acidification, warming and deoxygenation – is seriously effecting how productive and efficient the ocean is, as temperatures, chemistry, surface stratification, nutrient and oxygen supply are all implicated, meaning that many organisms will find themselves in unsuitable environments. These impacts will have cascading consequences for marine biology, including altered food web dynamics and the expansion of pathogens.
• Continued overfishing is serving to further undermine the resilience of ocean systems, and contrary to some claims, despite some improvements largely in developed regions, fisheries management is still failing to halt the decline of key species and damage to the ecosystems on which marine life depends. In 2012, the UN Food and Agriculture Organization determined that 70% of world fish populations are unsustainably exploited, of which 30% have biomass collapsed to less than 10% of unfished levels.
“From afar, aliens might see the obvious: the sea is Earth’s life-support system,” wrote marine biologist Sylvia A. Earle, former chief scientist of the U.S. National Oceanographic and Atmospheric Administration. “The services provided are so fundamental that most of us who live here tend to take them for granted.”
“The earth’s great sea is the heart of the hydrological cycle – nature’s solar-driven water pump,” explained Don Hinrichsen, an award-winning environmental journalist and author of Coastal Waters of the World.
About 430,000 cubic kilometers of water evaporate from the oceans every year. “Of this amount, around 110,000 cubic kilometers fall as freshwater precipitation over land, replenishing surface and ground waters and eventually completing the cycle by returning to the sea,” Hinrichsen reports.
The ocean is also the engine that drives the world’s climate, storing huge quantities of solar energy in the process. “The ocean absorbs and stores carbon dioxide from the atmosphere,” says Hinrichsen. “Since this invisible gas is one of the main agents of climate change, the ocean is an important sink that helps to modify human impacts on global climate.”
Ocean currents, the blue planet’s super highways, transfer enormous quantities of water and nutrients from one place to another. The Gulf Stream, for instance, pushes more water from the Gulf of Mexico and the Caribbean across the Atlantic into northern Europe, than is carried by all the rivers on earth.
0 Comments
Oldest