The earth’s imperiled oceans
Here are ten interesting facts about the world’s oceans I gleaned this morning from an insert in the new issue of Economist magazine (3 January 2009), not exactly Europe’s Marxist Review – I realized the situation in the oceans wasn’t altogether hopeful a while ago (back when I was heavily involved in coaching debate competitors, one of the annual high school resolutions related to the oceans). But the story is pretty grim. Quoting the Economist, and in no particular order of priority:
1. The surface of Mars is better mapped than the world’s oceans.
2. Some scientists, citing increasing levels of sea water acidity (30% more acidic since the start of the Industrial Age), believe that coral reefs, home to a quarter of all marine species, may virtually disappear within a few decades. That would be the end of the rainforests of the seas. Already only 5% of the world’s coral reefs can be considered pristine.
3. Because of fishing, over three-quarters of all marine species are below, or on the brink of falling below, sustainable levels. Ninety percent of the world’s large predatory fish (a category including tuna, swordfish and sharks) are gone. In estuaries and coastal waters, 85% of the large whales have disappeared and nearly 60% of the small ones. An article published in Science by 14 academics in 2006 calculated that the accelerating erosion of biodiversity, often associated with overfishing, presages a “global collapse” to the point, in 2048, where all species currently fished will be gone.
4. There are two swirling masses of discarded plastic that have intensified in density and which form clots in the Pacific Ocean. Each of these swirling masses are as large as the United States of America. In 2006 the United Nations Environment Programme estimated that every square kilometer of sea held nearly 18,000 pieces of floating plastic. Each of those two swirling masses is estimated to suspend 50 million tons of plastic junk.
5. According to a report from Britain’s Royal Society, it will take tens of thousands of years for ocean chemistry to return to a condition similar to its pre-industrial state of 200 years ago. Many scientists fear that some changes are reaching thresholds after which further changes may accelerate uncontrollably. An example: No one fully understands why the cod have not returned to the Grand Banks off Canada, even though no one has been fishing for cod for the last sixteen years.
6. Over half the world’s people live within 62 miles of an ocean coast, and a full tenth live within 6.2 miles. These are the populations most immediately jeopardized by rising sea levels caused by global warming.
7. Every year more than 15.8 million gallons of oil run off America’s streets and via rivers and drains find their way into the oceans.
8. A modest indicator of the potential consequences of sea level rise: Were the oceans to rise only an additional 80 centimeters, the New York City subway system would be flooded.
9. Seventy one percent of the earth’s surface is covered by water.
10. For nearly thirty years, legal control of the sea (and thus the limit of development, mining, and drilling operations) has stopped 200 miles from the shore. In 1982, the United Nations Convention on the Law of the Sea set in motion an expansion of these limits. So long as a nation can produce credible scientific data documenting that its continental shelf actually extends fully 200 miles off its coastline, and so long as the extra margin is at least 100 miles from the point at which the sea reaches a depth of 2.5 km, they will be granted rights over the resources on or under the seabed up to 350 miles from land. The profits enabled by this expanded definition shifted the Bush Administration from opposition to the treaty; it now supports American ratification. The deadline for submitting the first major round of claims is May 13, 2009. Roughly 15 million square kilometers are at stake. Australia alone proposes to open up an additional 2.5 million square kilometers to mining and drilling. Environmentalists oppose deep seabed mining since dredging operations stir up quantities of sediment sufficient to kill everything nearby.
Monday, January 5, 2009