Report warns of mass extinctions of fish and other marine life - urges slashing CO2 emissions
22/6/2011 New Scientist Mass extinctions are seldom pretty, but this one would transform Earth’s oceans forever, especially coral reefs.A new report by the International Programme on the State of the Ocean (IPSO) assesses how climate change, overexploitation, pollution, habitat loss and other stressors are affecting the ocean as a whole.
The conclusion? We’re on course for a mass extinction that would include coral reefs and the menagerie of species that rely on them, as well as multiple species of fish consumed by people, although it may not be as severe as the “big five” extinctions of Earth’s distant past.
“We’re seeing a combination of symptoms that have been associated with large, past extinctions,” says Alex Rogers, the head of IPSO.
Acidifying waters
Rogers says the biggest problem is the rapid pace of climate change, which is “virtually unprecedented”. The closest comparison is the Paleocene-Eocene Thermal Maximum of 55 million years ago, when 2.2 gigatonnes of carbon dioxide was released every year for millennia and many deep-sea species were wiped out. Today we release over 25 gigatonnes every year.
Many harmful factors combine to cause additional damage. For instance, the oceans are acidifying as a result of CO2 dissolving in the water, and this makes corals more susceptible to “bleaching”.
Rogers recommends nothing less than slashing CO2 emissions, establishing Marine Protected Areas covering up to one-third of the ocean, and restoring marine ecosystems.
Go to: http://www.newscientist.com/article/dn20595-earths-oceans-on-course-for-mass-extinction.html