Oxygen-starved oceans rapidly dying

BY ROSSLYN BEEBY, SCIENCE AND ENVIRONMENT REPORTER

25/06/2008 7:09:00 AM

The world’s coastal oceans are in crisis, with oxygen-starved ”dead zones” increasing by a third in just two years as global temperatures increase with climate change, according to the International Whaling Commission’s latest scientific report.Dead zones, caused by over-enrichment of waters by nutrients from run-off, sewerage and warming waters, represent ”the worst-case scenario for coastal biodiversity” and are the ‘’severest form” of ocean habitat degradation, the report says.The number of ocean dead zones has grown from 44 areas reported in 1995 to more than 400, with some of the worst oxygen-starved areas extending over 22,000sqkm.

Recent figures from the United Nations Environment Program estimate fertilisers, sewage and other other pollutants, combined with the impact of climate change, have led to a doubling in the number of oxygen-deficient dead zones every decade since the 1960s.

more

Acid rain threatens Adirondacks

Laura Grace Thomas, Foreign Correspondent

The rest of the world may have forgotten about acid rain – turning our heads towards such modern green concerns as biofuels and carbon footprints – but the folks of the Adirondacks in far northern New York have not. It was here that the phenomenon began in the 1970s, when scientists noticed freshwater fish dying in remote lakes and streams. As the term gained gravitas, it was splashed across front pages and activists’ T-shirts from Dubai to Denver. There was even Acid Rain the band.

When George HW Bush as president signed the Clean Air Act of 1990, designed to significantly reduce the precursors of acid rain – sulphur dioxide and nitrogen oxide – Adirondack State Park became the symbol of the fight against rising acidity levels in the United States. By the time the act was passed, it was already too late for 352 of the Adirondacks’ 1,460 lakes – they had been pronounced dead.

The Clean Air Act served as an effective umbrella for acid rain, reducing sulphur dioxide emissions by as much as 10 tonnes. But levels of nitrates have not decreased. This month, scientists published data that suggests soils in the Adirondacks are steadily increasing in acidity, thrusting the park back into the limelight and acid rain back into everyday conversation.

more