BBC Environmental Science – The thickness of Arctic sea ice “plummeted” last winter, thinning by as much as 49 centimetres (1.6ft) in some regions, satellite data has revealed. A study by UK researchers showed that the ice thickness had been fairly constant for the previous five winters.

The team from University College London added that the results provided the first definitive proof that the overall volume of Arctic ice was decreasing. The findings have been published in the journal Geophysical Research Letters. “The ice thickness was fairly constant for the five winters before this, but it plummeted in the winter after the 2007 minimum,” lead author Katharine Giles told BBC News.

Sea ice in the Arctic shrank to its smallest size on record in September 2007, when it extended across an area of just 4.13 million sq km (1.59 million sq miles), beating the previous record low of 5.32 million sq km, measured in 2005. The team from the university’s Centre for Polar Observation and Modelling - part of the UK’s National Centre for Earth Observation - found that last winter the ice had thinned by an average of 26cm (0.9ft) below the 2002-2008 winter average. Dr Giles added that the data also showed the western Arctic experienced the greatest impact, where the ice thinned by up to 49cm (1.6ft).

The recent record losses of ice cover in the Arctic has led to suggestions that the region could have reached a “tipping point.” (10/28/08)
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BBC Environmental Science — The planet is headed for an ecological “credit crunch”, according to a report issued by conservation groups. The document contends that our demands on natural resources overreach what the Earth can sustain by almost a third.

The Living Planet Report is the work of WWF, the Zoological Society of London and the Global Footprint Network. It says that more than three quarters of the world’s population lives in countries where consumption levels are outstripping environmental renewal.

This makes them “ecological debtors”, meaning that they are drawing - and often overdrawing - on the agricultural land, forests, seas and resources of other countries to sustain them.

The report concludes that the reckless consumption of “natural capital” is endangering the world’s future prosperity, with clear economic impacts including high costs for food, water and energy.

“If our demands on the planet continue to increase at the same rate, by the mid-2030s we would need the equivalent of two planets to maintain our lifestyles,” said WWF International director-general James Leape.

Dr Dan Barlow, head of policy at the conservation group’s Scotland arm, added: “While the media headlines continue to be dominated by the economic turmoil, the world is hurtling further into an ecological credit crunch.”

The countries with the biggest impact on the planet are the US and China, together accounting for some 40% of the global footprint. The report shows the US and United Arab Emirates have the largest ecological footprint per person, while Malawi and Afghanistan have the smallest. (10/28/08)
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