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[News] from [guardian.co.uk]

[Environment > Climate Glaciers]
Thinning glaciers driving polar ice loss, satellite survey finds
Satellite survey of Greenland and Antarctic ice sheets reveals extensive network of rapidly thinning glaciers that is driving ice loss in the regions
Ian Sample, science correspondent
guardian.co.uk, Wednesday 23 September 2009 18.05 BST Article history

A comprehensive satellite survey of the Greenland and Antarctic ice sheets has revealed an extensive network of rapidly thinning glaciers that is driving ice loss in the regions.

The most profound loss of ice was seen along the continental coastlines, where glaciers speed up as they slip into the sea. In some regions, glaciers flowing into surrounding waters were thinning by nearly 10m a year.

Scientists used data from Nasa's ICESat (Ice, Cloud and and land Elevation Satellite) to piece together a picture of the changing fortunes of glaciers on the ice sheets. The satellite bounces laser light off the ground, allowing researchers to measure the terrain with extraordinary precision.

The survey, compiled from 50m satellite measurements taken between February 2003 and November 2007, shows glaciers thinning at all latitudes in Greenland and along key Antarctic coastlines. Thinning penetrated deep into the interior of the ice sheets and continues to spread as ice shelves melt into the sea.

"We were surprised to see such a strong pattern of thinning glaciers across such large areas of coastline. It's widespread and in some cases, thinning extends hundreds of kilometres inland," said Hamish Pritchard who led the study at the British Antarctic Survey.

In Greenland, glaciers in the south-east were found to be flowing at speeds of more than 100m per year, during which they thinned by 84cm. More slow-going glaciers lost around 12cm a year.

In a vast region of western Antarctica that drains into the Amundsen Sea, the Pine Island glacier and neighbouring Smith and Thwaites glaciers are thinning by 9m a year, the satellite measurements show. The study is published in the journal Nature.

Previous satellite surveys of polar regions have relied upon radar measurements that cannot map the Earth's surface with the same precision as the ICESat laser rangefinder. The satellite allows scientists to take 65m-wide snapshots of the ground, giving an unprecedented view of glaciers on the steep terrain where ice meets ocean.

This satellite survey helps scientists explore how different aspects of climate change are driving ice loss in polar regions. Higher air temperatures can increase surface melting, but warm ocean currents accelerate ice loss more when glaciers flow into the sea.

"The majority of the thinning we see is not due to increased melting from higher atmospheric temperatures, but because the glaciers are flowing faster thanks to their interaction with the oceans," said Prof David Vaughan, a co-author on the study.


[Environment > Geo-engineering]
China's largest cloud seeding assault aims to stop rain on the national parade
Cloud-seeding aircraft to intercept rainclouds that threaten to cast shadow over communist party's 60th celebrations in Beijing
Jonathan Watts, Asia environment correspondent
guardian.co.uk, Wednesday 23 September 2009 17.41 BST Article history

China's air force is gearing up for its biggest ever assault on the clouds to ensure blue skies above Beijing for the 60th anniversary of communist party rule, local media reported today.

Eighteen cloud-seeding aircraft and 48 fog-dispersal vehicles are on stand-by to intercept rainclouds that threaten to cast a shadow over the festivities, which will include the biggest display of military power in at least 10 years.

The weather modification could exceed the huge cloudbusting operation for the opening ceremony of the Olympic games last year, when more than 1,100 rain-dispersal rockets were fired into the sky.

"It is the first time in Chinese history that artificial weather modification on such a large scale has been attempted," said Cui Lianqing, an air force meteorologist, speaking to the Global Times newspaper.

Meteorologists will coordinate the mission using satellite data. The Beijing Weather Modification Office will supplement the air force's campaign with rockets and planes that load the clouds with silver iodide or liquid nitrogen — dry ice — to induce precipitation above reservoirs and rivers.

China has the world's most extensive rain creation infrastructure, employing about 50,000 people nationwide. Their job is usually to alleviate droughts in the arid north of the country. For national day they would have to encourage rain to fall from clouds before they reached Beijing.

The National Day events mark the founding of the People's Republic of China on 1 October, 1949. The communist party wants to use the occasion to showcase its achievements since Mao Zedong took power.

The centre of the city will be closed off for a huge parade, musical performance and show of military power. Clear skies are needed for the

firework display and fly past by air force jets.

Smog is another concern. Although air pollution has eased since the Olympics, when more than 100 factories were relocated and restrictions were imposed on cars, the Beijing authorities are taking no chances.

Environment officials have said they will inspect construction sites, regulate coal-burning facilities and impose extra restrictions on vehicles with high levels of exhaust fumes.

Inner Mongolia, Henan, Hebei and other neighbouring regions that host large-scale industrial parks have agreed to cooperate in reducing emissions ahead of the anniversary.

Fearing a major pollution incident might dampen the festive mood, the Ministry of Environmental Protection has mounted a week-long inspection of areas where accidents often happen or where dangerous chemicals are produced. Water supplies are being checked more stringently than usual.

Some of the security measures have frustrated many Beijingers. During rehearsals in recent weeks, residents along the route of the parade were instructed not to go on to their balconies or take pictures of tanks and other vehicles.

The authorities have banned the sale of knives in supermarkets and declared a no-fly zone for kites and racing pigeons. Whether non-compliant birds will suffer the same fate as wandering clouds has not been revealed.

Ten years after taking power, Mao Zedong declared a war on nature, including a disastrous campaign to eradicate sparrows, and a commitment to induce rain. "Manmade rain is very important. I hope the meteorological experts do their utmost to make it work," he said.

Today, however, the military admits there is a limit to their ability to control nature. "There are still a lot of uncertainties with the

weather," Cui told the Global Times. Past records suggest there is a 30% chance of rain on October 1, it said.


[Environment > Birds]
Sea eagles hatched in Scotland reach 150-year peak, says RSPB
Thirty-six chicks hatched this year in programme aimed at reviving species that was hunted to extinction
Press Association
guardian.co.uk, Thursday 24 September 2009 11.43 BST Article history

The number of sea eagle chicks born in Scotland has reached its highest level in 150 years, the RSPB said today.

The charity said 36 chicks were successfully hatched in 2009 - eight more than last year.

And two new breeding pairs of the sea eagle — the largest bird of prey in the British Isles — were spotted during the charity's annual survey.

Sea eagles were hunted to extinction in the last century and have now been reintroduced to Scotland.

The last of the birds, nicknamed "flying barn doors" because of their eight-foot wingspan, were shot in 1918.

The Sea Eagles Project to reintroduce the birds to Scotland started in 1975 and involves RSPB Scotland, Scottish Natural Heritage and Forestry Commission Scotland. At least 200 birds and 46 breeding pairs are believed to be living in Scotland.

Last year 44 pairs of breeding birds produced 28 chicks - a record year for the species since the project began. In 2009, two new pairs were found on the Isle of Lewis and Lochaber. A further 20 young birds will be brought to Scotland every year for the next three years. Five of the eaglets will be monitored to help wildlife experts understand more about their habits and keep up with their progress.

Scottish Natural Heritage's Colin Galbraith, who chairs the Sea Eagle Project team, said the record number of the birds now living in Scotland is important progress. "This is the result of a huge effort by many people over the past 30 years," he said.

"It shows what can be done to reinstate a key part of our natural heritage. It remains important however for the population, especially the newly released birds in the east of the country, to be allowed to fully settle in and establish territories."

Professor Jeremy Wilson, head of research for RSPB Scotland, said the sea eagle is an "inspiring" species.

"We are now seeing a steady rise in the breeding population every year, and this will grow further as the juveniles from the east coast reintroduction programme reach sexual maturity in the next couple of years," he said.

"There are plenty of vacant territories available with natural wild prey species to support these birds. As they continue to spread around Scotland's coast, this exciting spectacle will be made accessible to people throughout the country."