Warming In Antarctica: cause for concern : Melbourne Indymedia

Disappearing sea ice and warmer temperatures in the Southern Ocean around Antarctica are causing an 80 percent drop in the numbers of Antarctic Krill. Krill, a small custacean which feeds on algae under ice sheets, is at the bottom of the food chain. Penguins, seals, fish, sea birds and whales are all dependent on Krill as a food source. This will also impact southern Fisheries. A new study released 3 November in the journal Nature, revealed the extent of the problem.

Angus Atkinson, a marine biologist at the British Antarctic Survey, said "This is the first time that we have understood the full scale of this decline,"

"The Antarctic Peninsula, a key breeding ground for the krill, has warmed by 2.5 degrees Celsius in the last 50 years, with a striking decrease in sea-ice," Atkinson said in a statement. "We don't fully understand how the loss of sea ice here is connected to the warming, but we believe that it could be behind the decline in krill."

The air temperature increase is about five times faster than the global mean rate.

"We're already seeing some effects in certain penguin species at several sites in this area where krill are declining so much," Atkinson said.

Previously, estimates were based on local surveys so scientists had only suspected that stocks of krill were dropping. The latest figures are derived from data between 1926 to 2003 covering 40 Antarctic summers that was gathered by nine countries working in Antarctica.

"We need to understand the mechanisms of these ecosystem interactions to be able to predict what is going to happen in the future. The key thing is the climatic change at the Antarctic Peninsula. It is this particular area that is warming up." said Atkinson

Antarctic Glaciers on the move

Ice shelves are not only important for stocks of Krill. It has been known for sometime that the various Antarctic ice shelves slow down or hold glaciers from dispensing their huge load of ice into the surrounding waters.

Under the influence of global warming, when ice shelves break up, as in the Larsen B ice shelf in 2002, or in 1995, it releases the blocked glaciers, which now flow up to eight times faster than before into the Weddell Sea.

Ice shelves displace their own weight in water, however glaciers rest on land and when they slide off into the water, they instantly affect sea levels.

Studies from climate researchers and the U.S. space agency NASA show the glaciers are flowing into Antarctica's Weddell Sea, freed by the 2002 breakup of the Larsen B ice shelf.

The researchers come from teams at NASA's Jet Propulsion Laboratory in Pasadena, California, the National Snow and Ice Data Center at the University of Colorado in Boulder, and NASA's Goddard Space Flight Center in Greenbelt, Maryland. They claimed that satellite measurements suggest climate warming can lead to rapid sea level rise, and also prove that ice shelves hold back glaciers.

"If anyone was waiting to find out whether Antarctica would respond quickly to climate warming, I think the answer is yes," said Dr Theodore Scambos, a University of Colorado glacier expert who worked on one study.

In the past 30 years, ice shelves in the Antarctic peninsula region have lost more than 13,500 square kilometers of area.

"The Larsen area can be looked at as a miniature experiment, showing how warming can dramatically change the ice sheets, and how fast it can happen," Scambos said.

"At every step in the process, things have occurred more rapidly than we expected."

Scambos warned what would happen if climate warming occurs in places like the Ross Ice Shelf: "it is a harbinger of what will happen when the large ice sheets begin to warm," Scambos said. "The much larger ice shelves in other parts of Antarctica could have much greater effects on the rate of sea level rise." If the glaciers held by the Ross Ice Shelf melted completly the sea level could rise by 5 metres in a worst case scenario.

By Michelle Nichols

CANBERRA, Oct 22 (Reuters) - As Russia prepares to vote to ratify the Kyoto protocol and allow the global climate change pact to come into force, Australia's conservative government remained adamant on Friday it would not approve the treaty.

The stand by the government, which will be sworn in for a fourth term on Tuesday, comes after a series of storms, droughts and heat waves that suggests global warming might be having a faster impact on climate change than previously thought.

A record 10th typhoon of the season struck Japan this week, killing at least 69 people, while four hurricanes lashed Florida and the Caribbean over a five-week period recently.

Prime Minister John Howard argues that Australia will meet the targets for greenhouse gas emissions set at Kyoto, but will not ratify the pact because he believes it would push industry and jobs offshore to countries which do not back the agreement.

"The government will not sign the Kyoto protocol. Australia is already reducing greenhouse gas emissions," a spokesman for Howard told Reuters on Friday.

The government has long said that the Kyoto treaty -- aimed at cutting emissions of gases such as carbon dioxide which are blamed for global warming -- could not work because top polluters such as the United States and China would never comply.

"Therefore it would be more attractive for industry to invest in those countries rather than Australia and that would take investment and also jobs out of our country," Howard told Australian radio earlier this month.

Howard's view is similar to that of U.S. President George W. Bush.

Greenpeace disputed the Australian leader's argument.

"By locking us out of Kyoto ... John Howard is making it more expensive and more difficult for Australian companies to do their bit to tackle climate change," Danny Kennedy, Greenpeace Australia Pacific Campaigns manager, told Reuters on Friday.

EXTREME WEATHER

"John Howard must respond to the weight of public opinion, the necessities of global business and increasing extreme weather by ratifying the Kyoto Protocol and joining the international effort to tackle climate change, the greatest challenge of our age."

Australia is one of the world's top carbon dioxide producers on a per-capita basis and its energy resources are a major source of wealth and jobs. Energy exports are worth more than A$24 billion ($17.5 billion) a year.

U.S. climate experts said on Thursday that extreme weather such as the heat waves that killed tens of thousands of Europeans last year is only the beginning.

Ice is melting faster than anyone predicted in the Antarctic and Greenland, ocean currents are changing and the seas are warming, the experts said.

"This year, the unusually intense period of destructive activity, with four hurricanes hitting in a five-week period, could be a harbinger of things to come," one of the experts, Dr. Paul Epstein, associate director of the Center for Health and the Global Environment at Harvard Medical School, told reporters.

Russia's parliament was due to vote on Friday on ratifying the Kyoto Protocol, the last hurdle before the long-delayed treaty comes into force.

Kyoto becomes binding once it has been ratified by 55 percent of the signatories, which must altogether account for 55 percent of developed countries' carbon dioxide emissions.

So far 126 countries have signed but they only make up 44 percent of emissions by rich nations. Russian ratification will take that figure through the 55 percent threshold.

China has approved the treaty but has no obligation to cut carbon dioxide emissions during the pact's first phase to 2012.

The China Daily said on Thursday the government is drafting a law requiring power companies to buy electricity generated by green energy sources. ($1=A$1.35)

Let's get a perspective on this. The Antarctic Peninsular is the long point that reaches northward towards Chile. It's most northerly point is well above the Antarctic Circle.

For anyone who has been to Finland and seen the Arctic Circle at Rovaniemi, the end of the Peninsular is equivalent to about half way down the west coast of Finland. Finland gets into the 20 degrees there and the major for that part of the Antarctic to be so cold is the wind.

The other important aspect of that region is that the Wedell Sea is the turning point for sea currents which carry water from the Pacific and Indian Oceans up into the Atlantic. (I hope realise that the Pacific has been a bit warm of late.)

A bit of web research shows that the ice shelves there have been breaking up for the last 30 years although the extent has increased of late. Larsen B lost a big piece in 1998 as well as in 2002.

One theory is that summer melt water gets into cracks and when it re-freezes, it forces the cracks to be wider. Another suggests a change in precipitation causing structural weakness in the ice. A third suggests under-cutting either the ice or the material that it sits on. (Note that the breakage leaves a piece further out to sea and this means the weakness is not at the extreme edge.)

There's also reports of a change in winds (the Antarctic Vortex) and this seems to have brought warmer conditions to some areas of the Antarctic but colder conditions to others. (Some regions had their coldest recorded temperatures just a few years ago.)

Lots of theories, lots of ideas, but nothing conclusive.

Krill. Pretty important in the chain. Feed on microscopic life that lives near the sea surface.

Probable cause of krill decline is a decline in the food available to it. The Antarctic hole in the ozone layer has meant lots more UV radiation and that has probably been detrimental to the micro-organisms that live near the surface of the sea.

This would suggest that it's not man-made GW that's doing the damage as much as the aerosols and other ozone-depleting substances that we used to use (and thankfully have banned here in Oz).

cheers

John

There is no use discussing this issue or any possible solutions because they are not just waiting, but hoping for the end. They think that this is Judgement Day and they will survive and the rest of us will die. That is what they want.

I think the best way to call attention to the horrific results of man's unkindness to nature, you have to make a movie about it. Sad, but true - but it on the Big Screen. And quick! (Actually a quicktime video or PSA you have created can be sent to: theprimespot@yahoogroups.com)

Check out earthcharter.org and if you are in the 90800 area, http://www.earthneighborhood.com ....

Ocean Food Chain crashing due to Antarctic Warming

Antarctic Glaciers on the move