The Arctic: Losing Its Cool

Arctic powers the "heat pump"

(TO KNOW More about SAVE UR WORLD!.)

The Arctic is critical to the globe's climate and influence temperatures everywhere.

It sounds counter-intuitive, but the Arctic plays a primary role in distributing heat around the world through what is known as the "heat pump." The ocean's currents circulate heat throughout the world, through a system known as the "great conveyor belt." Two main forces keep the conveyor moving: winds and ocean density differences. The Arctic is key to the density differences.

The conveyor belt's critical points are where surface waters plunge into deep waters. This happens only in a few places, two of which are in the North Atlantic. As the ocean surface waters cool in the far north, they become denser and sink toward the bottom of the ocean. There, the cold water flows toward the equator. This combination of sinking and flow helps drive the ocean conveyor.

Because the cold waters that flow south must be replaced, warm surface currents flow farther north and deliver warmth to places far north. Without the ocean conveyor's heat pump, Europe's temperate climate would be much colder.

Global warming is changing that key spot in the North Atlantic where the surface waters plunge. A mix of increased precipitation, river run-off and melting ice—all related to climate change—is making surface waters in the north less salty and dense, weakening this major pump in the ocean's natural circulation.

Arctic melt is speeding up warming

Also speeding up the Earth's warming is the loss of Arctic ice. Like a mirror, ice bounces sunlight back toward space, preventing sunlight from heating the surface. Winds carry the cooler air down from Canada into the U.S., cooling our climate.

Open water and bare soil are not as bright as ice and snow, so they absorb heat instead of reflecting it. When ice melts, the Earth's darker surfaces are exposed and thus absorb more solar energy. This extra heat melts even more ice, which leads to even more dark surfaces and absorption. This is what scientists call a positive feedback loop. Once the loop gets going, it tends to keep going—and to speed up. Less ice means less cooling much faster. Or, as the American Meteorological Society's senior scientist Susan Joy Hassol put it to U.S. senators in a committee hearing in 2004: "What we're looking at is having a less efficient air conditioner."

Loss of Arctic ice is not just speculation—it's already happening. The year 2003 brought a dramatic example of Arctic ice disappearing. The Ward Hunt Ice Shelf, the largest in the Arctic, broke in two, draining a unique freshwater lake that was home to a rare microbial ecosystem. Since the 1970s, 400,000 square miles of Arctic sea ice has disappeared. That's the size of Texas and California combined. (Intergovernmental Panel on Climate Change [IPCC], 2001) Even worse, the years 2002 through 2006 have all seen record or near-record low ice cover. The most recent report by the IPCC finds that nearly all of the Arctic Ocean could lose year-round ice cover by the end of the 21st century if greenhouse gas emissions reach the higher end of current estimates. (IPCC 2007)

What this means for the rest of us

While the Arctic melt has profound effects on the region's people and ecosystems, it also spells trouble for the rest of the world. For instance, the changes to the ocean's circulation system would mean that though some places will get much warmer, other places, such as Europe, which won't get the warmth from the Gulf Stream, will get much cooler.

One of the thaw's most pressing concerns on the world beyond the Arctic is sea-level rise. When melting glaciers spill into the ocean, sea levels around the globe rise. The booming cities and counties along the East and West coasts house half of the U.S. population and are among the communities that will be most threatened by melting ice.

Currently, the retreat of the world's glaciers is adding enormous amounts of fresh water to the ocean. Between 1961 and 1997, for instance, about 890 cubic miles of ice has been lost. That means that melting glacier ice has added about 980 trillion (or 979,994,261,211,428.5) gallons of water to the oceans. That would be like dumping more than a million Olympic-sized swimming pools into our oceans.

Some studies have even suggested the possibility that warming over the next several centuries would lead to the complete, irreversible disappearance of the Greenland ice sheet. Were that to occur, sea levels would rise an extra 23 feet.

"If we ignore the Arctic's warning—and it is warming—the polar bears and native Alaskans won't be the only ones who suffer," notes Environmental Defense scientist Dr. Bill Chameides. "Our children and grandchildren could pay a hefty price."

Global warming : INDIA

We keep reading about rising temperatures and sea-levels in other parts of the world like United States and the UK, but actually India is one of the most vulnerable countries when it comes to effects of global warming. India has a vast coastal line and the rising sea levels caused by global warming will cause an ecological disaster.

Bengal will suffer
The Himalayan glaciers have started to melt and the average rate of retreat is almost twice (34 metres) per year as compared to the 1971 levels of 19 metres. The melting glaciers will cause temperatures and sea-levels to rise and there will be a cascading effect on the crops and the monsoons. Worse - whole islands are expected to vanish! In fact two have already gone under - two islands in the Sunderbans, an area which India shares with Bangladesh. Temperatures in the group of islands has already gone up by one degree centigrade.

Rising sea-levels will be a disaster
While some climatologists say that sea levels will increase by just 4-35 inches from 1990 levels in another hundred years…some feel that the range could be higher - 20-55 inches. Thats a lot and will affect human habitat in a big way. In fact, as far back as 1993 a study to evaluate the impact of rising sea levels on India was carried out by JNU (Jawaharlal Nehru University). They calculated what would happen if the sea-levels rose by just 1 metre…and they found that as many as 7 million people would be displaced and 5,764 sq km of land and 4,200 km of roads would be lost!

Why is only the east coast of India being affected?
This is because the Bay of Bengal is landlocked from three sides and there is a huge delta of the rivers Brahmaputra and the Ganga. These rivers will carry the water from the melting Himalayan snows. However this does not mean that the western coastal regions are immune…just that the eastern coast is more vulnerable at this stage.

So what are these green house gases which are causing the snows to melt? According to the Wiki greenhouse gases are “include water vapor, carbon dioxide, methane, nitrous oxide, and ozonecomponents of the atmosphere that contribute to the greenhouse effect. Some greenhouse gases occur naturally in the atmosphere, while others result from human activities.

This is the report of UN environmental study......
We are expecting your comments.....

Global warming: Forcing Tuvaluans to migrate!

MOST OF us have not heard about Tuvalu. In fact, what importance can a sparsely populated island – the third least populated country in the world, with an economy that survives on subsistence farming, fishing and foreign aid with no natural resources, be of to the global community? Oblivious to the vast majority of the people on this planet, this tiny Polynesian island nation has succumbed to global warming, forcing evacuation of its inhabitants and creating the first global warming refugees of the world.

Tuvalu, with its four reef islands and five true atolls, lies on the Pacific Ocean, midway between Hawaii and Australia. The rising sea level, the obvious outcome of global warming, is gradually engulfing this island nation. In the next 50 years, the country would completely disappear from the face of the earth. The highest point of the nation is only five meters above the sea level. 3000 Tuvaluans have already been evacuated and the remaining 8000 are waiting to leave the country, sometime in the near future. For the Tuvaluan refugees, challenges of settling in Australia and New Zealand are myriad. Tuvalu was a country where its inhabitants were used to live simple life in small islands with few cars, where locals spent most of the time barefoot on the sand, living in communities where during hot nights one can even sleep on a local airstrip. For these simple islanders, adjusting to large cities with their high-rises and highways is not easy. Nonetheless, Tuvaluans prefer to immigrate to the neighboring countries, as they notice the gradual environmental changes on their island. The Australian Bureau of Meteorology has detected Tuvalu’s sea level rising at a rate of 5.5 millimeters every year, on par with average sea level rise worldwide.

As the Tuvaluans are being displaced from their homes, to add to their woes, the islanders are stranded in a political quagmire, surrounding the definition of the term ‘refugee’.
The United Nations, under the Geneva Conventions, describes ‘a refugee, strictly as a person displaced from his or her homeland because of war or political persecution’. Lack of formal recognition of climate refugees has made Australia, reluctant to grant refugee status to the displaced Tuvaluans. However, the government of New Zealand had generously agreed to accept the climate refugees of Tuvalu, guaranteeing them residency, housing, counseling services and other benefits.

With global warming continuing unabated, it has been estimated that by 2050, there would be 200 million climate refugees worldwide. Particularly vulnerable to the rising sea level are the low-lying coastal countries in the Pacific, most of Bangladesh and big cities like Shanghai, Hamburg, Bangkok, Jakarta, Mumbai, Manila, Buenos Aires, London and Venice. The apathy of the UN and the global community regarding the plight of the climate refugees of Tuvalu would soon change into great concerns, when coastal flooding begins threatening the populous nations of the world.

We are expecting readers comments and reviews about this.