Polar ice loss quickens, raising seas

[MST]

Ice loss from Antarctica and Greenland has accelerated over the last 20 years, research shows, and will soon become the biggest driver of sea level rise.

From satellite data and climate models, scientists calculate that the two polar ice sheets are losing enough ice to raise sea levels by 1.3mm each year.

Overall, sea levels are rising by about 3mm (0.12 inches) per year.

Writing in Geophysical Research Letters, the team says ice loss here is speeding up faster than models predict.

They add their voices to several other studies that have concluded sea levels will rise faster than projected by the Intergovernmental Panel on Climate Change (IPCC) in its landmark 2007 assessment.

By 2006, the Greenland and Antarctic sheets were losing a combined mass of 475Gt (gigatonnes - billion tonnes) of ice per year.

On average, loss from the Greenland sheet is increasing by nearly 22Gt per year, while the much larger and colder Antarctic sheet is shedding an additional 14.5Gt each year.

If these increases persist, water from the two polar ice sheets could have added 15cm (5.9 inches) to the average global sea level by 2050.

A rise of similar size is projected to come from a combination of melt water from mountain glaciers and thermal expansion of seawater.

"That ice sheets will dominate future sea level rise is not surprising - they hold a lot more ice mass than mountain glaciers," said lead author Eric Rignot from Nasa's Jet Propulsion Laboratory (JPL) in Pasadena, California.

"What is surprising is this increased contribution by the ice sheets is already happening."

Grace on fire
Extending this rate of ice loss forward to 2100, the sea level rise contribution from the two ice sheets alone is calculated at 56cm (22 inches).

By contrast, the IPCC in 2007 projected a maximum rise of 59cm, while acknowledging this was likely to be an under-estimate because understanding of processes happening on ice sheets was insufficient to enable reliable estimates to be made.

Since 2007, several other research groups using diferent methods have concluded that a figure between one and two metres is likely - which would have profound consequences for island nations and countries with long, low coastlines such as Bangladesh.

"If present trends continue, sea level is likely to be significantly higher than levels projected by the IPCC," said Dr Rignot.

"Our study helps reduce uncertainties in near-term projections of sea level rise."

The new research combined two different methodologies.

One calculates ice gain and loss through combining various types of satellite reading and data taken on the ground, for example the thickness of the ice sheet and the speed at which glaciers are moving.

The second dataset comes from Nasa's Grace mission, which uses twin satellites to measure variations in the Earth's gravitational pull.

Ice loss causes a fractional reduction in gravity at that point on the Earth's surface.

Two years ago, this mission surprised some in the research community by showing that even the vast and frigid East Antarctic ice sheet was losing some of its mass to the oceans.

BBC

 

[IBRIS]

Did we have any pact with Maldivians for there evacuation plan in case of sea level rose in future. What will happen to Bangladesh's coasts.?

 

[KS]

More immigration.

 

[IBRIS]

More immigration.

I'm in favor of Maldivians moving in only. Others just not trust worthy, their loyalty lies to their oppressors. Ungreatful people should not be allowed to cross the fence.

 

[DelhiDareDevil]

I saw Human Planet documentary from BBC, and it shows Bangladesh lossing 100 meters of earth, to the river in 5 years only.

Incredible. Bangladesh is getting smaller quicker then I thought.

And I saw no wall defences against the river at all.

 

[indopak]

more trouble for north east and india at large.

 

[IBRIS]

I saw Human Planet documentary from BBC, and it shows Bangladesh lossing 100 meters of earth, to the river in 5 years only.

Incredible. Bangladesh is getting smaller quicker then I thought.

And I saw no wall defences against the river at all.

Human catastrophe is going to be very overwhelming for their establishment. Hopefully razakars would take some action on time!, sadly they would only think about annexing the government rather than building bridges.

 

[true_indian]

Did we have any pact with Maldivians for there evacuation plan in case of sea level rose in future. What will happen to Bangladesh's coasts.?

You gotta be kidding me? Maldives is an hundred percent Islamic nation..They don't allow non-muslims in their country. As a tourist, you are not allowed to carry any pictures of your faith. They also have worst form of blasphemy laws.

I'll tell you an incident that recently happened. An Indian teacher in Maldives draws '+' symbol in his math class. The students in his class misunderstands him to be propagating Christianity. So you know what they and their parents did, they tied the teacher to a chair and thrown him off the island into the sea. This is just one example of several I could think off right now.

Also one of the Mumbai attackers allegedly was a Maldivian trained in Pakistan. Their own minister revealed this in their parliament. You cannot believe how backward those people are in their mentality. They are just as worse as Arabians in treating Indians and Bangladeshis. Their ruling political party is trying to be secular but most Maldivians are anything but secular. They are just courting us because they need us for their security. Otherwise they would rather align with Pakistan against us.

 

[IBRIS]

You gotta be kidding me? Maldives is an hundred percent Islamic nation..They don't allow non-muslims in their country. As a tourist, you are not allowed to carry any pictures of your faith. They also have worst form of blasphemy laws.

Not to worry about 300,000 maldivians mate. Offcource they would have to first obbide our secular Constitution and our Laws. K.P.S Gill is always there for our governments services, need i say more.

 

[integra]

keep on dreaming losers. You ain't getting a penny!

 

[idune]

Accelerating land increase in coastal areas

Bangladesh is rising in size contradicting forecasts that parts of this country will go under water due to global warming. Scientists at the Centre for Environment and Geographic Information Services (CEGIS) say that the country’s island has been increasing by 20 square kilometres (12.5 square miles) annually. They said that they have studied 32 years of satellite images and found that the country’s landmass has amplified by 20 square kilometres annually during that time. Data shows that the sediment travelling down the Ganges and the Brahmaputra rivers from the Himalayan watershed are creating new land as they wash into the Bay of Bengal.

A billion tonnes of sediment that the Ganges, the Brahmaputra and 200 other rivers bring from the Himalayas each year before crossing Bangladesh had caused the landmass to increase. A third of this sediment, makes it into the Bay of Bengal where new territory is forming from gradual deposition of the sediments. From this process in the next 50 years it could add up with the country gaining at least 1,000 square kilometers naturally.

The United Nations Intergovernmental Panel on Climate Change (IPCC) predicted earlier that Bangladesh will lose 17 per cent of its land by 2050 because of rising sea levels due to global warming. The IPCC sounded more pessimistic about the inevitability of this sea level rise as it concluded that the Himalayan glaciers would melt very fast and completely by 2010. But now IPCC is eating its own words and saying that their conclusion about Himalayan glacier completely melting, fairly soon, was based on wrong and unfounded premises. Calculations about the surety of the sea level rise and its implications for Bangladesh, therefore, have notably weakened. But satellite images dating back to 1973 and old maps earlier than that show some 1,000 square kilometres of land have risen from the sea.

The US and other developed countries, the main contributors to global warming which could affect Bangladesh, should help it out in projects planned to secure its coasts and population. Even if outside aid is not forthcoming, the government can proceed with dams and other structures planned to reclaim land from the sea on a sustainable basis. Bangladesh can take up such projects for implementation by mobilising its own resources and expertise. Reclaimed land mass can be used for human resettlement to ease population pressure on the main land as well as for productive purposes such as agriculture and related activities. Coastal areas – specially the offshore islands – have great potential for tourism. Tourist resorts in the coastal islands – like in the Maldives – can attract tourists, foreign as well as local.

 

[idune]

Bangladesh dams to reclaim 600 square kms of land(

AFP) – Sep 5, 2010

DHAKA — Bangladesh plans to build a series of dams to reclaim 600 square kilometres (230 square miles) of land from the sea over the next five years, officials said Sunday.

The government has approved the ambitious project under which dams would be built in the Meghna estuary to connect islands and help deposit hundreds of millions of tonnes of sediment, project chief Hafizur Rahman said.

"The project would cost only 1.20 billion taka (18 million dollars). The dams will expedite sedimentations and manage the tidal system. They won't allow loss of any sediments to the sea," he told AFP.

"The whole process will reclaim at least 600 square kilometres of new land from the sea in just five years."

The mighty Ganges and the Brahmaputra rivers join in Bangladesh before flowing into the Bay of the Bengal.

Studies have found that the two rivers carry more than one billion tonnes of sediment a year.

Rahman said the dams would be designed so that small islands would become linked with the mainland as shallow areas in the estuary fill up with sediment.

A study by the Dutch-funded Institute of Water Modelling (IWM) has found that the damming process would not affect other parts of the coastline or aggravate erosion of the country's largest island, Bhola.

"We have done some water models of the project and found some 600 square kilometres of new land could be reclaimed without any side-effects," IWM principal researcher Jahirul Haq Khan told AFP.

The study has been verified by Dutch experts, he added.

Bangladesh reclaimed 1,000 square kilometres of new land in the Meghna estuary by building two dams in 1957 and 1964. Despite the success, the reclamation process was halted due to lack of donor financing.

The impoverished country has been one of the worse victims of climate change, with the UN's Intergovernmental Panel on Climate Change (IPCC) predicting that 17 percent of its land would go under a rising sea by 2050.

AFP: Bangladesh dams to reclaim 600 square kms of land

 

[idune]

Bangladesh growing in size by 12.5 sq miles a year
Staff Reporter

Bangladesh is increasing in size contradicting forecasts that the parts of the country will disappear under water due to global warming.

Scientists at the Centre for Environment and Geographic Information Services (CEGIS) say that the country’s landmass has increased by 20 square kilometres (12.5 square miles) annually.

They said that they have studied 32 years of satellite images and found that the country’s landmass has increased by 20 square kilometres annually during that time.

Data shows that the sediment travelling down the Ganges and the Brahmaputra rivers from the Himalayan watershed are creating new land as they wash into the Bay of Bengal, they said.

Mominul Haque Sarker, Head of the department at the CEGIS that looks at boundary changes, said a billion tonnes of sediment that the Ganges, the Brahmaputra and 200 other rivers bring from the Himalayas each year before crossing Bangladesh had caused the landmass to increase.

About a third of this sediment, he said, makes it into the Bay of Bengal, where new territory is forming, he said.

Sarkar said that in the next 50 years this could add up to the country gaining 1,000 square kilometres.

The United Nations Intergovernmental Panel on Climate Change (IPCC) has predicted that Bangladesh, criss-crossed by a network of more than 200 rivers, will lose 17 per cent of its land by 2050 because of rising sea levels due to global warming.

The Nobel Peace Prize-winning panel says 20 million Bangladeshis will become environmental refugees by 2050 and the country will lose some 30 percent of its food production.

Director of the US-based NASA Goddard Institute for Space Studies, professor James Hansen, paints an even grimmer picture, predicting the entire country could be under water by the end of the century.

But Sarker said that while rising sea levels and river erosion were both claiming land in Bangladesh, many climate experts had failed to take into account new land being formed from the river sediment.

“Satellite images dating back to 1973 and old maps earlier than that show some 1,000 square kilometres of land have risen from the sea,” Sarker said.

“A rise in sea level will offset this and slow the gains made by new territories, but there will still be an increase in land. We think that in the next 50 years we may get another 1,000 square kilometres of land.”

Mahfuzur Rahman, Head of Bangladesh Water Development Board’s Coastal Study and Survey Department, has also been analysing the buildup of land on the coast.

He said findings by the IPCC and other climate change scientists were too general and did not explore the benefits of land accretion.

“For almost a decade we have heard experts saying Bangladesh will be under water, but so far our data has shown nothing like this,” he said.

“Natural accretion has been going on here for hundreds of years along the estuaries and all our models show it will go on for decades or centuries into the future.”

Dams built along the country’s southern coast in the 1950s and 1960s had helped reclaim a lot of land and he believed with the use of new technology, Bangladesh could speed up the accretion process, he said.

“The land Bangladesh has lost so far has been caused by river erosion, which has always happened in this country. Natural accretion due to sedimentation and dams have more than compensated this loss,” Rahman said.

Bangladesh has built a series of dykes to prevent flooding.

“If we build more dams using superior technology, we may be able to reclaim 4,000 to 5,000 square kilometres in the near future,” Rahman said.

Web Page Under Construction

 

[Maira La]

I'm in favor of slaves moving in only. Others make me feel insecure, their loyalty lies to the Chinese. They should not be allowed to cross the fence and take pictures of our land of the poorest.

Btw, doesn't india have long low-lying coastlines too? No reason for you to become so happy suddenly!

 

[Roybot]

Btw, doesn't india have long low-lying coastlines too? No reason for you to become so happy suddenly!

Not as much as Bangladesh. Can't believe some people are making mockery of this serious issue though.

Either case, this situation wouldn't arise for another 100 years or so. By that time Bangladesh would be developed and rich enough, both technologically and monetarily to deal with the situation. Heres an interesting paper regarding this isssue.


http://v3.weadapt.org/placemarks/files/225/golam_sarwar.pdf

Bangladesh is highly vulnerable to sea level rise, as it is a densely populated coastal country of smooth relief comprising broad and narrow ridges and depressions (Brammer et al., 1993). World Bank (2000) showed 10 cm, 25cm and 1 m rise in sea level by 2020, 2050 and 2100; affecting 2%, 4% and 17.5% of total land mass respectively (Table-2). Milliman et al. (1989; cited in Frihy, 2003) reported 1.0 cm per year sea level rise in Bangladesh.