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Bangladesh, Pacific Islands, Torres Strait

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Bangladesh, Pacific Islands, Torres Strait

Bangladesh

Finally, let's visit the country of Bangladesh where a large swath of the populous coastal lies very close to sea level. In fact, a one-meter rise in sea level would inundate 30,000 km2 and displace 20 million people. This area is already extremely prone to flooding from cyclones and this danger will increase with sea level rise.

Bangladesh Flooding

The following video provides a stark picture of flooding in Bangladesh in 2004.

Video: Complete Bangladesh Movie (3:33). This video is not narrated.

Complete Bangladesh Movie
Click here for a transcript

Bangladesh 2004

July to September

70% of the country is less than 1m above sea level. The three main rivers are, Brahmaputra, Meghna, and Ganges. It is the world’s most densely populated country with 150 million people. Bangladesh has one of the world mega deltas, 52 rivers emptying to the Bay of Bengal. Every year Bangladesh, suffers a monsoon and vast amounts of snow melt.

The Causes - Long Term

Global Warming

The global warming effect, causes more severe weather. In the example of Bangladesh it created more violent monsoons and snow melt, adding to flooding.

Urbanisation

Huge cities are stopping rain reach the earth, making faster run-off and more chance of flooding. Poorly maintained river and lake embankments made the maximum river discharge very low, and increasing the chance of floods.

The Causes - Short Term

Spring Snow Melt

Each year the snow melt puts the rivers to breaking point. In 2004, this combined with other factors made a huge flood.

Deforestation

Deforestation in Bangladesh has stopped interception, meaning that the rain gets to the rivers faster, increasing the chance of flooding. It was monsoon season, with the highest rainfall for 50 years, leaving the ground saturated.

Burst Dam

A dam at Tsatitsu Lake in the Himalayan kingdom of Bhutan had burst, spilling water into tributaries of the Brahmaputra.

The Events

Around 20 million families in need of emergency relief making six million people live in makeshift shelters, their homes destroyed. More than 2,000,000 acres of farming land was submerged and countless crops ruined. 500,000 cattle and poultry were killed. About two-thirds of the low-lying nation is under water, polluted with sewage, exposing 5 million people to water-born diseases. Damaged transport blocked aid getting to people in rural areas, so the death toll rose. The flooding washed away entire rice plains, leaving millions without food. These millions then having to share the little aid that reached them, causing national, malnutrition and starvation. The damage is thought to be in excess of $2.2 billion. The death toll was estimated at about 800. Although some people were not found, or not reported dead.

Responses - Short Term

Boats and emergency services sent to help the stranded and drowning… emergency food, medicine, and tents were sent to those who were not stranded. Aid from other countries and international help were sent. Repair to homes and to the sewage works started as soon as possible.

Responses - Long Term

New laws are in place to reduce deforestation. 350km of embankment seven meters high have been built. Seven large dams are under construction to store excess water. 5000 flood shelters built to hold the entire population. The Bangladesh floods of 2004 was a world catastrophe. Many died and many more became homeless or lost their livelihoods. Bangladesh has learnt from the floods, and are working towards a safer, more secure country.

Credits: Christopher Cooper

Pacific Islands

A dire picture also emerges in small island nations in the western Pacific, including Kiribati, Tuvalu and the Marshall Islands where sea level rise over the next century could cause these nations to completely disappear. In fact, the President of the nation of Kiribati has publicly stated that the 100,000 citizens in his country may need to be relocated as a result of climate change and sea level rise. In Tuvalu, large tides occurring in January, February, and March, and August, September, and October, known as King Tides, flood some areas of the main island and capital city Funafuti. Before sea level rise was a problem, these tides did not cause extensive flooding. Now, they are responsible for salinization of the soil which makes it infertile and for spreading diseases because of the leaking septic tanks, as well as loss of inhabitable land.

Like in the Torres Straits, inhabitants on many low-level islands in the Pacific are building sea walls to keep the rising seas out. However, in many places, the walls are built out of coral often obtained from fragile offshore reefs that themselves offer some protection from the rising seas.

Pacific Islands

Torres Strait

One hundred and fifty islands lie between Cape York Australia and Papua New Guinea, 17 of the islands are permanently inhabited by about 7000 people belonging to indigenous populations related to the Aboriginal peoples of mainland Australia. With an average elevation close to sea level and a large tidal range (spring tide is about 10 feet), the islands are very prone to the effects of sea level rise. Trends suggest that the island may be characterized by a slightly higher rate of sea level rise than the global average. Even if the islands remain emergent, as sea level rises, they will still be far more prone to the impact of extreme events such as tropical cyclones as well as regular high tides. With very limited resources, the islands have had a piecemeal response to rising sea levels by building sea walls along the low-lying area. Unfortunately, these walls are in dire need of repair and reinforcement. Torres Islanders have pleaded with the Australian government to help rebuild and fortify the sea walls to protect the vulnerable areas. In August 2011, the government appropriated $22 million to build the wall, however, they backtracked four months later and, thus, the plight of the islanders remains in jeopardy.

Torres Strait

So, a final word. As you can imagine, Hurricane Sandy has reinvigorated the call for flood barriers and sea walls at the entrance to the New York City harbor. Such structures are very expensive but would have saved an enormous amount of destruction from the storm. This is not the only city where flood barriers will be needed in the future as the video below describes graphically.

Video: RockWorks: EarthApps - Sea Level Rise Simulations (3:01)

​​RockWorks: EarthApps - Sea Level Rise Simulations
Click here for a transcript of the Sea Level Rise Simulations video.
The following simulations depict 61 meter increases in sea level over the next 10 years. This 10-year time period was chosen for dramatic purposes, completely unrelated to scientific observations. Instead, these simulations, coupled with ominous music and low-frequency narration, definitively answer the biggest challenge currently facing mankind. In this simulation, the city of San Francisco, California is virtually destroyed. One of the only features left above water within London would be the clock at the top of Big Ben. The Opera House in Sydney would be completely submerged. Property values within Hong Kong would continue to rise. What can you do to prepare for these changes? Take your family and loved ones and head to high ground. Wait, first buy Rockware products, and then head to high ground.