Articles on vulnerable areas of Bangladesh:
Bangladesh is the most vulnerable nation to the adverse effects of climate change. The following articles discuss the negative impacts of climate change in Bangladesh.
Climate Change and Sundarban: An overview.
The Sundarbans is the largest mangrove forest in the world where about 300 species of trees and herbs and about 425 species of wildlife including the Royal Bengal Tiger exist.
The Intergovernmental Panel on Climate Change (IPCC) supposed that the state of tropical forest ecosystems is likely to get worse due to climate change. Bangladesh being in the tropical region, different physical effects of climate change including increased temperature and precipitation, increased salinity and extreme weather events such as floods, cyclones and droughts will have profound negative impacts on its forests.
Climate change due to global warming is predicted to cause an annual temperature rise of 0.4 degrees Celsius in Bangladesh and result in greater frequency and intensity of cyclonic storms. The sea level is also predicted to rise by 4 mm every year. These phenomena will result in an increase in salinity and a decrease in the sweet water flow in the Sundarbans.
The largest mangrove forest Sundarbans is contributing to the sustenance of the globe for it bears numerous trees and hence, it also maintains the safety of living beings in major part of Bangladesh. However, unprincipled human interventions are the major threat to nature.
Flowing water in the rivers, canals etc through and around the Sundarbans flush out saline water intrusion from the sea. Increase in salinity intrusion due to anticipated sea level rise is one of the major threats to the Sundari trees, which are already under threat due to increased salinity levels. Deforestation had previously caused major problems too. The government and various NGOs have now started to increase more plantation in the Sunderbans with the help of the local people as they were taught a harsh lesson and were served an eye- opener.
Effect of climate change in Sundarban.
The Sundarban forest lies in the vast delta on the Bay of Bengal formed by the super confluence of the Padma, Brahmaputra and Meghna rivers across southern Bangladesh. The seasonally flooded Sundarbans freshwater swamp forests lie inland from the mangrove forests on the coastal fringe. The word Sundarban means ‘beautiful forest’. It is a vast area in the Ganges delta comprising a network of 108 swampy, low-lying islands. The area is unique both ecologically, as the home of the man-eating Bengal tiger, and culturally – Hindus and Muslims both worship a deity called Bonobibi. The region’s low elevation above sea-level and proximity to the coast made it particularly vulnerable when Cyclone Aila struck in May 2009, destroying many of the inhabitants’ homes.
Due to the impacts of climate change an impact assessment shows the following areas are likely to be mostly affected.
Deer, hare, porcupine, arboreal monkey, rat and mice, etc. are purely herbivorous, seedivorous and fruigivorous. They all will face a shortage of food. Deer will be the worst sufferer due to food shortage and habitat loss. During high tide deer usually move to high lands in the forests. Carnivores like tigers, fishing cats, cevets, otters, etc. will face the similar problem: loss of habitat due to inundation and shortage of food due to lack of herbivores in the forest.Tigers are the world’s most endangered species and survive only in a few places including the Sundarbans of Bangladesh in very small number. Tiger is a good swimmer and may move from one place to another but the prevailing condition will not be favourable. Tigers of the Sundarbans usually move to higher places during high tide, but whither that when sea level rises?
Resident and migratory terrestrial birds of the Sundarbans and coastal areas will create excess pressure and ecological problems on the existing fauna and flora where they will fly. Aquatic birds like herons, gulls, terns, owls, nightgers, wagtails, pratincles snipes, sandpipers, finfoot, culew, whimbrels, spoonbils, wild ducks will also loss their habitats along the coastal belt.
Particularly the salt water crocodiles and five species of marine turtles, e.g. olive ridely, green hawksbill and loggerhead are endangered species. Crocodiles become more dominant because of expansion of habitat in the forests for preying on fishes and animals as food.
There are 375 species of birds, 55 species of mammals and 83 species of reptiles and amphibians in the Sundarbans. Besides, more than 150 species of fish, 50 species of shrimp and other invertebrates also live there. A change in climate will affect the distribution and living pattern of these due a to a change in their natural way of living.
The pnematophores (roots of mangrove plants) regularly go under water twice daily during high tide for 1-3 hours. In the inter-tidal period trees in mangrove and coastal mud flat areas use to respire by specially growing roots called pneumatophores. Each tree has thousands of such pnumatophores growing up about 10 cm to 1m high in the air and spreading 2-5m around the base. These air roots are smaller in golpata, hantal, goran, etc. and longer in sundri, gewa, amur, keora, etc. If the sea level rises from 0.5 to 1m the pneumatophores will remain under water permanently and trees will die due to problem of respiration and sand deposition.
Dhaka is one of the most populous megacities in the world. The area of Dhaka city is 1,353 square kilometers, with 14 million people. This sheer number of people living in the city means that the negative consequences of climate change are likely to be felt by a large number of people, especially the urban poor who live in flood-prone and water-logged areas. Experts working on the impact of climate change on Dhaka, predict that the city will be affected in two major ways: Floods and earthquake risks.
The earthquake disaster risk index has placed Dhaka among the 20 most vulnerable cities in the world. Geographically, Bangladesh is located close to the boundary of two active Plates: the Indian Plate in the West and Eurasian Plate in the East & North.
Thirty-five per cent of Dhaka, including middle & North part and Old Dhaka, is on standing on red soil and it is less susceptible to an earthquake, whereas the East and West areas are built on landfills, that are more susceptible to earthquake. Moreover, high urban growth rates and high urban densities have already made Dhaka more susceptible to human-induced environmental disasters.
Challenges to mitigate earthquake risks:
- Poorly engineered building construction, slum
- Densely built-up area with unplanned narrow lanes
- Violation of building code
- Loose soil & filled soil in few areas
- Shortage of evacuation space
- Unplanned public utilities
- Lack of disaster management equipments
- Ignorance of fire fighting
- Lack of data & education on earthquake
- Lack of community involvement
- Lack of disaster drill
- Unstable population growth
- Technological disadvantage
- Lack of training and awareness.
Floods and prolonged water logging in Dhaka city:
Floods occur most commonly when water from heavy rainfall, from melting ice and snow, or from a combination of these exceeds the carrying capacity of the river system. Every year near about one-fifth of Bangladesh undergoes flood during the monsoon season. Four major floods in last 20 years: in 1988, 1998, 2004 and 2007. Floods of 1998 and 2004 were worst in terms of inundation and duration of flood water in the city fringe areas.
Sylhet is considered one of the most charming and archaeologically rich regions in South Asia. Its boosting economy has contributed to the regional attractions of landscapes filled with fragrant orange and pineapple gardens, and breathtaking tea plantations. Sylhet has the area of 12,595.95 km2 where 9,807,000people live in the division as per 2011 population census. This beautiful city is geographically vulnerable to flash flood, water logging and earthquake. This division is also famous for wetland area, but due to climate change those wetland is facing untimely flood, heavy flood and drought also.
Syhlet is bordered by the Meghalaya, Assam and Tripura states of India to the north, east and south, so it is on threat of flash flood frequently. Especially in monsoon the possibility of flash flood increases drastically. Heavy rainfall on upper basin induces the flash flood in Syhlet. In other hand hill degradation, unplanned cultivation, deforestation increases the damage caused by flash flood in this region.
Challenges to mitigate:
- Unplanned upland cultivation
- Unplanned urbanization
- Population increase
- Hill degradation
Chittagong is 168 km2, the port city and only extensive hill area of Bangladesh. Chittagong has a tropical monsoon climate. Chittagong situated in the south-east part of Bangladesh. This area is well known for ethnic people resident. Chakma (48%) and Marma (28%) is the majority of ethnic minorities in Chittagong hill tracts. However, Chittagong also exposed to climate induces changes. There traditional cultivation “jhum” on the hill tract, for which they have to clean up the hill.
Land slide and Cyclone:
Chittagong is vulnerable to landslide and cyclone threat. For example, land-slide in 2007 recognized as climate induce disaster but flash flood and land slide mostly related to human made soil erosion and deforestation. Unplanned cultivation, hill degradation and deforestation are increasing the possibility of climate induce hazard. The high intensity cyclone of 1991 caused large-scale damage to coastal embankments along the Patenga area in Chittagong, destroyed runways of Chittagong airport, ceased port activities by sinking a number of ships in the Patenga channel and also in offshore dock.