Sea Level Rise

sea level is projected to rise 0.4 to 1.5 meters on the Bangladesh coast by 2100. Episodes of extremely high water driven by storms and tides, which today occur once a decade, will probably happen three to 15 times every year at the end of the century.

Rising sea levels create not only stress on the physical coastline, but also on coastal ecosystems. Saltwater intrusions can be contaminating freshwater aquifers, many of which sustain municipal and agricultural water supplies and natural ecosystems. As global temperatures continue to warm, sea level will keep rising for a long time because there is a substantial lag to reaching an equilibrium. The magnitude of the rise will depend strongly on the rate of future carbon dioxide emissions and future global warming, and the speed might increasingly depend on the rate of glacier and ice sheet melting (World Bank)

Threat to People's Existences

by: Warren Cornwall

A further rise in sea level is a threat to the existence of many people in Bangladesh. The relative sea level rises with double to quadruple speed: due to tectonic movements the ground level has been slightly falling, thus an average relative rise in sea levels by 4-8 millimetres per year has taken place. This equals a rise by 8-16 centimetres within 20 years. If the sea level rises by 45 centimetres, scientists expect a permanent loss of up to 15,600 square kilometres of land. If sea levels rise by one metre and no dyke enforcement measures are taken, 14,000 to 30,000 square kilometres will be permanently flooded, which means more than one fifth of Bangladesh will be under water

Additional to the permanent loss of land, an in-crease in floods is expected. Due to the rising sea level, large rivers could drain away slower from the delta systems. This feedback effect can cause penetration of heavier floods further inland. As sanitary conditions are insufficient, floods hold the threat of epidemics, such as Cholera. Wet areas, habitat of mosquitoes, will expand, therefore the risk of malaria infections will increase

Moreover, indirect effects of the rising sea level will increase the salt content of soils. Inview of Bangladesh’s already problematic food situation, the expected decrease of rice production as well as several hundred tons of vegetables, lentils, onions and other crops could be disastrous .Last but not least, valuable ecosystems would be lost. The Sundarbans, huge mangroves swamps along the coasts that are part of the United Nations world natural heritage, will be especially affected. They are the last retreat of the Bengal tiger. If the mangroves swamps disappear under water, the reserve of many hundreds of species, such as marine turtles, crocodiles and fresh- water dolphins, would be destroyed. 2 million Bangladeshis live directly on honey, shells, crabs, fish and wood of the Sundarbans. Furthermore, the mangroves swamps serve as natural storm barriers.

Water meets land in Bangladesh

Many Bangladeshis live on artificial islands called polders, behind walls built to protect the low-lying islands from floods. But the polders disrupt sediment deposits and face climate change pressures, and it's harder than ever to keep water out. Residents are considering new ways to protect the polders and their land.