Bangladesh facing Climate change
Bangladesh, except for the hilly regions in the northeast and southwest and terrace land in northwest and central zones, is one of the largest deltas in the world, formed by the dense network of the distributaries of the mighty rivers namely the Ganges, the Brahmaputra and the Meghna. The country is located between 20034’ to 26038’ north latitude and 88001’ to 92042’ east longitude. The total area is 147,570 sq. km. and consists mostly of low and flat land. A network of more than 230 major rivers with their tributaries and distributaries crisscross the country.
The land area of the country divided broadly into three categories i.e. floodplain (80%), Pleistocene terrace (8%), and tertiary hills (12%) based on its geological formation. The floodplain comprises of a succession of ridges (abandoned levees) and depressions (back swamps or old channels). Differences in the elevation between adjoining ridge tops and depressions range from less than 1 meter on tidal floodplains, 1 meter to 3 meters on the main rivers and estuarine floodplains, and up to 5 to 6 meters in the Sylhet basin in the northeast. Only in the extreme northwest do land elevations exceed 30 meters above mean sea level. The tertiary hill soil occupies the Chittagong hills in the southeast, and the low hills and hillocks of Sylhet in the northeast. The two major uplifted blocks (Pleistocene terrace) are known as Madhupur (in the central Bangladesh) and Barind tracts in the northwest.
The land type of the country has been classified according to depth in inundation with seasonality. All land types except highlands are exposed to monsoon flooding for part or whole of the year. Floodplains located in the northwestern, central, south central and northeastern regions are subject to regular flooding at different frequency and intensity while the coastal plain is subject to cyclones and storm surges, salinity intrusion and coastal inundation. Pleistocene terrace land is characterized by moisture stress while flash flood is common in the hilly areas and the piedmont plains in the northeast and northwestern parts of the country.
The economy of Bangladesh is primary dependent on agricultural activities. About 84 percent of the total population live in rural areas and are directly or indirectly engaged in a wide range of agriculture activities. Agriculture contributes about 32 percent to the country’s GDP, about 23 percent of which is contributed by the crop sector alone. About 63 percent of the labor forces are employed in agriculture with about 57 percent being employed in the crop sector. According to BBS (2006), about 44% of the country’s population lives below poverty level and 20% below hard-core poverty level. Over 80 million people are functionally illiterate, 90 million deprived of primary health care facilities and 40% never visited a medical graduate doctor. About 66% of the populations are engaged with agricultural activities (BBS, 2002). Moreover, 30 million people are unemployed in Bangladesh. The per capita income in Bangladesh is US$ 450 (World Bank, 2008). Annual economic growth rate is 5.6 (ADB 2006, Bangladesh Bureau of Statistics -BBS). The ranks below average per capita income for South Asian countries as well as the per capita income for low-income countries.
Bangladesh is a very densely populated country, where over 156 million (World Bank, 2008) people lives in an area of 147,570 square kilometers and with nearly three quarter of its population living in rural areas. The country has its identity as one of the highest population density country in the world and in terms of population it obtained the eighth position with a variety of culture, customs and religious believes. Of the total population, approximately 87% Muslim, 12% Hindus, 1% Buddhists and 0.03% are Christians by religion.
In 2009, Bangladesh ranked 136th in the Human Development Index (UNDP, 2009). Access to income and employment is limited, with a large service sector, a climate sensitive agriculture sector and industry. Access to drinking water is also insecure in some parts all year round due to saline intrusion in the coastal area, while in a large part of the country groundwater is contaminated with arsenic. The country also has to ensure health education service to its nationals to deliver a future generation that can cope effectively in tomorrow’s world. With 40% of the active workforce unemployed, livelihood options disappearing, and limited options to diversity earnings. The society has demonstrated its will and effort to respond to national emergencies, particularly those with regard to natural hazards like floods, tornado, landslides, cyclone, storm surge, cold spell, etc. However, frequent and uncertain weather conditions and extremes have eroded the household and community safety nets.
Climate Change and its consequences in Bangladesh
Bangladesh is already evidencing the adverse impacts of global warming and climate change. Summers are becoming hotter, monsoon irregular, untimely rainfall, heavy rainfall over short period causing water logging and landslides, very little rainfall in dry period, increased river flow and inundation during monsoon, increased frequency, intensity and recurrence of floods, crop damage due to flash floods and monsoon, crop failure due to drought, prolonged cold spell, salinity intrusion along the coast leading to scarcity of potable water and redundancy of prevailing crop practices, coastal erosion, river bank erosion, deaths due to extreme heat and extreme cold, increasing mortality, morbidity, prevalence and outbreak of dengue, malaria and diarrhea etc. Climate change impacts are already adding significant stress to our physical and environmental resources, our human ability and economic activities. Impacts of observed changes are felt most in the following sectors: Water resources, coastal resources, agriculture, health, livelihoods, food security and habitat/settlement security.
According to IPCC in their Fourth Assessment Report (IPCC, 2007), the following changes have been observed in climate trends, variability and extreme events:
- Average temperature has registered an increasing trend of about 10C in May and 0.50C in November during the 14 year period from 1985-1998.
- The annual mean rainfall exhibits trends in Bangladesh. Decadal rain anomalies are above long term average since 1960s.
- Serious and recurring floods have taken place during 2002, 2003, and 2004. Cyclones originating from the Bay of Bengal have been noted to decrease since 1970 but the intensity has increased.
- Frequency of monsoon depressions and cyclones formation in Bay of Bengal has decreased.
- Water shortages has been attributed to rapid urbanization and industrialization, population growth, and inefficient water use, which are aggravated by changing climate and its adverse impacts on demand, supply and water quality.
- Salt water from the Bay of Bengal is reported to have penetrated 100 km or more inland along tributary channels during the dry season.
- The precipitation decline and droughts has resulted in the drying up of wetlands and severe degradation of eco-system.