This paper has prepared through a comprehensive consultation process under secondary data sources. So usually information was collected from documents available mainly in electronic database. Some documents were retrieved from the database (websites) of several national, and international agencies were browsed.
Climate Change and the Experience of Bangladesh Bangladesh is affecting seriously by environmental degradation due to global climate change, ozone layer depletion. The country has already begun to feel the effects of climate change as flood periods have become. longer and the cyclones, droughts and earth quakes that hit the country cause greater devastation and adversely affecting the country's agriculture and land, and challenging water resources, food, health, energy etc.
Historical trend shows that the country experienced 30 damaging floods between 1954 and 1998, of which 12 were severe and 5 were catastrophic. The occurrence of flood experienced by Bangladesh is deemed to be the worst in the globe, both in terms of duration and damage. Abnormal floods submerge about 60 percent of the land, damage crops, property; disrupt economic activities and cause diseases and loss of life beyond all proportion (Nasreen, 2004). According to government statistics, 298 people died and 10,211,780 people were badly affected by it. 56,967 houses were damaged by the floods up to 13 August 2007. In 2004, around 30 million Bangladeshis were affected by flood (Biswas, 2013). Between 1991 and 2000, 93 major disasters were recorded in Bangladesh, resulting in nearly 200,000 deaths and causing US $ 5.9 billion in damages with high losses in agriculture and infrastructure. Because of sea level rise coastal Bangladesh has already experienced the worst impacts especially in terms of coastal inundation and erosion, saline intrusion, deforestation, loss of biodiversity and agriculture, and large scale migration. About 830,000 million hectares of arable land is affected by varying degrees of soil salinity. During the period 1973–1987, about 2.18 million tons of rice was damaged due to drought and 2.38 million tons due to flood. However drought affected annually about 2.32 million hectares and 1.2 million hectares of cropped land during the Summer (November to June) and Winter (July to October) seasons respectively, while soil salinity, water logging and acidification affect 3.05 million hectares, 0.7 million hectares and 0.6 million hectare of crop land, respectively in the country (Government of the People’s Republic of Bangladesh. Department of Environment, 2007). Experts from home and abroad observed that alarming decrease in water flow down the rivers caused high salinity in both water and soil of Sundarban, causing a massive change in faunal composition of the forest. Sundarban, which lies across the outer deltas of the Ganges, Brahmaputra and Meghna rivers, is the largest mangrove forest in the world. The number of timber producing big trees such as Sundari is decreasing at the proportionate rate at the increase of salinity.
Evaluating the changing climate pattern in Bangladesh: An assessment It is important to evaluate how climate has varied and changed in the past. The monthly mean historical rainfall and temperature data can be mapped to show the baseline climate and seasonality by month, for specific years, and for rainfall and temperature. In the following charts show mean historical monthly temperature and rainfall for Bangladesh during the time period 1960 to 1990 and 1990 to 2009 respectively 30 and 19 years. The dataset has collected from the Climate Change Knowledge Portal of World Bank. This paper here firstly has comparatively assessed the average temperature of these two sessions and secondly rainfall.
From above assessment, we can say that temperature is increasing in both monsoon and winter period and rainfall indicate more rains during monsoon and lesser during dry periods. It is known that very small changes in the temperature, rainfall or sea level rise can lead to severe consequences for our country like Bangladesh and already has stressed environmentally, socially and economically. Also, the variations can be quite significant when downscaled for a location. In addition, there may be more than one impact at any given period which can lead to grave circumstances. Further, climate change-induced impacts may trigger a chain of consequences due to non-climatic activities and their outcomes. In this phase the study has mentioned the most profound impacts of climate change in Bangladesh which are predicted by experts. 1. Rising Sea Level 2. Disappearing Under the Waves 3. Increasing Flood Risk and Salinity 4. Agricultural Production 5. Damaging Availability of Fish Supply 6. Prevalence of Diseases.
What should government do? To understand climate impacts and hazards, some potential queries need to be answered. These are: Which types of hazards may become more frequent and intense? What will their altitude of enormity? Which locations are most vulnerable? What is the feasible time of occurring hazards? What will be the possible impacts of its aftermath?