Natural Disaster Final

8/13/2019 Natural Disaster Final

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INDEPENDENT UNIVERSITY BANGLADESH

Assignment on

Natural disaster and its impact on Bangladesh

Introduction to Environmental ScienceENV: 101

Section: 01

Submitted To:Ms. Shahima IslamLecturer,School of Environmental Science andManagement

Submitted By:

MASUD PARVEZ RANAID: 1030155MD. NAHID PARVEZID: 1130442MD. MARUF CHOWDHURYID: 1020758ABDUL HAZIID: 1130434



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Natural disaster and its impact on Bangladesh

Introduction: Natural disasters are defined as events (shocks) that are triggered by natural phenomena ornatural hazards (such as earthquakes, hurricanes, floods). Natural disasters have a huge impacton social and economic welfare. Policies to manage them need to be integrated and wellgrounded to the specificities of natural hazards as well as local capacities in terms of fiscal,administrative and economic capabilities. Bangladesh is most vulnerable to several naturaldisasters and every year natural calamities upset people's lives in some part of the country. Themajor disasters concerned here are the occurrences of flood, cyclone and storm surge, flashflood, drought, tornado, riverbank erosion, and landslide. These extreme natural events aretermed disasters when they adversely affect the whole environment, including human beings,their shelters, or the resources essential for their livelihoods. The geographical setting ofBangladesh makes the country vulnerable to natural disasters. The mountains and hills borderingalmost three-fourths of the country, along with the funnel shaped Bay of Bengal in the south,

have made the country a meeting place of life-giving monsoon rains, but also makes it subjectedto the catastrophic ravages of natural disasters. Its physiography and river morphology alsocontribute to recurring disasters. Abnormal rainfall and earthquakes in the adjacent Himalayanrange add to the disaster situation. Effects of El-Nino-Southern Oscillation (ENSO) and theapprehended climatic change have a great impact on the overall future disaster scenarios. SinceBangladesh is a disaster prone country, it is subject to colossal damages to life and propertyalmost every year. The different types of disasters, and their impact on the affected areas can broadly be summarized as in the accompanying Table 3.5.1. uproot trees, telephone, telegraphand electricity lines, destroy bridges, culverts, and houses, kill people and domestic animals,leaving serious and adverse effects on the economy as well as on the whole environment.Although this country with monsoon climate has enough rain, droughts frequently take a

significant portion out of the agricultural economy of Bangladesh, and cause hunger, instability,and insecurity. The northwestern part of the country is vulnerable to drought. Disastrous erosionsare mainly associated with the major river systems of the country and are seen along these river banks i.e., the Brahmaputra- Jamuna, the Ganges-Padma, the Lower Meghna, and other rivers.The effects of a natural disaster, or a combination of more than one natural disaster may be directloss of life, and certainly damage to physical properties. This requires large resources for disastermanagement including mitigation, recovery and preparedness. Therefore, the consequences ofthese natural hazards and the resulting environmental degradation pose a serious threat to theeconomic development of the country. The situation calls for an effective disaster warning anddissemination system. A timely and accurate alert system about impending disasters will helpreduce the loss of life and property. Natural disasters cannot be prevented, but the damage

can be mitigated with adequate planning and adaptation. The impacts of these disasters vary withtheir type and magnitude. They also critically depend on institutional strength and response bythe different agencies that usually take measures to mitigate and eventually overcome the losses,such as the government and other civil service organizations.



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Table 3.5.1 Types of Disasters and their Impacts in Specific Disaster Prone Areas



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Floods:Many parts of Bangladesh are flooded every year as a result of rainfall and the overflow of river banks; the local population has adapted its livelihood strategies and agricultural practicesaccordingly. However, natural calamities such as major floods, tropical cyclones, tornadoes andtidal bores occur almost every year, varying in magnitude and intensity. Most parts of

Bangladesh are less than 12 metres above sea level, and it has been calculated that about 50 percent of the land would be flooded if the sea level were to rise by just one meter. Floods suchas flash floods, monsoon floods and localized floods after cyclones, or when embankments are breached, have a severe impact on people’s lives and the wider economy. In September 1998,Bangladesh suffered the most severe flooding in modern world history:two thirds of the country was underwater, there were 1500 deaths and 30 million people were lefthomeless. The floods caused severe damage to road infrastructure, standing crops and livelihoodassets such as agricultural equipment and inputs, productive assets and livestock. The total lossto the economy was estimated at US$1200 million. The severity of the 1998 floods is explained by the unusually high monsoon rains that year, combined with a similarly high amount of meltwater from the Himalayas. There was also serious forest and soil degradation throughout the

watershed catchment area (upstream and downstream), which increased the water run-off. Due tohigh population pressure and skewed landownership patterns, farming and settlements areincreasingly pushed onto marginal land in areas at high risk of flooding. As a result, largenumbers of people, especially the poor, are almost continuously exposed to flood related riskssuch as loss of life, crop damage, loss of assets (e.g. livestock and fishing equipment) anddisruption to their livelihoods in general. When flooding occurs, vulnerable groups often losetheir crops and assets, and may not be able to meet their daily needs or pay their loans. As aconsequence, they are then forced to sell or lease out their land, resulting in changes in landtenure arrangements. One important example of such marginal, flood-prone areas is the highlyunstable chars, the temporary lands within and adjoining the major rivers. Because these charsmay be ‘new’ land emerging as a result of sand deposition, landownership in these areas is at

times highly disputed.

Photo -Flood is a recurring phenomena Photo -City roads under floodwater



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Photo - Dhaka under floodwater

Cyclones:Cyclones are very strong winds combined with intense rainfall. The 1991 Gorky Cycloneclaimed 120 000 lives in Bangladesh and caused serious damage to livelihoods, assets andcommunity infrastructure. The recent 2008 super cyclone, Sidr, affected more than nine million people in the southern districts of the country, and caused serious damage to housing,infrastructure, assets and standing crops. Compared to the Gorky disaster the number of deathswas considerably lower: more effective early warning systems were now in place and cyclone

shelters were more widely available. However, the number of cyclone shelters is insufficient tocater for the number of people who need them, and usually the poorest sectors of the populationliving in high risk areas are too far from such shelters. Like floods, cyclones can have adevastating impact on people’s livelihoods, as a result of loss of crops, livestock and other assets.The land they used to farm or live on may disappear completely, or be damaged to the extent thatit is no longer suitable for cultivation. Families also run the risk of losing their title deeds andmay no longer be able to prove their ownership of the land. For example, in Sri Lanka after the2003 Tsunami, many families lost their title deeds; as some local government offices were alsoseriously damaged, there were no land records at all.



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Photo -Storm path Photo -(A damaged village in Bangladesh, afterthe storm had struck)

Photo - Super Cyclonic Storm .

River erosion:Whereas floods and cyclones are recurrent, river erosion is a serious, continuous threat faced by people living near rivers and coastal areas. Given Bangladesh’s high population density andunequal land distribution, many of the rural poor are forced to live in flood- and erosion-prone

areas along the rivers and the coast. It has been estimated that at least 20000 families are madehomeless because of river bank erosion every year. They are forced to migrate within theirlocality or to urban areas, joining the growing number of the urban poor. River erosion alsoaffects local community infrastructure such as schools and colleges, mosques, markets, localclinics, hospitals and ports. For example, Chandpur – the biggest river port in the country and animportant economic hub – has been severely affected by river erosion. Considerable funds have been invested to protect Chandpur from further erosion, but to little effect, partly because of alack of strategic planning. When river erosion occurs quickly and suddenly, vulnerable groups



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may lose everything overnight. In other instances, river erosion is more gradual and people havemore time to move their assets to a safer place. However, loss of cultivatable land and theirhomesteads is often inevitable. The magnitude of land lost to river erosion can be large and issometimes referred to as a ‘silent tsunami’. National figures on the number of people affected,the areas of land eroded, and the damage caused by river erosion, are daunting. Between 1981

and 1992, 728 000 people were displaced by river erosion, an average of 64 000 each year. In thechar areas, an estimated 462 000 people were displaced during this 11-year period, amounting toaround 12 percent of the char area population8. Recent national figures are even higher,indicating that more than 250 000 people are the victims of land erosion every year, and annualeconomic losses are estimated at TK 1000 crore9. Many of those who lose their land have noother option except to move to major urban centers such as Dhaka. Some find themselves livingtheir lives on the street as pavement dwellers: even a shack in a slum is beyond their reach10.According to the Centre for Environmental and Geographic Information Services (CEGIS), 155280 hectares of land were eroded between 1973 and 2007. Moreover, CEGIS forecasts that forthe next few years, about 29 000 people per year living along the major rivers will lose theirhomes and land. River erosion has always been common in Bangladesh, but its increasing

frequency and intensity in recent years is causing concern. Reasons for this trend include climatechange, deforestation in the Indian and Nepalese Himalayas, the silting of river beds coupledwith the absence of adequate and appropriate river management, and a growing population.Increasing population density means that more people are shifting their lives towards the river banks, making them vulnerable to erosion and flood damage. River erosion also affects national borders.

Photo -River bank erosion Bangladesh has been losing land to India and Myanmar as a result of border-river erosion. Over

time the border rivers Surma and Kushiara have changed direction, shifting the original border sothat it is deeper inside Bangladeshi territory, resulting in a huge loss of land to India. Accordingto a government estimate, the country has already lost nearly 15 000 hectares of land, caused byerosion in the 15 rivers that are shared with India and Myanmar. The country's borders, definedin 1974 by the Indira–Mujib border treaty, have now changed considerably, given that the Indiansides of the rivers are better protected against erosion.



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Climate change and natural disasters:Bangladesh is among the most disaster-prone countries in the world and has already suffered 170large-scale disasters between 1970 and 1998. The frequency, intensity and scale of floods haveincreased, with eight major floods occurring between 1974 and 2004. Given current trends inclimate change, and other triggers such as man-made disasters (e.g. deforestation, soil erosion), itis expected that the scale, intensity and frequency of disasters will also increase. The populationof Bangladesh will need to cope with the impact of floods, droughts, cyclones and other extremetemperatures on a more regular basis. These will not only affect the population and its



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livelihoods but also seriously affect infrastructure, such as port facilities and coastalembankments and structures. Natural disasters will also destroy quality farm lands and existingirrigation and drainage schemes, disrupt mangroves, fisheries and bird habitats, accelerate coastaland river erosion, increase salt water intrusion into ground water, rivers, agricultural, and coastalforestlands, and affect cyclone and storm surge protection measures in coastal areas.

Abnormal Rainfall, Hailstorms, and

Lightning:Monsoon depressions that form in the Bay of Bengal move landward, and cause monsoon rain to be spread widely throughout the country. The mean annual rainfall in Bangladesh varies fromabout 1400 mm. in the western part of the country, to almost 5000 mm. in the northeast region.There are wide seasonal fluctuations, with about 90 per cent of the rainfall occurring during thefour months of the monsoon period (June - September). Monsoon depressions that form in theBay of Bengal move landward, and cause monsoon rain to be spread widely throughout thecountry. Based on the area of formation, structure, intensity, and frequency of the monsoondepressions, the total rainfall during the monsoon period can be predicted. In spite of an overall

abundance of rainfall during monsoon, at times serious rainfall shortage leads to droughts. It isnot unusual for regions in Bangladesh to experience inadequate rainfall during the monsoon,while little rain during the dry season (October-March) is quite common, too. A number ofconstraints are inherent in the monsoon rainfall, and climatic pattern. In addition, uncertainty in patterns of pre-monsoon showers, lightning, and hail cause a tremendous impact on human life,and agricultural production. The month-to-month and year-to-year variations in the atmospheric parameters like rainfall, temperature, humidity, etc., cause substantial variations in crop yields.Therefore, in Bangladesh the patterns of life, and cultivation practices have traditionally beenadapted to seasonal variability in climatic characteristics.

IMPACT OF NATURAL DISASTERS:

Natural disasters have a tremendous impact on the overall economy of the country. Apart fromthe instant impacts, natural disasters can also leave long-term impacts. Almost every year due tonatural disasters and climatic hazards, Bangladesh is subject to colossal loss of life and damageof property. All the national planning efforts for development are disrupted by these calamitiesthat leave behind damaged infrastructure facilities, physical assets and land. The human sufferinggoes beyond description. The impact of natural disasters not only varies with their type andmagnitude, but also critically depends on institutional strength and response to disasters bydifferent branches of the government, as well as community-based organizations. For example,the intensities of the 1991 and 1997 cyclones were of the same magnitude. In the 1991 cyclone,more than 13.7 million people were affected, approximately 138,882 people died, and 139,058 people were injured; and the total loss of livestock and poultry was about one million. On the

other hand, the number of human deaths were only 134 from the cyclone in 1997, and 0.4 million people were affected. Loss minimization was only possible due to accurate and timelyforecasting, adequate proper warning dissemination, social mobilization, proper coordination bythe government, and other institutional backup. The effects of the devastating flood of 1988 wereenormous. According to the World Bank, 45 million people were affected - with 1600 deathsdirectly attributed to it, and another 735 deaths occurred subsequently as a result of diarrhealdiseases. Damage to summer rice crops was estimated at about 1.6 million tons, and loss of physical and economic infrastructure was extensive. About 2,500 km of flood control

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