Examining The Flooding Effects In Gambia Environmental Sciences Essay

Examining The Flooding set up In Gambia Environmental Sciences EssayFloods stomach been a major lifelike fortuity, affecting the Gambia over the exit decade. It effects has been a ca single-valued function for concern, because the Gambia is placed in the scummy lying coast and it has a execrable competency in resolving the problems on overindulges. As a result of the salary join on slope ocean directs, along with excess rainf altogether and steep tides, the Gambias river reaches its runoff stage, cause soakering and inundation.According to UNFCCC (2007), the Gambia is ploughshare of the worlds most endangered countries, that be given over to the effects of ocean direct rise and the countrys has a few resources to crop the finds, it poses for the future. The aim of this report is to to a subvert placestand the impacts of sea level rise on river engorge and also, to understand its consequences for the overindulge endangerment vigilance in Gambia.geograp hics and DemographyThe Gambia, being the sm whollyest country in the Afri open fire continent, has an ara of 11,000 km (NEA, 2010). Studies from the UNEP(no date) claim that, about one third of its surface area is cover by the Gambias river with marsh flat coats along its banks. Its river originates from the Futa Djallon bluelands in Guinea, bisecting the country into a sign strip of land, approximately 400 km long and 30 km wide on both sides of Gambia (see chassis 1). Gambia is bordered on all sides, by the Republic of Senegal and on the west, by the Atlantic Ocean (GOTG, 2008). plan 1 comprise of the Gambia ( Jaiteh and Saho, 2006)Climate and communityThe Gambias climate is k forthwithn to be subtropical, with dry seasons from November to May, and wet seasons from June to October. Rainfalls and tides are known to be the key components that twist the rivers flows, as the rainfall ranges from 850-1,200 mm per annum (NEA,2010). However, over the past decades, in that locati on has been big outbreaks of drought cod to low rainfall patterns. As a result, relatively little vegetation cover, has increased the exposure of severe runs, because of inadequate semipermeable surfaces. During the wet seasons, the excess rainfalls, is the period when the overflow of the river banks and into the flood outplains, reaches its peak (GOTG, 2008).The Gambias population is now estimated at 1.36 million (Jaiteh and Saho, 2006) with a density of over 130 persons/km2 (UNDP, 2000). A study by Columbia University(2007) claim that almost 62% of the population, residing right(prenominal) the 10 meter elevation of the coastal areas, are at guess of coastal fill, and they are susceptible to the effects from sea level rise(see Figure 2). Also 14% of the population, living in the upper river division and the 13% of the population living in the Central river division are those, under greatest threat of river inundate.Figure 2 Population density map(Columbia Univeristy,200 7)The countrys morphology is made up of its river, which divides the country into two separate forms of a plateau. The lower valley is up to a total land area of 39 percent and its swamps are prone to floods, thus it is only 2 km away from the river ( Jaiteh, 2008).Jaiteh (2008) states that, the countrys highest land circus tents are in the east of the country, although they are not above 60 meters. The areas shaded in green are those that are to a greater extent prone to river floods, hence it is less than ten meters above cerebrate sea level (see Figure 3). Correspondingly, the river flow is up to 30 percent below 10 meters above connote sea level and up to 20 percent during flood seasons (NEA, 2010)Figure 3 Elevation Map of The Gambia (Jaiteh, 2003)Flooding in The GambiaFlooding has been the most common hazard, which unnatural great deal throughout the world. Annually, 75million people are affected by flood cogitate disasters (Coppola,2011). In Gambia, the national disaste r prudence agency (2008-2011) reported that between 2002 and 2006, there have been 65 flood gists. Human activities add to the vulner might of flood prone areas, especially in the north bank division, disforestation and poor farming tends to reduce the soils ability to hold the flood irrigates, and this causes more than runoffs and erosion (NEA, 2010).Floods can be considered as natural occurrence, rather than pin it on the effects from climate change. Knuckman (2011) states that, as the catchment reaches its excess wet system levels, its loses its ability to restore this excess piss and then flooding arises. In appendix to that, Cooper and Pilkey (2004) believe that other factor listed below also contributes to the factors that induction floods. There are three main factors that influence river floods areocean level Forcing Due to the high rations between the width and length of the river estuary, Jaiteh and Sarr (2011) have claimed that, sea level rise go out increase tow ards the inner part of the river estuary and this applies to the river Gambia due to it land along the river is flat.Wind forcing The go pressure has a huge impact on the irrigate level. Reports from the Gambias meteorology office die that, during the last 10 years, there has been a 25cm difference in the water levels between the rainy and the dry season, due to shifts of wind speed. During the rainy season, the forces of the wind has a higher load over the rivers surfaceTributary forcing The rivers destine discharge ranges from 460-90 m3 (Leseck et al, 1980)and the impacts of the severe stream flows affects the rivers tributaries, increasing pressure on the rivers pressure.. place evaporation is expected to increase, and this can place additional constraints on focusing rules of an upriver reservoir in the country. Also, integrated Water Resources caution (IWRM) institutions faces problems associated with the water floods from sea level rise, as drainage congestion increases the height of flood levels.During wet seasons, when excess precipitation triggers the river to reach its flood stage, causing the fill up water to flow to the flood plains and unto the land (GOTG, 2008). In1999 and 2003, there was a unsafe flood event that occurred in Upper River and Central River Regions, affecting 13.1% of the countrys population ( matter disaster recognizement agency2008-2011). The Gambias has developed a national disaster care agency in 1996, as a response strategy, to provide arrest assistance rescue, relief and precautionary operations, for all the disasters in the country. Under this agency, there has been a framework called the strategic action plan, which provides a pathway on what actions and mechanisms to be undertaken for an effective disaster dole outment for the Gambia.For instance, in terms of precautionary strategies of floods, this management agency provides sand bags, as flood proofing against the flood water levels during the rainy season s. Although this process has not been effective, because during the recent floods (1999 and 2003), the forces of the flood waters has exceeded the substance of those existing sand bags over the recent years (GOTG, 2008).A geek study event July 2010 floodings (Jaiteh and sarr 2011)In September 2010, there was an extreme flood event from heavy rainfalls affecting 1,000 and 790 people were displaced. The field of study Red hybridise provided financial support on those affected, whilst Red Crescent societies, were prudent for the destiny rescue and rehabilitation aid (DREF, 2010)Jallow et al(1996) carried out a question of a one meter sea level rise scenario on the coastal zone. He concluded that, 1m rise in sea level due to flooding would lead to a total land loss of 92 km in Banjul, because its elevation , and Banjul is built on a low lying sand spit (see Figure 4). An estimated total follow of 217 million US Dollars, worth of land could be lost, including the mangroves on St. Marys Island, and along the river banks in the north bank divisions (National Climate Committee Banjul, 2003).Figure 4 Areas susceptible of flooding with a 1 meter sea level rise (GOTG, 2007)The Gambia disposal has also formulated a national adaptation chopine of action on (NAPA) on climate change, which is under the tribunal of the UNFCCC. This framework was signed by the Gambia in June 2001, as a intend of developing adaptations to climate change and also, to attain limp schemes for natural disasters much(prenominal) as floods (Jaiteh and Sarr, 2011).Currently, there have been no existing engineering flood defenses in place, against the prevention of floods in the Gambia. According to executive director of the National disaster management agency, claimed that inadequate resources and low funding has been the countrys main stumbling block, in generating effective flood nourishion structures such as embankments and dykes. Mr Khan, further went on to say that, there has been ten happening action plans, funded by the gentleman Bank in 1998 to enhance sustainable actions for their flood risk management strategy.Effects of sea level rising in GambiaThe sea level is rising due to an increased temperature from the atmosphere which causes thermal expansions in the oceans and the resolve of the ice caps( Gehrels and Long, 2008). This outcome increases the water level of the sea to rise.Reports from IPCCC(2007) claimed, that global sea level is likely to increase by 18 cm to 59 cm by 2100. In Gambia, it is believed that the sea levels could rise by 15cm to 95 cm by 2100 (UNFCCC,2007). This involves that, if global warming is not monitored , the challenges of head with extreme flood will perpetuate, which will cause future constraints to the Gambias disaster management agency. This outcome of global warming, threatens the risk of potential rivers flooding at an alarming rate in the future if there is not step-down in greenhouse gases.Rising sea levels, inu ndates the coastal zone, due to its low lying feature the Capital city Banjul is vulnerable to flooding it is less than one meter above mean sea level (see figure 3). It is believed that the relationship between the effects of sea level rise, is caused by the changing climate conditions and the natural occurrence of the river (Hunt,2000). For instance, at the rivers estuary, the rising water level from the sea, with heavy precipitation during the wet season increase the risks of flooding in the rivers floodplains (National hazard Management histrionics, 2008-2011). On the other hand, Jallow et al (1996) reveals that, high tides on the river estuaries, influenced by the westerly winds has also been a major factor why the river Gambia floods. Unfortunately, the tide record recorder has not been in social occasion over the past years, for further analysis (see Table 1)Table 1 Tidal recorder table Water levels from tide records taken in Banjul, from 1979 to 1993(Jallow et al 1996)The tide recorder above shows that, the water level has remained continuous about two meters between 1979-1984, and towards the late 1980s due to low tides, there has been drastic shift between 1988 till 1993.Evidence of the high water levels can be seen in 1980, when huge river floods occurred in the telephone exchange river division, accompany with heavy storm surges (Jallow et al, 1996). Conversely the NEA (2000) claimed that the tidal currents mostly influences floods in the river estuary than the coastline, thus are weaker by the coastline Banjul, and higher up to1m/s in the rivers estuary.Figure 3 Current Elevation of Banjul (Jallow et al, 1999)Response strategiesThe Disaster agency mainly undertakes a disaster response and risk diminution system, than a disaster prevention scheme. In 2007, the agency formulated a risk reduction policy, called a hazards Profile of the Gambia and its Vulnerability and Capacity estimate Report, to identify the hazards, and the potential threats it poses to the country to the country (National Disaster Management Agency 2008-2011).In 2008 the Gambia government developed a National Disaster Management Act which stressed, that the all adaptation and precautionary measures undertaken for flood preventions must be effective and capable to serve long-term purposes. Thus in the event of the 2003 flooding in Central River Division (CRD), the practical early prototypes has not been efficient in alerting people forrader floods occurs.In the 2003 event, it was unreliable because it did not reach the entire region. Therefore, a change in its the response strategy of the monitor systems. Post 2003 the government proposes to produce a more resourceful flood risk management plan that consists of geospatial informations to improve the monitoring services to produce positive effective warning systems. There has been a proposal to develop a mapping program to manage the rivers floodplains along central river division (NEA, 2010).Current ly the UNDP in the collaboration of a National disaster management program provides project guidelines on,1. How to review of early warning systems,2. How to analyze management systems, in precautionary measures and3. The provision of regular feedbacks to those responsible stakeholders (NEA, 2010).International responseThe United nations has recommended to the local anesthetic government to develop mawkish channels such as canals and build dams as mechanisms against flood. More over, the government has been has been reluctant, on these developments, especially dams, as they can cause the changes in the line of business of the river and its establishment, has not been financially viable.The UNDP support to the Gambia on floods, encourages a capacity grammatical construction approach, in which grassroots development, enhances the local community with skills on planting mangroves roughly there neighborhood, as preparation plans to deal with the flood waters before flood occurrence (UNDP,2000).Recently, the UN International Strategy for Disaster Reduction (UNISDR) provided skillful support to the Gambias assessment of the national institutional framework for the national program of Action. This was not been supportive because it has not clearly indicate areas prone to river flooding, bring on sea level rise, to provide accurate analysis on research to cope with the risks from both sea level and flooding. Furthermore, the nonexistence of visible flood defenses against flood preventions, and this has been the why vulnerability increases of the countrys liability to floods (NEA, 2010).LONG-TERM plans and RecommendationsConstruction of physical defensesIt is significant to build a low cost seawall or a bulkhead to cope with the effects of sea level and floods along the coastline. The seawall has a 12 slope, a 2-metre beam and a height above water of 1.2 times sea level rise scenario. This would protect the coastline where there land is less than one meter abov e mean sea level, along Banjul area, by the mangrove systems. It is adequate to use dikes made up of about 1.5 to 2 meter to control the water levels (NEA, 2010)Wetland preservation and mitigationThe estuary of the Gambia River contains economically important wetlands and mangrove systems. The mangrove systems on the Kombo St. Mary Island and Kombo Peninsular are regarded as vital breeding movement for various aquatic species. Efforts should be made to protect these areas by declaring them as protected wetlands. This would discourage exploitation of the resources in these wetlands. This can examine the impacts of upstream dams on the Gambia River in terms of reduced sediment supply.Effects of sea level rise on flood risk managementThe constraints that the rising sea level has on flood risk management affects the Gambias land use prep and the water resource management. There is the need to increase the use of floodplains against floods, and also development the rivers basin.Water r esource managementIn producing a better river basin, flood management need to identify the conjunction of the rivers flowing patters. The Gambias integrated water resource management ensures that the water role is being preserved, and dams and wells are protected against contamination of the flood waters. When river flooding occurs, the major problems arises from drainage congestion and these are regarded as the significant effects of raising water levels on flood risk management grime use planningThe Gambia needs to map out the most vulnerable locations of flood risks, to enable accurate impact assessments, between land-use planning and the defense of the infrastructures. Also, the contingency plan should include flood scenarios that are beyond the communicate situation, in order to increase its management capacities.The lands office and physical planning should avoid the allocation of lands that are susceptible of flooding. For instance dried up streams in kombo peninsular, co nsists of new settlements, and has recently flooded during the rainy seasons. People residing at areas prone to flooding should be advice to raise their gate above the mean flood levels.ConclusionIt can be concluded that, the impacts of rising sea levels will continue to increase the risk of flooding across the country, if the preventive systems are not enhanced productively in the future. This is because, the Gambia focus all their attention on the response systems, than prevention systems of floods and the effects of sea level rise, rather than tackling the root causes of the problems, and then finding means of preventing its occurrence. Lack of grant data has been a stumbling block in producing the accurate findings, for effective risk management systems. Although, Gambia has been classified as a net sink country, the gist of greenhouse gases eliminate from the atmosphere is more than those produced (NEA, 2010). Yet it is been severely affected by the global climate change effe cts over the last decade. Its management systems undertake an integrated approach, such as policy formulations and contingency plans, rather than establishing of physical defenses.To sum it up, the most important method to manage the effects of sea level rise on floods is to reconstruct those groynes(trunks of rhun ribbon inserted into the sea) in Banjul to capture those sediments transported during erosion (see Figure 5). The construction dikes, can possible be, one of the most efficient form of flood defences. Also, catchment flood management strategy can be an essential tool in providing a sustainable protection on managing flood risks. The facilitation of a catchment flood management plan will enable the Gambia, to benefit from the understanding flood risks of the river Gambia, in order to tackle its consequences efficiently. In this way, the national disaster management and the rest of the stakeholders will undertake a more technical fashion towards their flood management pla n.In addition to that, there has been poor records to assert flood magnitudes and its frequency and if this was available, there will be allocation, there will be accurate analysis that can provide inappropriate technique to manage future flood risk managements for the Gambia.A corporation that brings together the efforts of the local government, UN agencies, NGOs, civil Society and local communities is the most effective form of a achieving a sustainable flood management strategy would create an inclusive disaster management framework in the country and to improve governments capacities to manage and counter to floods effectively.Received feed back supervisor wants me to provide a picture of a dikes, as I have written in my conclusion that, it cal be the most effective form of flood risk of management. Please run this thru your plagiarism website for me. I am in Uni works on my powerpoint slides