CHAPTER and wetter. Thus one can appreciate that

CHAPTER ONEGLOBAL CHANGES AND SUSTAINABLE DEVELOPMENT1.1. GLOBAL CHANGESFifty years from now, computer simulations of how climates will change because of increased CO2 suggest that the earth will be warmer by one to three celcius but with changing rain patterns. Some areas such as Midwest America will be hotter and drier while parts of Africa will be cooler and wetter. Thus one can appreciate that simple physical factors like sunshine, altitude, and temperature demand a response from the community of plants and animals. Some organisms will adapt and survive. Others will fail to do so and disappear. The earth as a planet has been profoundly altered by life. Its air, oceans, soil and rocks are very different from what they would be on a lifeless planet and life has greatly changed the earth’s surface during the last 3 billion years and still continues to modify it. These scenarios are known as global changes.1.2. GLOBAL WARMING AND GREENHOUSE EFFECTIn rcecent past, global observations have provided clear evidence of climatic changes resulting from anthropogenic activities. According to a report from World Watch Institute (1992), the earth’s surface was warmest in 1990. Six of the seven warmest years on record have occurred since 1980. Observations on temperature at many places of the world over the last century show an average increase of about 0.5K. This rise in global temperature is known as global warming. Global warming has been supported by palaeo-climatic evidence gathered from deep-sea ice-cores from arctic and Antarctic regions.4While the primary cause of an increase in global temperature in the past has been increased concentration of CO2, fossil fuel burning, extensive deforestation, rapid increase in chlorofluorocarbons (CFCs) has further complicated the global environmental problems. The minor gaseous constituents, commonly known as greenhouse gases (GHGs) like carbon dioxide (CO2), CloX, methane (CH4), nitrous oxide (N2O), HOX, ozone (O3), CFCs, etc., though occur in traces but lay a surprisingly dominant role in regulating the entire earth atmosphere’s temperature. They act as the glass pans of a greenhouse, which allow solar radiation to pass through and heat the surface of the earth but do not allow the heat radiated from the earth to pass through the atmosphere back to space thereby trapping heat in the process. This heat trapping and ‘recycling’ within the earth’s surface and earth’s atmosphere is known as greenhouse effect.1.3. CLIMATE CHANGEClimate is inherently variable. It varies with over space and time. Climate change is a natural long-term atmospheric process. It has never been static over the broad spectrum of geological timescale. However, human interference has significantly altered the flows and exchanges within the climatic system. The Intergovernmental Panel on Climate Change (IPCC) suggests that the chief human influence on the climate is the general warming effect of the build up of CO2 and other GHGs. In many parts of the world including much of Europe and North America, warming has been partly masked by other pollutants – the aerosols of sulphates and soot that form a thin haze, which reduces solar heating.Greenhouse gases contribute to major climatic changes in developing countries, where increasing populations will require more and more energy resulting5in greater levels of GHGs emissions. According to IPCC estimates, 68 percent of world’s GHGs emissions are likely to be from developing countries by the year 2025. This suggestion forces one to think that impact of climate change will be more severe in developing countries like India and China in the greater Asia, and Nigeria in sub-Saharan Africa, whose economies are largely dependent on agriculture and which are already under stress due to increasing population pressures and associated demands for fresh water, energy and food.6CHAPTER TWOCLIMATE CHANGE AND WATER SCARCITY IN NIGERIA: CASE STUDY2.1. GEOGRAPHY OF NIGERIA2.1.1. Location and Situation, and SizeNigeria is located between the Latitudes 4°N and 14°N, and Longitudes 3°E and 15°E. It is bordered in the west by Benin Republic, in the north by Niger Republic, in the east by Cameroon Republic, in the northeast by Lake chad, and south by Atlantic Ocean. The size of Nigeria is approximately 923,768 km2.2.1.2. ClimateTwo major seasons dominate: harmattan and rainy seasons. Its climate varies between semi-arid in the north to tropical and humid in the south. The average rainfall ranges from about 500 mm/year in the north to over 2,000 mm/year in the south. Most rainfall occurs in well-defined rainy seasons of four to five months (May to September) in the north and six to seven months (April to October) in the south and is typically concentrated in high intensity storms with high rates of runoff.2.1.3. Relief and DrainageThe country is characterized by land of plains at < 300 m and plateaus 300 m - 900 m above sea level. Major Rivers include Niger, Benue, Sokoto-Rima, Hadejia, Gongola, Kaduna, Moshi, Awun, Ogun, Osun, Osse, Katsina-Ala, Donga, Anambra, Imo and Cross Rivers. The northern terrain is flat.2.1.4. BiodiversityNigeria is situated in the tropical belt parallels and spans six major vegetation zones, from mangrove-saltwater swamp to montane regions to grasslands to desert.2.1.5. Population7Nigeria is the most populous country in Africa with an estimated population of 180 million and average density of about 130 persons per sq. km. Population has been growing at an estimated average of 2.9% per annum.2.2. NIGERIAN SITUATION TOWARDS CLIMATE CHANGE AND WATER SCARCITYIn Nigeria, the government is working assiduously to achieve two of its major goals. The first is the Vision 20:2020 and the second, Millennium Development Goals (MDGs). However, the threats of climate change pose a daunting challenge to the realization of these goals.Climate change is a significant global issue during the later part of 20th century. It has also remained of high importance in the 21st century. This is because its effects on the natural environment, agricultural productivity, water availability, quality of life, and the overall economy of the country are increasing and far-reaching.In recent years, however, evidences abound that have set in motion a quest for understanding any observable anthropogenic interruptions and accelerations to the climatic cycles. The studies have therefore yielded outstanding indications. One of this is that humans have dwelled significantly on the natural environment, an invaluable resource that results from nature's efforts over tens or hundreds of thousands of years but, human efforts have destroyed this resource in only a few years.In Nigeria, for example, The main reason for the land use intensification was and still is the increase in food production required to feed the rapidly growing population. For example, the Nigerian population has increased from 115 million in 1991 to 140 million in 2006 (Federal Republic of Nigeria, 2007). In order to maintain8soil losses within tolerable limits, similar to those which occur in nature, as for example in a forest, a farmer must cause minimum soil disturbance regardless of the situation and the agricultural activity. Therefore, soil and water conservation techniques remain an indispensable tool in sustaining crop production especially on farmlands under severe soil degradation.2.3. WATER SUPPLY OPTIONSSources of water supply in urban areas include piped supplies from overnment establishd water corporation and also from commercialized waters supply business units (Gbadegesin and Olorunfemi, 2011). In rural areas, water is commonly sourced through wells, boreholes fitted with hand pumps, and sometimes, small piped network (Montangero, 2009).2.4. PROBLEMS OF WATER SCARCITYAfter all efforts tailored towards sustainable water supply in Nigeria, about 40 per cent of the population still do not have access to safe drinking water. In rural areas, more than 50 per cent of the of the inhabitants do not have access to potable water (National Millennium Development Goals Report, 2005). Many of them still live directly on the available natural/open water sources in the physical environment, which are mostly not available during dry season. Higher cost is incurred if they have to outsource these open water sources (IDRC, 2002).2.4.1. Urban Water SupplyAccording to Government of Nigeria Water Supply and Sanitation Baseline Study (WSSBS, 2007) 69.3 percent of urban inhabitants have access to water while9ccording to the UNICEF/WHO (2009) Joint Monitoring Programme (JMP), 79 percent (27 million) of the urban population had access, but coverage had dropped to 75 percent (54 million) by 2008. Over the same period 1990–2008, the proportion accessing water through household connections dropped from 32 percent to 11 percent, while the WSSBS reported 12.7 percent as the household connection rate. The lower estimates provided by the WSBSS may be associated with the categorization of the population into rural and urban, as the rural access figure reported by the JMP in 2008 is lower (42 percent) than that reported by the WSSBS for 2007 (49.9 percent). Required capital expenditure (CAPEX) for urban water supply (UWS) is estimated at US$1.1 billion annually.2.4.2. Rural Water SupplyRural water supply (RWS) in Nigeria was estimated by the WSSBS in 2007 at 49.9 percent. This contrasts with the JMP's estimate of 42 percent in 2008, up from 30 percent in 1990. According to the JMP, over 1990–2008, household connections decreased from 4 percent of the rural population to 2 percent indicating a greater emphasis on other options for improved water supply. Nigeria will miss the rural share of the national (MDG Office) target for water supply by a significant margin (22 percentage points).2.5. PROBLEMS RESULTING FROM CLIMATE CHANGE AND WATER SCARCITYAccording to FME (2011), climate change will affect the nature and characteristics of the freshwater resources on which Nigerians depend. For example, global average withdrawals per person is 800 cubic meters per person per year while in Nigeria it is 50 cubic meters per person per year.10The impacts will vary between eco-zones, exacerbating existing problems of floods, droughts and salt water intrusion. Coastal and marine regions in the country face serious threats from the and a large number of coastal population will be displaced. Accordingly, key impacts of climate change on water availability are:2.5.1. TemperatureIncreased temperature results in:1. Higher surface water temperatures that may lead to habitat loss for some temperature sensitive organisms, and increased abundance of undesirable species (e.g. algal blooms and pest species).2. Higher evaporation and transpiration in plants that could cause reduced availability of surface and groundwater and changes in water quality (particularly salinity).3. Warmer coastal waters which are linked to increased frequency and severity of storms and higher rainfall events.4. Impacts on fisheries, including drying up of breeding habitat in wetlands and changes in species composition and abundance.2.5.2. RainfallIncreased incidence of high intensity (extreme) rainfall events due to climate change could lead to flooding and associated impacts such as:1. Erosion, causing loss of aquatic habitats and productive lands2. Siltation, leading to reduced capacity of lakes/reservoirs, rivers filled with silt (entering cycles of flooding followed by dying), delta accretion, and smothering of mangroves3. Contamination of surface and groundwater, including fish habitats114. Drought induced by reduced rainfall can lead to desiccation and death of rivers, lakes and wetlands and, in turn, lesser available water.2.5.3. Extreme Weather Events1. Greater frequency and severity of coastal storm/sea surge could impact mangroves, which constitute critical breeding habitat for many fish species.2. Drought could reduce or eliminate dry-season habitat critical to sustaining fish populations through the dry season to the next wet season.2.5.4. Sea Level RiseSea-level rise may lead to:1. Salinization, through salt water intrusion, is a major problem.2. Coastal areas are more prone to flooding. It is estimated that 70 million people will be at risk from coastal flooding by 2080 and large cities such as Lagos could be in a verge of being submerged3. An increase in the area of saline and freshwater flooding (wetlands), resulting in an increase in fish habitat, but also changes in species diversity and abundance.2.5.5. Cross-Sectoral EffectsPoor management of climate change impacts in watersheds and in coastal areas will affect other sectors. For example, flooding has direct impacts on communities and infrastructure, and leads to impacts in such sectors as agriculture, water supply, power generation, transportation, and biodiversity.2.6. ADAPTATION/MITIGATION STRATEGIES FOR WATER SCARCITY/CLIMATE CHANGEIn Nigeria, and Africa generally, the impacts of changes in climate on water resources are minor compared to the problems being faced already with the present12climate variability. Coping for present day climate variability' already takes us a long way down the road towards adapting for climate change. The essence of adapting in the water sector is to be able to live in equilibrium with projected water scarcities. Scarcity is influenced by factors at global level (climate change), regional level (land-use change), river basin level (water resource management) and household level (access to water). Adaptation strategies in the water scarcity and climate change should, therefore, include 3 main areas:1. Water exploitation methods2. Water storage methods +rain harvesting3. Water management and planning2.7. CONCLUSIONA major underutilized resource in adaptation resides in the knowledge and initiative of the local peoples themselves. If multilateral initiatives are to produce vital results, they must be adjusted and appropriate to the peoples' cultures, which have embodied adaptations to the rigors of climate variability and change. There is a near absence of appropriate indigenous research, design, and development (RD&D) capabilities. This implies that the African countries in have to depend on imported (high-cost) technology and its supplier for troubleshooting and upgrading needs.One lesson of the past has been that development efforts have relied too much on prescriptions applied without sufficient understanding and sensitivity to the local communities.