Presentation on theme: "Challenges in coping with water problems in the 21st century"— Presentation transcript:
1 Challenges in coping with water problems in the 21st century A. W. JayawardenaInternational Centre for Water Hazard and Risk Management (ICHARM) under the auspices of UNESCO,Public Works Research Institute1-6, Minamihara, Tsukuba, Ibaragi,Japan
2 Contents Introduction Current status Challenges for the future Population growthWater availabilityWater stress and water scarcityChallenges for the futureDrinking water securityFood securityEnvironmental securityDisaster reductionClimate changeConcluding remarks
3 IntroductionOne of the main water problems around the world today is the lack of potable water. After oxygen, water is the most vital ingredient for sustaining life. Food, which requires water for growing comes next.Over one billion (1.1 billion) people in the world do not have access to safe drinking water and about twice (2.4 billion) as many do not have access to proper sanitation.The consequences of not having access to safe potable water are serious particularly in developing countries which suffer from various types of water-borne diseases some of which result in premature death.The main challenge for future is how to guarantee water and food security to all inhabitants of the world.
4 Water withdrawals by sector (Source: IWMI, 2006)
5 Current status: Population growth Although the total water resources remain reasonably constant, the per capita share is continuing to go down as a result of increasing population.It is also predicted that the population will continue to increase until about The positive trends can be attributed to a number of factors such as improved medical facilities, low infant mortality rates, increased life expectancy and increased food production.The population which in 1750 was 791 million has exploded to 6.93 billion in July 2011 (en.wikipedia.org/wiki/World_population), with the highest rate of growth of 2.2% per year recorded in 1963.China and India alone have (19.33%) and 1.21 billion (17.46%)respectively.Despite the past trends, it is also well known that continued increase is not sustainable as the competition for resources will begin to dominate the growth rate sooner or later.An important resource that could dominate the growth rate is water.
7 Current status: Water availability Fresh water – only about 2.5%Includes the water content of ice caps and glaciers, inland lakes, soil water, ground water, atmospheric water and river and stream storageThe extractable part is only of the order of about 0.5%.Sea water – remaining 97.5% (not suitable for human use except by way of desalination)Although renewable and abundant in nature, fresh water has spatial and temporal variability. It is this temporal and spatial variability and the changing life styles that lead to water stress and water scarcity.
8 Current status: Water availability…… A country or region may be considered as “water-rich” or “water-poor” by the per capita amount of water available.Water-rich countries includeGreenlandIcelandGabonPapua New GuineaCanadaNew ZealandWater-poor countries includeBotswanaChadNamibiaUnited Arab Emirates
10 Current status: Water stress and water scarcity Water stress occurs when the available supply is unable to meet the demand during a certain period or in a certain area.Water stress can occur as a result of the physical lack of water, poor quality or being economically unaffordable.Quantitatively, a region is considered as under water stress when the annual per capita water availability is less than 1700 m3, and under water scarcity when it is less than 1000 m3 (Falkenmark and Lindh, 1976).Another indicator that has been used to quantify water stress is the percentage of the land area under severe water stress. In terms of the latter, Israel and Trinidad and Tobago each have 100% of the land under water stress. (http://www.nationmaster.com/graph/env_wat_ser_str-environment-water-severe-stress).Water stress occurs in many countries, some to a lesser degree than others. The sub-Saharan African region is perhaps the most vulnerable.
11 Water stress in some selected countries RankingCountryPercentage of land area under water stress1Israel1004Nepal98.123Pakistan76.324India60.236China44.740Sri Lanka39.550Bangladesh22.162Japan9.593Iceland
12 Current status: Water stress and water scarcity…. Water stress and water scarcity can lead to economic, social, environmental and health problems. Lack of water in sufficient quantities affects agricultural and industrial production, whereas lack of water in acceptable quality affects the environment and health of the community. Poor quality water is fertile ground for growth and spreading of pathogenic organisms.Water stress can also be caused by political conflicts in landlocked countries. When the upstream countries control the resources of trans-boundary rivers inequitably, the downstream countries suffer. Water has been the root cause of many international conflicts which in some cases have led to wars.Although water is freely available in nature, it has an economic cost when it is delivered to the consumer for domestic, agriculture or industrial use. Therefore, water stress and even scarcity can occur in a place with abundant natural water if the community is unable to afford it. Such instances have led to many political and social issues when attempts to privatize the water industry are made.
13 Challenges for the future: Drinking water security The health of a nation depends upon the level of cleanliness of the domestic water supply. It is a problem that is often ignored or sidelined by developed countries as it is only a problem of the poor and the developing countries.Unlike a major flood, an earthquake or tsunami which affect a small region with high population density, the effect of the lack of drinking water is spread over vast areas with relatively low population densities.From the media point of view, such widespread and prolonged suffering receives much less attention compared with that received for high impact type of disasters such as earthquakes, tsunami and major floods.
14 Challenges for the future: Drinking water security….. Arid and desert areas suffer from physical lack of water and such areas also experience pollution problems.Traditional techniques such as rainwater harvesting, and groundwater exploitation would be better appropriate technologies than conventional water supply technology.It is also important to introduce low cost water filters which can be used in individual households. It is estimated that $1 invested in improving access to safe water can increase the GDP by $3-14.
15 Challenges for the future: Food security The global average food intake has increased from 2250 kcal in 1961 to 2800 kcal in 2000, although, in South Asia and sub-Saharan Africa, it still remains at 2450 kcal and 2230 kcal respectively (IWMI, 2006).This increase may be attributed to a number of factors. Land and water productivity has increased with average grain production from 1.4 Tons/ha to 2.7 Ton/ha during the last 4 decades (IWMI, 2006).Global trade in food products also has increased thereby increasing the flow of virtual water.On the negative side are the facts that the population is still increasing, and that the increases are in areas where productivity is low and with inadequate human and economic capacities to upgrade their production.
16 Challenges for the future: Food security….. It is a fact that grains have been the basic form of food for all humans.With increasing affluence, meat, milk and fish consumption have increased substantially thereby exerting an additional water cost to food products.On a global scale, agriculture uses about 70% of the world’s water resources, followed by industry which uses about 22%. (Domestic water accounts for about 8%)In recent years, many countries have embarked on the production and use of biofuels in place of fossil fuels. This practice also has added a further burden of our water resources because of the additional quantities of water needed for growing the bio species from which the biofuels are extracted.
18 Challenges for the future: Food security….. The challenge in this context is how to produce our food (and energy sources) at the least water cost.Large scale crop production necessarily depends on irrigation to ensure guaranteed successful harvest.Rainfed cultivation on the other hand is weather and climate dependent and therefore does not guarantee a successful harvest every year.The water efficiency in irrigated cultivation is always low. Flooded irrigation results in evaporation from the free water surface as well as from the bare soil.In order to increase the water productivity, it is necessary to reduce crop evapo-transpiration. Better and more efficient techniques such as drip irrigation, low pressure sprinklers are currently being used to increase the water productivity.
19 Challenges for the future: Food security….. Food trade is another area that requires attention.It is not meaningful to attempt to grow food in water-poor regions at high costs and consequent environmental degradation.With global trade expanding, it is quite logical to grow more food in water-rich regions and make them available as food products to those in water-poor regions.However, in the present context, many countries aspire to be self sufficient in food for strategic reasons. Such aspirations will not be needed if fair and reasonable trade agreements and treaties to share trans-boundary water resources are in place.Above all, concern for the well being of other human beings should be the guiding principle for sharing the water resources on earth.
20 Challenges for the future: Environmental security Environmental pollution is a by-product of economic development and goes unabated in many waterbodies as a result of indiscriminate dumping of domestic, agricultural and industrial wastes.When the release of wastes into such waterbodies exceed their capacities to self purify, they will become ‘dead’ when no living organism can survive.Slow accumulation of pollutants over the years in many rivers (e.g. in China and India) has made them aesthetically unpleasant and biologically and chemically toxic.Restoration of such rivers to environmentally acceptable levels is costly and a fair and reasonable approach to recover costs is to follow the polluter pay principle.
21 Challenges for the future: Environmental security…. Many countries have enacted legislation to address this issue but the enforcement becomes difficult as the costs are passed back to the consumers by the polluters as increased costs of their commercial products.How the benefits arising from development activities should be balanced against environmental costs is a major issue that needs to be considered holistically in the context of the total water environment rather than as isolated systems.
22 Challenges for the future: Environmental security…. Incidents of pollution caused by accidents such as the one that occurred in Songhwa River in Northeast China are also on the increase as more and more toxic industrial ingredients are conveyed too frequently and over long distances.Introduction of advanced methods of waste water treatment such as membrane technology, recycling, reclamation of waste water etc. help alleviate the pollution problem to some extent.In the long term, an integrated approach of water management in which all aspects of the water sector are considered and optimized within the framework of a single ecosystem appears to be the way forward.
23 Challenges for the future: Disaster reduction Another challenge lies in the area of water-related disasters. Water, despite being essential for all forms of life can also at times be destructive.Floods, landslides, and debris flow are all triggered by excess water. Many regions in the world are vulnerable to water related disasters and the damage as well as the resulting casualties are on the increase.According to a report by ICHARM (Adikari and Yoshitani, 2009) based on data compiled by EMDAT, there have been 3050 incidents of flood disasters during the period causing economic damage to the extent of US$342 billion.It is also important to note that not only the numbers of disasters are increasing but also the number of people affected too because of migration of people into areas with better economic prospects.
25 Challenges for the future: Disaster reduction…. A hazard becomes a disaster when the region and the community are vulnerable and lack the coping capacity.Therefore any approach for mitigating the consequence of a disaster needs to focus on reducing the vulnerability and enhancing the coping capacity.Although there are many international and regional initiatives aimed at disaster reduction, their implementation is slow and lacks high priority due to political, cultural and economic issues particularly in developing countries.It should also be recognized that capital intensive engineered approaches of disaster reduction practiced in developed countries cannot be applied in developing countries.
26 Challenges for the future: Disaster reduction…. It is only when the community attains a certain degree of affluence that people will begin to think about disasters and invest in disaster mitigation measures. For those living at or below the poverty line, day to day survival by itself is a disaster, and it is very difficult to get them involved proactively on implementing mitigative measures.Although investment in disaster mitigation is considered as a development issue in developed countries, there are other areas of higher priorities where investments need to be channeled in developing countries.More can be achieved by promoting non-engineered approaches of coping with disasters as well as assisting in upgrading the living standards of those in less developed countries.
27 Challenges for the future: Climate change Climate change is currently a hot topic. The Intergovernmental Panel on Climate Change (IPCC) has concluded that climate change is anthropogenic and that greenhouse gases (CO2, CH4 and N2O) are the cause of the current global warming.According to the IPCC report, the concentrations of CO2, CH4 and N2O have increased from 280 to 379 ppm, 715 to 1774 ppb and 270 to 319 ppb respectively between pre-circa 1750 and 2005.Global average temperature has increased by 0.74°C during Sea level has risen by 0.17 m in the same period (57% due to thermal expansion; 28% due to melting of glaciers/ice caps; 15% due to melting of Greenland/Antarctica ice sheets).
28 Challenges for the future: Climate change…. Skeptics are of the view that the IPCC report is politicized and accepted by Governments on a consensus basis rather than on scientific logic, that a Global Warming Petition refuting the conclusions of the IPCC Report has been signed by 31,072 US scientists including 9,021 Ph.D’s, that the IPCC Report peer review process has not been independent and thorough and that the increase in CO2 does not necessarily increase the temperature at the same rate.There have been noticeable warming during but the CO2 increase has not been significant.
29 Challenges for the future: Climate change… Challenges for the future: Climate change….(Lessons learned from COP 15)The first lesson is that climate change is not just a matter of science but also a matter of geopolitics. Without improved geopolitics, there can be no real fight against climate change. The expectation at COP series that scientific-research results would trump geopolitics was belied.The second lesson from the COP series is that to get an international deal, there first must be a deal between the U.S. and China. These two countries are very dissimilar, yet they have a similar carbon profile: Each contributes between 22 to 24 percent of all human-induced greenhouse gases in the world.A third lesson from COP 15, being reinforced by the present circumstances, is to have a more-realistic agenda. Too much focus has been put on carbon cuts for nearly two decades, almost to the exclusion of other elements. It is now time to disaggregate the climate-change agenda into smaller, more manageable parts. After all, a lot can be done without a binding agreement on carbon cuts through national targets.
30 Climate change: Some facts Temperature which varies with position and time (about -50 to +50°C) is used as an indicator of warming. In this context, the definition of global temperature is not quite clear. Also, the variation is greater in the Polar Regions while it is reasonably constant in the equatorial regions.Projections made into the future climate have many uncertainties. These include model uncertainties, data length and their representativeness, calibration and validation issues, and the logic of projecting into 100 years or more into the future with a relatively short window of observations.
31 Climate change: Some facts…. Earth has gone through cycles of warming and cooling in the past. Changes have persisted over decades and sometimes over centuries.Although instrumental measurement of temperature started in 1850, various proxy methods (such as tree rings, ice cores, corals etc.) have been used to understand Paleo-climatology.For example, the Holocene warm period (circa BP), the Roman warm period (circa AD, the medieval warm period (circa AD) and the little ice age (circa AD).It has been shown that there is a 1500-year cycle of global warming.
32 As recorded in ice cores from Vostok, Antarctica, the temperature near the South Pole has varied by more than 20 degrees Fahrenheit during the last 350,000 years. There have been peaks of warmth approximately every 100,000 years. The temperature and the carbon dioxide concentrations at the South Pole parallel each other. The rise and fall of temperatures gives rise to the ice age/interglacial cycle.
33 Climate change: Some facts…. Severe storms are another indicator of climate change. They are caused by the temperature differential between the polar and equatorial regions.During warm periods, the temperature of the Polar Regions would be higher whereas in the equatorial regions there would not be much change, leading to fewer storms.It has been reported that there were less than half as many major Caribbean hurricanes per decade during , than that have been recorded in the past 50 years
34 Climate change: Some facts…. Such climate variabilities have taken place without human intervention.The main factor that would have caused periodic warming and cooling is the fluctuation of energy from the sun and the oceans (El Nino and La Nina effects).Solar variability and orbital mechanics play a significant role in controlling earth’s climate.Some cities have shown consistent temperature rises over the past few decades (For example, Tokyo, Johannesburg, Beijing etc). Some other cities have shown consistent cooling over the past few years (For example, Jerusalem, Quebec, Antananarivu etc.). Many cities in the world show cyclic temporal patterns of temperature variation (New Orleans. Cairo, Paris, New Delhi etc.). The winter in 2007/2008 in China has been the coldest in recorded history.
35 Source: Goddard Institute for Space Studies http://data. giss. nasa
39 Climate change: Some facts…. If CO2 is the main cause of global warming, the CO2 would first warm the upper atmosphere, and then the earth’s surface. Measurements of atmospheric temperatures by remote sensing show no sign of warming of the upper atmosphere during the last century.
40 Source: Kenneth Rundt (2008): Global Warming – Man made or Natural?
41 Climate change: Some facts…. Some scientists believe that the warming has peaked and that the earth is more resilient than predicted.UN has warned that extreme winter has killed more than 1 million livestock animals in Mongolia in 2009/10 winter, and is likely to harm its food supply and worsen poverty. During zud (extreme winter), the average temperature has reached -55°C when it should have been about -35°C.
42 Climate change: Some facts…. The IPCC has admitted some errors in their report (For example, the melting of the Himalayan glaciers by 2035). – Glacier-gateJust before COP15 there was the "climate-gate," - the publication of damaging and other documents from the Climate Research Unit at University of East Anglia exposing highly politicized scientific research in the form of manipulated or suppressed data on human-driven climate change.NASA satellites show that the Earth has become 6% greener as the world has warmed over the past 20 years.The temperature measurements made are normally in cities where the ‘heat island’ effect can be significant. It is not clear how this effect is taken into consideration in the IPCC predictions.Instrument calibration is another issue. Is it fair to compare measurements made in the early days with the measurements made today? There have been significant changes in the way temperatures are measured and their levels of accuracies.
43 Climate change: Some facts…. In a dynamic world, not only the climate, but many other things are also changing. The most important change is the change in population. The publicity given to population change is far less than that given to climate change thereby distorting the real issue.There are arguments and counter arguments which confuse the public. What is really needed is factual information to enlighten the public rather than opinions or conclusions based upon uncertain information.Rather than addressing the issue on a global scale, more should be done to clarify reality that exists locally. It is better to measure any climate change locally and be convinced than being told that there is climate change. The issue should not be like the chicken little’s story - “sky is falling down”.Actions should be based on common sense regardless of whether the earth warms or cools. Conservation should be encouraged and practiced at all levels.
44 Climate change: Some facts…. More people die from cold than from heat and no place on earth is too hot for humans. Throughout human life, the earth has been a better place to live under warm climate than cold climate.Scientific information, data and the results of analysis as well as the uncertainties of predictions should be made public. Merely saying that the temperature in the year 2100 will be 2°C higher does not make scientific sense unless the method, data used and the assumptions that have been made to arrive at the result are also explained.Some scientists believe that the contribution by CO2 to influence temperature is far less compared to water vapour, solar variability (radiation and magnetic flux) and orbital mechanics.
45 Climate change: Some facts…. It is a fact that there is a pool of government sponsored research money waiting to be grabbed for ‘climate related research’. The findings of such research may be biased as the researchers are motivated by their self interests to secure continued funding rather than finding the truth. The ‘inconvenient truth’ is that the issue is not universally accepted.There is also the counter belief that the skeptics are on the payroll of oil companies and others who have vested interests.Is climate change the cause or the effect? Should we address the cause or the effect? It is not necessary to use climate change as a justification to reduce over-consumption and wastage. It should be natural.Should we follow a ‘global approach’ or a ‘local approach’?
46 Concluding remarksResponding to different challenges sometimes need addressing conflicting interests.If any of the above challenges are taken in isolation, other challenges may have to be overlooked or ignored.In such situations, a holistic approach giving consideration to the long term sustainability of the entire water sector would be the way forward.An approach in which a balance is sought between development and conservation, and where modern technology and traditional practices go hand in hand would be ideal but the implementation of such an approach requires the will and commitment of all stake holders to share this precious resource of the planet earth in an equitable manner.Failure to do so will result in a situation whereby the water-rich countries can starve the water-poor countries when conflicts reach critical stages.In the not so distant future, water will take the place of oil as a political and economic tool that can be used to manipulate communities and governments.
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