Survive Global Water Shortages

US Water Revolution

Due to intense governmental pressure and highly illegal Federal dealings, the water crisis that faces California and most of the Western United States are NOT a result of natural causes. They are the direct result of a chemical warfare that is going on NOW to decrease the population of the United States by making water more and more rare in the West. The weather patterns do NOT match up with established scientific data Global warming does not explain this decrease in water, and traces of hydrophobic chemical have been found all over the western United States. The government has been doing its work quietly, but efficiently! Will you take that lying down? Will you let the government kill you and your family? Learn how to help your family during this time; this ebook teaches you the skills you need to know to extract water from any sources and use it to grow food for your family.

US Water Revolution Overview

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Agricultural Drought Risk Management Understanding the Hazard and Societal Vulnerability

Many people consider drought to be largely a natural or physical event. Although all types of drought originate from a deficiency of precipitation, it has both a natural and social component, tte risk associated with drought for any region is a product of both the region's exposure to the event (i.e., probability of occurrence at various severity levels) and the vulnerability of society to the event, tte natural event (i.e., meteorological drought or the drought hazard) is a result of the occurrence of persistent large-scale disruptions in the global circulation pattern of the atmosphere. Exposure to drought varies spatially and there is little, if anything, that we can do to alter drought occurrence. Vulnerability, on the other hand, is determined by social factors such as population changes, population shifts (regional and rural to urban), demographic characteristics, land use, environmental degradation, environmental awareness, water use trends, technology, policy, and social...

Drought Understanding Vulnerability

Recent droughts in developing and developed countries and the concomitant impacts and personal hardships that resulted have underscored the vulnerability of all societies to this natural hazard, ttis appears to be a clear sign of increasing societal vulnerability resulting from unsustainable resource use and growing pressures on natural resources. As noted previously, many factors are contributing to this trend. Adding to the concern regarding increasing societal vulnerability is distress over how the threat of global warming may increase the frequency, severity, and duration of extreme climate events in the future. As pressure on finite water supplies and other limited natural resources continues to build, more frequent and severe droughts are cause for concern in both water-short and water-surplus regions where conflict between water users has increased dramatically. Conflict has also increased within and between countries because transboundary water issues are exacerbated during...

Decision Support Toolsfor Drought Risk Management

Tte mission of the National Drought Mitigation Center (NDMC) at the University of Nebraska-Lincoln is to lessen societal vulnerability to drought through the application of appropriate risk management techniques, including development of preparedness plans and improved drought monitoring and early warning systems and the adoption of appropriate drought mitigation measures, tte NDMC was formed in 1995, and it has been working with local, state, and national government in the United States foreign governments international organizations and others to build awareness of drought and to implement strategies to lessen risk, tte NDMC's mission is much broader than just the agricultural sector. Agriculture is certainly one of the most drought-affected sectors, and it is one in which substantial reductions in vulnerability can be achieved through changes in management. However, in many cases, this requires access to better and more timely information. For this reason, the NDMC is focusing...

Vegetation Drought Response Index VegDRI

Drought monitoring is challenging because of the considerable variability in the duration, intensity, and spatial extent among specific drought events. Climate and weather data traditionally have been used to monitor drought, but the information has lacked the spatial detail required for local livestock and forage producers to use for drought planning. In response, the NDMC is developing two tools, the Vegetation Drought Response Index (VegDRI) and the Vegetation Outlook (VegOut), which utilize a combination of climate, satellite, oceanic, and biophysical (land cover and soils information) data to map and monitor the impact of drought on general vegetation conditions. Both tools produce maps at 1-km2 spatial resolution that are updated every two weeks to reflect the changing vegetation conditions, tte goal is to create tools that provide timely and more spatially precise drought-related information that can be used by livestock and forage producers in their decision-making process,...

Ranching Drought Plan A Drought Planning Tool for Livestock and Forage Producers

According to the National Drought Policy Commission report, Preparing for Drought in the Twenty-First Century (2000), many agricultural producers do not have access to information to develop and implement a drought plan, and even fewer producers are receiving technical assistance to help them develop and implement such plans. In order to address this problem, the NDMC is developing a model drought planning process and web-based educational delivery system for forage and rangeland producers. tte NDMC is working collaboratively with the University of Nebraska-Lincoln's (UNL) Cooperative Extension Service and Department of Computer Science and Engineering, livestock and forage production consultants, and individual ranchers to identify essential planning components and develop a generic drought planning process that can serve as a template for producers to follow. Tasks being completed for this project include Conducting a review of existing literature on livestock production and drought...

Freshwater Resources10

The availability of water for human and ecosystem use depends on two main factors (1) the climate-driven global water cycle and (2) society's ability to manage, store, and conserve water resources. Each of these factors is complex, as is their interaction. Water cycling which includes evaporation and transpiration, precipitation, and both surface runoff and groundwater movement determines how freshwater flows and how it interacts with other processes. Precipitation amounts, intensity, geographic distribu

Research Needs for Advancing Science on Freshwater Resources in the Context of Climate Change

Changes in freshwater systems are expected to create significant challenges for flood management, drought preparedness, water supplies, and many other water resource issues. Responding to these challenges will require better data and improved model projections as well as a better understanding of both the impacts of climate change and the role of water governance on future water resources. Significant gaps remain in the knowledge base that informs both projections of climate impacts on water resources and governance strategies that can build adaptive capacity of water systems to climate effects. Key research needs, which are explored in more detail in Chapter 8, include the following Improve projections of changes in precipitation and other water resources at regional and seasonal time scales. Develop vulnerability assessments of the diverse range of water users and integrative management approaches to respond effectively to changes in water resources.

Climate Change and Water Resources Challenge of Our Civilisation

Abstract The geological view to the issue of impact climate change on water resources on the Earth is the main objective of the paper. The geological excursion into the past of the Earth clearly shows that the climate cannot be stabilized. The volume of water existing on the Earth is stable and has never changed. About 96 of countries have sufficient resources of water. The major reason for water scarcity on the Earth is not unfavorable distribution of natural resources but poverty and lack of education. Keywords Climate change Geological time scale Water scarcity

Hydrology and water resources

This section focuses on the relationship of runoff, lake levels, groundwater, floods and droughts, and water quality, with observed climate variability, climate trends, and land-use and land-cover changes reported since the TAR. The time period under consideration is primarily 1975 to 2005, with many studies extending to earlier decades. Observed changes in precipitation and aspects of surface hydrology are described in more detail by Trenberth et al. (2007), Section 3.3. At present, no globally consistent trend in lake levels has been found. While some lake levels have risen in Mongolia and China (Xinjiang) in response to increased snow and ice melt, other lake levels in China (Qinghai), Australia, Africa (Zimbabwe, Zambia and Malawi), North America (North Dakota) and Europe (central Italy) have declined due to the combined effects of drought, warming and human activities. Within permafrost areas in the Arctic, recent warming has resulted in the temporary formation of lakes due to...

Water Resources And Temperature Rise

Researchers around the globe have found that climate change is likely to impact water resources depletion and pollution significantly. There have been observed changes in surface temperature, rainfall, evaporation, and extreme events since the beginning of the 20th century. The atmospheric concentration of CO2 has increased from about 280 parts per million by volume (ppmv) to about 369 ppmv, and the global temperature of the Earth has increased by about 0.6 degrees C. The present CO2 concentration has not been exceeded during the past 420,000 years and likely not during the past 20 million years. The current rate of atmospheric CO2 level increase is unprecedented during at least the past 20,000 years. About 75 percent of the anthropogenic emissions of CO2 to the atmosphere during the past 20 years is attributed to fossil fuel burning. The rest is predominantly due to land-use change, especially deforestation. Increased surface temperatures of the Earth are causing glaciers to melt...

Freshwater Supply Issues

Impacts of climate change on water resources will have a wide range of consequences for coastal ecosystems. The health of the Earth's ecosystems will be affected by changes in the quality and quantity of freshwater runoff into coastal wetlands, higher water temperatures, extreme runoff rates or altered timing, and the ability of watersheds to assimilate pollutants and wastes. Global climatic changes could pose a serious demand on the water supply. In most regions of the world where there are observed and projected declines in per capita average of annual freshwater availability, coupled with attendant population growth, the possibility of increased demand for water will likely lead to increased withdrawal of water, which will invariably reduce the recharging time of the water tables. These changes may influence a wide range of water-system components, including reservoir operations, water quality, hydroelectric generation, and navigation. In some regions, where large volumes of water...

River runoff variability during the 19821994 drought period

A recent study (Gerassimov et al. 2001, 2004a, 2004b) concerned water resources in Bulgaria during the 1982-1994 drought period. An investigation was made of precipitation (P, mm) and river discharge (runoff depth, h, mm) for two periods one with a duration of 13 years (the drought period) and the other with a duration of 106 years (1890-1995). In these studies the river discharge is calculated and used in total depth of runoff. The authors concluded that the drought period had a strong negative impact on river runoff in the country. The statistical descriptors of data such as the (arithmetic) mean (X) and standard deviation (o-) of discharge and precipitation, with comparison to the long period of 106 years, are presented in Table 2 according to Gerassimov et al. (2004a). From Table 2 it is possible to conclude that during the drought period the average values and standard deviations are considerably lower compared to those of the long series. The reductions of these values are most...

Drought Impacts on Tree Growth and Mortality of Southern Appalachian Forests

In recent years, however, Coweeta has experienced several droughts that have caused significant tree growth reduction and increased mortality rates (Swift et al. 1990 Clinton et al. 1993 Vose and Swank 1994 McNulty and Swank 1995). In this chapter, we describe the general climate and features of Coweeta as well as the impact of droughts on tree growth and mortality. The timescale of this climate variability is annual, with the potential for preexisting soil moisture conditions either providing a buffer or further exacerbating the drought conditions.

Heatwaves and droughts

By studying weather and climate data gathered from all over the world, and transmitted from orbiting satellites, scientists can compare it with past records to work out how much the world has warmed up. But for many people, the evidence of climate change is much more obvious. They are suffering heatwaves that can raise temperatures to lethal levels, and living with droughts that make drinking water scarce, kill their crops and farm animals, and turn fertile land to desert. Some of the droughts may be caused by natural cycles, and deserts can be partly created by poor farming methods such as overgrazing by livestock. But there is little doubt that periods of seriously hot or dry weather are getting more frequent. Reduced rainfall is making some rivers dry up. In 2005 they included the greatest river of all, the Amazon, which suffered its worst drought in 40 years. Many of its tributaries shrank to a fraction of their normal width, exposing broad areas of dried, cracked mud littered...

Improving Analytical Tools for Monitoring Drought and Desertification

A dearth of effective, practical tools for assessing and monitoring drought has constrained the fight against desertification. Oasis is fostering the use of quantitative and analytical methods for direct measurements of ecological processes such as evapo- transpiration from inexpensive, frequently-sampled satellite data (Rosema 1993). These remote sensing analyses are combined with on-the-ground participatory assessments of community perceptions and valuations of drought and degradation. Combined with an understanding of ocean-atmosphere interactions, these tools will significantly strengthen the capacities of communities, nations and regions to develop drought and desertification predicting and coping strategies and tools.

Farmer Perceptions of Drought

A recent Oasis study in Burkina Faso (Slegers et al. 2004) found that farmers' perceptions of drought differ significantly from those of research institutions. Farmers are more focused on the agricultural and local-context effects of drought (crop stress, local variations in stress) whereas researchers tend to concentrate on the regional and meteorological aspects (regional rainfall and temperature patterns, soil erosion and impoverishment). To be more relevant, researchers need to translate their macro-level observations into micro-level recommendations that can help farmers reduce their vulnerability under the particular conditions of their own plots.

Livestock and Drought

ILRI and ASARECA, with USAID support, conducted a survey of 663 households investigating coping mechanisms of pure-pastoralists and agro-pastoralists, during the 1995-1997 drought and 1997-1998 El Ni o rains (floods) in Ethiopia, Kenya, Tanzania and Uganda (Ndikumana et al. 2002). The DMP conducted a similar enquiry in Kenya (Anonymous 2004). The majority of respondents among four tribes in dry areas of Kenya were aware of traditional signs that they felt had predictive power for weather, vegetation and soil conditions. Systems analysis revealed a number of opportunities to help herders improve their preparation and coping strategies. If droughts could be foreseen longer in advance, herdsmen could reduce herd size in an orderly way, avoiding panic sales. Cooperative action among herders could avoid them being exploited by middlemen e.g. in panic sales of livestock that depress markets and strip the herders of their capital assets. Coordinated downsizing and rebuilding of herds could...

Drought Monitoring and Planning for Mitigation

Drought is a climatic hazard that occurs in almost every region of the world. It causes physical suffering, economic losses, and degradation of the environment. A drought is a creeping phenomenon, and it is very difficult to determine when a dry spell becomes a drought or when a severe drought becomes an exceptional drought. It is slower and less dramatic than other natural disasters, but its effects are long lasting and widespread. The cost and misery suffered from a drought are more than typhoons, earthquakes, and all other sudden climatic hazards. A drought results in less water in the soil, streams, and reservoirs, less water for livestock and wildlife, and poor crops and pastures. A chain of indirect effects follows which may include depressed farm income, closure of farm-supporting industries, and reduced hydroelectric power. A drought often induces malnutrition, disease, famine, population migration, and a chain of consequences for farm families (Stehlik, Gray, and Lawrence,...

Increasing drought Risk with Global Warming in Europe

Increased drought risk associated with global warming and impacts on water resources are among the main concerns among agrometeorologists in Europe (Fig. 8.1). Several recent studies highlight the challenges that result from changes in water availability and water quality (EEA 2004, IPCC 2001, IPCC 2007, Schr ter et al. 2005, EEA 2005a). ed water is used for agriculture, in the southwestern countries (Portugal, Spain, France, Italy, Greece) about 46 and in the central and northern countries (Austria, Belgium, Denmark, Germany, Ireland, Luxembourg, Netherlands, UK, and Scandinavia), to the contrary, agricultural use of the extracted water is limited to less than 5 (Eisenreich, 2005). By far the largest part of the water used in agriculture is used for irrigation, ttis percentage approaches 100 in the southern European countries, which at the same time have the largest share of irrigated land in Europe. While the expansion of the irrigated areas, mainly in the Mediterranean, has raised...

Spatial Characteristics of Drought

To characterize the spatial distribution of drought throughout the North Central Region, the HPR was associated with the geographic center of each county. ArcView GIS software (ESRI 1999) was used to interpolate a surface of HPR based on the spatial association between points using the inverse distance weighting (IDW) algorithm and a spatial moving average by associating 12 nearest neighbors to interpolate values of HPR between the 1055 points. Surface grid maps of HPR were developed based on monthly values of HPR at each location, and maps of cumulative HPR from May to July were produced. Two maps based on HPR were developed using this method one shows the 20-year mean (figure 4.7b) and one shows only 1988 values (figure 4.7a). The higher HPR values (i.e., HPR > 15), based on the 20-year mean, occurred primarily in the western third of the region. However, in 1988, high values of HPR (HPR > 30) occurred in central Michigan, Illinois, and Iowa, and in parts of Minnesota and North...

Drought Monitoring In Australia

There may be few countries in the world where drought occurrence is more frequent than in Australia. Every state has developed its own procedures to identify and monitor the drought situation. Drought eased, but still serious Drought continues, rain urgently needed Potential yields severely cut by drought NSW Agriculture has been monitoring the monthly status of drought in New South Wales. Based on this assessment, the government has provided various forms of assistance to drought-affected people. To complete this procedure, Rural Land Protection Boards (RLPBs) supply the relevant data. The RLPBs supply the information in a standard format. The information given is on meteorological conditions agronomic conditions stock numbers (change from normal) livestock condition agistment of stock (change from normal) hand feeding (change from normal) water supply environmental conditions other drought-related factors and the overall recommendation of the board....

Breeding Approaches for Heat and Drought Adaptation

Conventional breeding approaches have had considerable impact in marginal environments as well as favourable ones. For example, economic analysis shows that in the late 1990s, around 25 of global wheat production increase came from improved production in marginal environments (Lantican et al., 2003). Much of this impact was achieved by combining genes of major effect associated with agronomic type, phenology and disease resistance into good yielding backgrounds. However, impacts have also been achieved more recently through targeting specific heat- and drought-adaptive traits in cereals. These have typically occurred for integrative traits, such as transpiration efficiency and canopy temperature (CT), which are composite measures of numerous physiological and morphological processes.

Impacts of Climate Change on Groundwater Resources Review of a Case Study in Azerbaijan

Abstract Groundwater and surface water are the sources of water supply in Azerbaijan. The hydroeconomic balance of Azerbaijan is characterized by annual and seasonal deficits arising from the implementation of hydroeconomic measures for increasing the water supply to different branches of the national economy. When almost all available surface water resources are involved in the national economical production, the optimal use of aquifers' fresh groundwater resources are currently playing pivotal role. That is the reason that the interest in the impacts of climate change on groundwater resources in Azerbaijan has developed greatly. This paper examines the scientific and technical aspects of evaluating the fresh ground-water resources formation in the hydrogeological structures, such as deposits in the mountainous regions, foothill and intermountain plains. It also investigates the role of the climatic factors and impacts of climate change on groundwater resources.

The Global Climate Change Impact on Water Resources of Armenia

Abstract The global climate change impact on water resources of Armenia is shortly reviewed. The mountainous character of Armenia causes the great differentiation in landscape types, as well as geological characteristics, climate, soils and water resources. The present day Armenia is disposed to significant ecological risks and becomes a country which economy is based on the intensive use of natural resources which eco security vulnerability is continually increasing. It is noted that the strategy of ecological security is based on the defensive, adaptation, cooperative and other approaches but the country needs to have ecological security concept based on the ecological ideology in beforehand. We highlighted in this presentation that the reduction of water reserves will coincide with the growth of the demand on water resources, since due to the climatic peculiarities namely due to the high air temperature the households will require more potable water and the needs of agriculture in...

Conclusions a strategy for plant improvement and management to exploit the plants drought response capacity

We have suggested above that it may be possible to use deficit irrigation to exploit the plant's long-distance signalling networks to enhance WUE in agriculture and to increase reproductive crop quality, in part by restricting vegetative crop development and the commitment of resources to this end (Yang et al., 2001 Davies et al., 2002). As soil dries, shoot water status can be sustained by signalling-induced restrictions in stomatal aperture (e.g. Mingo et al., 2003 Sobeih et al., 2004) (Figure 5.4). If as an alternative approach for different circumstances where we want to sustain vegetative growth we can develop genotypes that do not produce chemical leaf growth inhibitors as soil dries or have leaf growth processes that are insensitive to these signals, then we can perhaps also sustain biomass accumulation and yield of vegetative plant parts when water supply for agriculture is restricted. This strategy is dependent on identifying the different chemical signals that limit both...

Box 83 Drought in the Amazon

In the dry season of 2005, an intense drought affected the western and central part of the Amazon region, especially Bolivia, Peru and Brazil. In Brazil alone, 280,000 to 300,000 people were affected (see, e.g., Folha, 2006 Socioambiental, 2006). The drought was unusual because it was not caused by an El Ni o event, but was linked to a circulation pattern powered by warm seas in the Atlantic - the same phenomenon responsible for the intense Atlantic hurricane season (CPTEC, 2005). There were increased risks to health due to water scarcity, food shortages and smoke from forest fires. Most affected were rural dwellers and riverine traditional subsistence farmers with limited spare resources to mobilise in an emergency. The local and national governments in Brazil provided financial assistance for the provision of safe drinking water, food supplies, medicines and transportation to thousands of people isolated in their communities due to rivers drying up (World Bank, 2005). also affected....

Variability in water resources and plant productivity

6.3.1 Temporal variability in water resources Table 6.1 NPP, annual water supply (precipitation + irrigation) and WUEe, i.e., the quotient of biomass production to water supply in a eucalypt plantation in Furadouro, central Portugal, 6 years after planting* (adapted from Madeira et al., 2002) Table 6.1 NPP, annual water supply (precipitation + irrigation) and WUEe, i.e., the quotient of biomass production to water supply in a eucalypt plantation in Furadouro, central Portugal, 6 years after planting* (adapted from Madeira et al., 2002) Water supply (mm)

Human Food and Water Shortages

In drought-ravaged Moyale, Ethiopia, cattle are led to one of the few remaining watering holes in the region. This lack of water, along with other climate changes, can cause a decline in food production, affecting the lives of millions of people. suffer from drought and reduced rainfall. With the world's population rapidly increasing, these problems could become very serious, producing widespread water shortages and more hunger and malnutrition, especially for people in less developed areas. According to the IPCC, hundreds of millions of people in Africa and Latin America will not have enough water to live in less than twenty years, and by 2050, hundreds of millions in Asia could face the same situation. By 2080, water shortages could threaten a total of 1.1 billion to 3.2 billion people.

Plant communities facing drought

Adaptation to semi-arid environments, namely in the Mediterranean, may be used as a paradigm for the range of plant traits adaptive to water scarcity. In Figure 6.3a, plants of group I have drought-avoiding behaviour without photosynthetic active parts during dry periods but survive in a resistant form. These are a majority in the flora of most semi-arid and arid environments (e.g. annuals, chamaephytes). Another extreme is plants of group II, which are water spenders without tolerance of dehydration, exploiting specific habitats that permit access to water during most of the year. The other groups in Figure 6.3 consist of 'drought persistent' (i.e. perennial plants that maintain some photosynthesis during the dry periods) according to Noy-Meir (1973). Some of these are true xerophytes, but others may be very vulnerable to climate change such as the lauroid schlerophyllous (group V), which are relicts from the Tertiary, such as Arbutus and Myrtus, that may be eradicated if rainfall...

Species interactions with limiting water resources

Species coexistence in a situation of limiting water resources implies either avoiding interactions (niche segregation) or allowing some interaction (niche overlap). For example, the coexistence of different functional types regarding water resources enables plant communities to occupy a larger amount of physical space, exploring more resources (McConnaughay & Bazzaz, 1992). The exploitation of spatially and or temporally distinct water resources by plants allows the coexistence of different species and life forms in environments where water is scarce (Noy-Meir, 1973 Reynolds etal., 2004).

Droughts and wildfires

Fire is a natural component of many ecosystems. Often, it is the fire regime (frequency, intensity and timing) rather than drought that determines primary productivity as well as plant community (Pyne, 1997 Bond et al., 2005). Nevertheless, dry weather enhances the risk of biomass burning. For example, the severe drought of 1994 that damaged large amounts of woody plants in central and southern Spain Vegetation fires are always possible because plant biomass is a good fuel in our oxygen-rich atmosphere. Live biomass, however, does not burn easily because it has a high moisture content. Drought interacts with fires, increasing dead branches and leaf shedding. These materials (dead biomass or necromass) represent the fine fuels, which once dehydrated in hot and dry weather, become highly inflammable and increase the risk of fire. Although drought and wildfires share common causes, it cannot be concluded that more or larger fires will occur in more arid regions. For fires to occur and...

Adaptation and Water Resources

Abstract Adaptation to climate change in the water sector, especially changes in water management practices, will have a very significant impact on how future climate affects the water sector. The chapter starts out by describing the range of adaptive options that are available to water managers faced with changing circumstances. One classification distinguishes between supply-side and demand-side options. Another classification scheme proposed here distinguishes between 1) technological, 2) behavioural, 3) economic and 4) legal adaptive measures to manage and extend water resources. The chapter summarise these adaptive options. It assumes that the relative merits of one adaptive technique over another can be characterized in terms of the benefits and costs of the adaptation, across a spectrum of no effect (no adaptation or wrong choice of adaptation) to perfectly effective (adaptation sufficient to eliminate all effects of climate change) at an optimal level of cost effectiveness....

Figure 72 Grain production and scale of drought in the RSFSR 19541965

Sown area not affected by drought, dry in Kazakhstan and Western Siberia as well as in many regions of the Russian Federation (Figure 7.2.). Other key agricultural regions of the USSR, such as the Ukraine, suffered from severe droughts in 1954 and 1960. Weather did little to help Khrushchev's agricultural projects. One Soviet report evaluates 1960 to 1965 as the worst in Kazakhstan in terms of climate in the period 1946 to 1975 (Agroklimatichesky prognoz, 1978). Evidently the weather was not the only factor in the colossal losses of harvests in the virgin lands in those dry years, as inappropriate methods of cultivation (which were good in wetter conditions) exposed soils to wind erosion in the dry steppes of Kazakhstan and Western Siberia. Already in the first year of the campaign, 1954, there was a drought in eastern and southern parts of the Ukraine. In this region the large losses of grain were reported to be caused exclusively by the dry autumn weather of 1953 and then by drought...

Drought Climatology Of The Great Plains

Historical climate records for the Great Plains provide only a brief snapshot of the drought climatology for the region. For most portions of the region, climatic records cover the period since about 1900, and at only a few locations. To learn more about the occurrence and patterns of drought before that time, tree-ring data can be used to reconstruct the drought history of the region. These data provide insights into past climates extending back many centuries. Figure 1 is adapted from the work of Weakly (1965) for western Nebraska. His work was based largely on tree rings from Red Cedar for a 748-year period, from 1210 to 1958. The results of his study showed the occurrence of 21 drought periods of 5 years or more duration. The most remarkable of these drought periods was from 1276 to 1313, a period of 38 years. However, the average duration of the droughts was 12.8 years. A similar study was conducted in northern and southern Texas by Stahle and Cleaveland (1988) for the period...

Droughts and arid zones

On a global level, the area affected by droughts is likely to increase due to a reduction in (summer) rainfall combined with increased evaporation (Sheffield, 2008). Especially in subtropical regions and the Mediterranean, reduced rainfall is predicted to lead to more frequent and more intense droughts. By the end of the 21st century, the land surface affected by extreme droughts at one time could increase by 10-fold to 40-fold (Bates et al, 2008). The regions most affected by increased droughts will be the Mediterranean, Central Asia, Central America, and Southern and West Africa (Sheffield, 2008). The southern parts of the US and Australia - already regularly affected by droughts - are likely to see more frequent and more severe droughts. Increased droughts will cause significant problems for the water resources of large urban areas. For example, in Australia, almost all major urban centres will face reduced water availability and will therefore need to look for alternatives to...

Climate Change Impact on the Water Resources

According to climate change vulnerability assessment for water resources sector, reduction of outflows in the country is primarily caused by the climate change (Fig. 23.2) 9 . Current overall annual water demand is 2.3 x 106 m3 mil and projected for the year 2020 is 3.5 x 106 m3. On the other hand, developed scenarios for climate change impact on the water resources indicate that

Cold Drought Wetwildfires

Global warming will also have a significant impact in major urban areas. In many cities, the existing infrastructure (water supply, communication systems, energy delivery, and waste disposal) is aged, worn out, and has not been well maintained. In its weakened state, the stresses from global warming (such as drought, flooding, extreme weather) could be more than the systems can handle, causing major emergencies. Other stresses in urban areas that may also be affected are crime, chronic air quality problems, and inadequate power supply to meet peak energy demands. One positive aspect is that if winters are less severe, there will be fewer winter stresses and casualties. According to the U.S. Global Change Research Program, the major potential consequences of global warming include the impacts of rising sea level and elevated storm surges on transportation systems, increased heat-related illness and death associated with temperature extremes, increased ground-level ozone pollution...

Transboundary Water Resources

Regarding shared groundwater resources, the Prespa - Ohrid lake system and Lake Dojran are examples of a groundwater - surface water interaction with influence on the catchment environment. In the last decade, dramatic decrease of the water surface level in lakes Prespa and Dojran has occurred. Dojran Lake, being a shallow warm-water lake experiences extreme pressure from its environment, because three quarters of the volume of water disappeared in the period 1988-2002. Some recovery is noted due to two wet years and the construction of supplementary supply system from wells in Gjavato region. Prespa Lake and Ohrid Lake are hydraulically connected through karstic massif of Galicica Mountain. Exploration of this connection is necessary in order to re-establish the water balance in the catchment. There is a requirement for a general planning and management of shared water resources in the region. Regarding Prespa and Ohrid Lakes, several projects are already under way. Regarding Lake...

Droughts vines and frost fairs

Benson, L. et al. (2007) Anasazi (pre-Columbian Native American) migrations during the middle-12th and late-13th centuries - were they drought induced Climatic Change, 83, 187-213. Cook, E. R. et al. (2007) North American drought Reconstructions, causes, and consequences. Earth Science Reviews, 81, 93-134. Gill, R. B. (2000) The Great Maya Droughts Water, Life and Death. University of New Mexico Press, Albuquerque. Meko, D. M. et al. (2007) Medieval drought in the upper Colorado River Basin. Geophysical Research Letters, 34, doi 10.1029 2007GL029988. Stine, S. (1994) Extreme and persistent drought in California and Patagonia during medieval time. Nature, 369, 546-9. Woodhouse, C. A. et al. (2006) Updated streamflow reconstructions for the Upper Colorado River Basin. Water Resources Research, 42, doi 10.1029 2005WR004455.

Drought And Desertification

The latest report of the Intergovernmental Panel on Climate Change predicts increased water shortages in Africa (74 to 250 million people affected in 2020) and Asia. Case studies, however, bring to light a contrasting picture of the consequences for migrations of these kinds of evolutions. The effect of a lack of drinking and irrigation water on migration is actually less sudden than that of hurricanes and floods, and it only generates progressive departures. On one hand, there are many well-known cases of mass population departures following droughts, in particular in Africa (Sahel, Ethiopia) with an impressive figure of one million displaced persons during the drought in Niger in 1985, but also in South America (Argentina, Brazil), in the Middle East (Syria, Iran), in central Asia, and in southern Asia. On the other hand, many researchers strongly rela-tivize the possible direct link existing between drought and emigration by highlighting the fact that the latter, in general, is the...

Increasing Vulnerability To Drought

Since the earliest historical times, drought has been a major hazard in northwest Africa. Historical surveys of drought and other natural calamities have determined that there were 49 major drought-related famines in Morocco during the period from the late ninth century to the early 1900s (Bois, 1957) and at least 26 such episodes in Tunisia from around ad 100 to the late 1800s (Bois, 1944). While the drought hazard has perhaps always existed in northwest Africa, this hazard has been increasing during the present century (Swearingen, 1992, 1994, 1996a). It has been increasing primarily due to two key processes (1) expansion of cereal cultivation to drought-prone rangeland and (2) reduction of fallow. During the colonial period, these processes were fostered by large-scale land expropriation, by the dislodging of peasants to marginal lands, by a cereal policy offering high crop prices and other incentives, by agricultural mechanization, which facilitated the mining of marginal areas...

Field Research To Assess Linkages Between Human Activities And Drought

To help assess the linkages between human activities and drought in northwest Africa as well as the region's increasing vulnerability to drought, the authors organized an extensive field research project in Morocco during the early 1990s. A project team led by one of the authors (Bencherifa) intensively interviewed farmers about farming practices and drought-coping strategies. These interviews were conducted in three different regions of Morocco the Chaouia (a subhumid region), the northeast, usually referred to as Maroc oriental (a semiarid region), and the Chichaoua (an arid region). The research team surveyed a total of 335 households or production units. The survey consisted of a series of six questionnaire interviews, which were administered orally to the same household units over a period of nearly 2 years, from 1992 to 1994. The interview protocol was intended to capture information about dynamic responses of producers to specific climate conditions, including both drought and...

Global Warming and Future Droughts

The scientists at GISS completed research in February 2007 linking future global warming with droughts in certain parts of the world, including the southwestern United States. They used records of the Sun's output in a model to illustrate how a climate dominated by greenhouse gases would ultimately change rainfall patterns. What they found was that the same areas that experienced droughts in ancient times would experience them again. One of the consequences of global warming is drought. This region in Utah has already experienced drought conditions, leaving the reservoir at lower than normal capacities for the past two years, as seen by the exposed shoreline several feet above the present waterline. Drew Shindell, GISS team leader, said that there is already evidence that some rainfall patterns may be changing. Examples can be seen in North Africa, the Middle East, and the Mediterranean. If these trends continue, in a couple of decades there could be serious water resource challenges...

Using Numerical Modeling for Assessment of Pollution Probability of Drinking Water Resources in Borjomi Region Southern

Abstract Borjomi mineral waters field is a source of famous mineral water, which is exported to dozens of countries and forms a significant part of budget of Georgia. Currently, in connection with construction of Baku-Tbilisi-Ceyhan pipeline by British Petroleum (BP), serious concerns arise with respect to vulnerability of water supply of the city of Borjomi to possible oil spills related to operation of the pipeline. In this paper, we consider mainly the interaction between surface water and groundwater of the Bakuriani-Borjomi lava flow and the possibility of their pollution with hydrocarbons in case of oil spilling. In order to define the possible pollution propagation, we apply stable isotope technology and other modern hydro-geophysical methods that we have created. Keywords Water resources Numerical model Pollution Georgia

Figure 94 Grain production and intensity of drought in the RSFSR 19761990

Sown area not affected by drought, Some Western experts believe that the weather continued to be the dominant variable in Soviet agricultural production in this period. In 1978, Severin and Carey predicted that relatively favorable weather in the late 1970s would be reversed in the next years, bringing many problems for Soviet agriculture (1978). This did, indeed, happen. The second half of the 1970s was relatively good but the first half of the 1980s seemed to be one of the worst periods in terms of climate (Figure 9.4.). Major problems for Soviet agriculture were caused by large-scale droughts. Figure 9.4. shows that the fluctuation in grain production evidently correlated with the proportion of crop area affected by drought (this area is determined by the Hydrothermal Coefficient of Seljaninov). All the major drops in grain production in 1979, 1981, and 1984 correspond to the occurrence of severe droughts. Those of 1979 and 1981 followed that of 1975 in terms of intensity, while...

Multidecadal Drought Cycles in South Central New Mexico Patterns and Consequences

Extreme, regional droughts are the most common form of disturbance in semiarid ecosystems typified by relatively slow recovery rates. Drought-driven impacts can include regionally synchronized insect outbreaks, wildfires, and tree mortality (Swetnam and Betancourt 1990), as well as disastrous failures of agriculture, silviculture, and livestock production (Mainguet 1994). Drought conditions, accompanied by anthropogenic land mismanagement, have led to subsequent invasions of grasslands and farmlands by woody shrubs and nonna-tive forbs and grasses, contributing to the modern desertification process manifested in many parts of the world (Archer et al. 1988). In the American Southwest, the drought of the 1950s was one of the most severe climate events of the past millennium because of wide ramifications for the region's ecology (Herbel et al. 1972 Swetnam and Betancourt 1998), water resources (Thomas 1963), and economy (Regensberg 1996). As human population and resource needs increase...

Causes Of Droughts In South Africa

Having described the pattern of rainfall-producing systems in the country, attention now focuses on some of the causes of periods of insufficient rainfall and droughts. The forcing mechanisms for droughts are well documented for the southern African region (see, e.g., Tyson, 1986 Mason and Jury, 1997 Lindesay, 1998 Tyson and Preston-Whyte, 2000). Much of the recent research in the country has focused on the prolonged droughts of the last two decades (namely the 1980s and 1990s) Tyson and Dyer, 1978 Dent et al., 1987 Jury and Levey, 1993 Alexander, 1995 Mason and Jury, 1997 Lindesay, 1998 Landman and Mason, 1999). Rainfall variability for the country has been associated with atmospheric circulation configurations and interchanges in easterly and westerly circulations, the interactions between tropical and temperature systems, and the variation in pressure patterns over Marion and Gough Island (summarized in Tyson, 1986 Lindsay, 1998). Prolonged heat waves and droughts are linked, in...

Assessing the Impact of Climate Change on Groundwater Resources Using Groundwater Flow Models

Abstract Climate change is a potential stressor of groundwater resources and its effects on the availability of groundwater need to be understood and determined. The impacts of climate change on groundwater systems are conceptually known, however in the context of climate change impact assessment there has been little research conducted on groundwater compared to surface water resources. One of the tools used to quantify the effects of climate change is to use groundwater flow models in conjunction with downscaled GCM (global circulation model) results and groundwater recharge estimation. The purpose of this study is to present an overview of groundwater modeling approaches to assess the impacts of climate change on groundwater resources. Basic requirements, challenges and different approaches to overcome them are presented. The principal challenge of any climate change impact study is the downscaling of GCM results to the basin scale. Furthermore, the estimation of the impacted...

Study of sustaining groundwater resources through percolation ponds during droughts in India

The vagaries of climate change are already being felt in many countries including India. Droughts and floods have perhaps become more common. The time series of rainfall data for c. 100 years in a semi-arid region of India shows (Fig. 1) that every fourth year is a drought year and every seventh year is a year of surplus water causing floods. Thus it becomes imperative for a country like India, situated in the monsoon region (other monsoon countries include Korea, Philippines, China, Japan, Bangladesh, Pakistan, Sri Lanka, Malaysia) to develop adaptive measures to counter the climate changes. Drought year (every 4th year on average) Fig. 1. Rainfall pattern in Nalgonda district (Andhra Pradesh, India) for the last 100 years (1901-1996) showing drought every fourth year and excess rainfall in every seventh year.

Efficiency of Water Supply Assessment

Scientific basis for efficiency of water supply assessment is the empirical dependence of crop capacity on water consumption under different climatic regions. Under the condition of water resource deficiency, low water and land efficiency, it is suggested to take into account the sufficiency of water supply not only during the vegetation period but also its distribution within this period (that is, the regime of crop irrigation), and also the mineralization of irrigating water, which is not done when conducting the present cadastre. Efficiency of the water supply assessment for an irrigated area is calculated for every farm area. It consists of an average assessment over 3-5 years of actual water infiltration for crops conforming to the conditions of maximal crop growing. The irrigated area is considered supplied with water if 9.Insufficient water supply of irrigation sources 7.The rise of water supply Under the condition of water resource deficiency and in the presence of large areas...

Impact Of Climate Change On Hydrology And Water Resources

One of the major impacts of global warming is likely to be on hydrology and water resources, which in turn will have a significant impact across many sectors of the economy, society, and environment (Figures 11.2 and 11.3). Characteristics of many ecosystems are heavily influenced by water availability. Water is fundamental for human life and many activities, in- FIGURE 11.2. Impact of climate change on water resources and agriculture FIGURE 11.2. Impact of climate change on water resources and agriculture Future climatic changes in the Nile River basin would be significant and possibly severe. For example, with 4 C warming and a 20 percent decrease in precipitation, Nile River flow decreases 98 percent. This represents a significant reduction in water supply (Gleick, 1993,1998). Based on the results of the river flow responses, climate variables alone can cause a 50 percent change in runoff in the Gambia River catchment. In general, a 1 percent change in rainfall will result in 3...

Definition Of Drought

The definition of drought is not very simple, and the question What is drought continues to pose a problem (Sivakumar, 1991). This is because drought could mean different things to different people, and there are probably as many definitions of drought as there are users of water. In general, a drought is when a shortfall in precipitation creates a shortage of water, whether it is for crops, utilities, municipal water supply, recreation, wildlife, or other purposes. According to a WMO definition (Bogardi et al., 1994), drought is a sustained, extended deficiency in precipitation. Operational definitions of drought vary from place to place and are crucial to identify the beginning and intensity of drought. There are three main types of drought meteorological, agricultural, and hydrological (National Drought Mitigation Center, 1996c). 1. Meteorological drought is an expression of rainfall departure from normal over some period of time. Meteorological drought definitions are usually...

Will Human Civilization Face the Exhaustion of Water Resources Due to Global Change

The climate had always been changing and will continue to evolve in the future. So far the only acceptable conception has been based on the outputs of IPCC 12 , which declare that warming up of the Earth is caused by anthropogenic activities -specifically by emissions of carbon dioxide. But a series of scandals disclosed a specialized handling of the primary data so that the seriousness of the so far achieved results was challenged or even damaged. Nevertheless, the ever present question, which the public should ask with regard to climate change is, whether the planet will ever run out of water and similarly if fossil fuels would ever be exhausted. Therefore, to simply compare the exploitation of water resources with deposits of crude oil, coal and earth gas is evidently not correct. The volume of water existing on the Earth is stable and is estimated to attain 1,386,100,000 km3 13 , and has never changed. Nevertheless, due to great dynamics of water the spatial distribution of water...

Optimization offarm technologies and water resources

It is well known that on a global scale water is probably the most limited resource for agricultural production and directly sensitive to climate variability. Water resources can therefore vary strongly from year to year and within a single year. Extreme precipitation events and floods can be as devastating as droughts (Rosenzweig et al. 2002 Chang 2002), and these extremes could increase under climate change, depending on the region. Extreme precipitation can further lead to nitrogen leaching on sandy soils, which might be accelerated under increasing climate variability in more humid regions (Wessolek and Asseng 2006) and have implications for agricultural land use and management for groundwater recharge harvesting, for example in northern Germany. However, water shortage and droughts are the most important devastating factors for agriculture and food production because of their large spatial extension, especially in many subtropical regions and developing countries. Over the...

Impacts Of Droughts In South Africa

Drought impacts, however, are not the result only of insufficient rainfall or searing temperature. In most cases, drought impacts are the outcome of the interaction of a number of social and other human factors that can heighten the vulnerability of communities and various exposure units (e.g., vegetation) and reduce resilience of society and ecosystems to the natural hazard (Dilley, 2000 Vogel et al, 2000). As a result of these components of drought, a number of impacts are recorded. The scale of these impacts also varies and can be tracked at various levels (e.g., regional, national, community, and household) of agricultural production. For example, production declined as a result of the 1980s and 1990s droughts in southern Africa. Harvest failures of between 30 and 80 below-normal across the Southern African Development Community (SADC) region were recorded. Cereal production in the SADC countries dropped to less than 50 of the annual requirement in 1992, and the cost of imported...

Harrison 1986 Simulating Drought In Sa Reference

Abrams, L., Drought policy water issues, The African Water Page, http www.african- Forum on Drought, Secretarial and Ops Room, Johannesburg, October 8, 1992. Adams, L., A rural voice, strategies for drought relief, Indicator S. Afr., 10(4), 41-46, 1993. Alexander, W. J. R, Floods, droughts and climate change, S. Afr. J. Sci., 91, 403 08. Association for Rural Advancement (AFRA), Drought Relief and Rural Communities, Special Report No. 9, AFRA, Pietermaritzburg, 1992. Ballard, C, Drought and economic disasters South Africa in the 1980s, J. Interdiscipl, Hist., 17, 359-378, 1986. Bhalotra, Y. P. R, The Drought of 1981-1985 in Botswana, Department of Meteorological Services, Ministry of Works and Communications, Gaborone, Botswana, 1985. Bratton, M, Drought, food and social organization of small farmers in Zimbabwe, in M. Glantz (Ed.), Drought and Hunger in Africa Denying Famine a Future, Cambridge University Press, Cambridge, 1987, pp. 213-244. Bruwer, J. J, Drought policy in the...

An Overview of the Global Water Situation

According to the International Water Management Institute (IWMI), one in three people globally endures some form of water scarcity, one-quarter of the world's population lives in areas where water is physically scarce, and over one billion people live where water is economically scarce, or places where water is available in rivers and aquifers, but the infrastructure is lacking to make this water available to people.'' Fig. 1 shows a United Nations history of global water scarcity since 1950, and a projection to 2025. The World Water Institute states that water scarcity is not a factor of absolute quantity rather, it is a relative concept comparing the availability of water to actual use. In the United States and Europe, the average individual uses between 200 and 600 liters of water per day (UN - Coping with Water Scarcity, 2007 World Water Day, http www.unwater.org wwd07), compared to the 20 liters deemed to be the minimum daily requirement for drinking, washing, cooking, and...

Drought Types and Vulnerability

All types of drought originate from a deficiency of precipitation (Wilhite and Glantz 1985). When this deficiency spans an extended period of time (i.e., meteorological drought), its existence is defined initially in terms of these natural characteristics. However, the other common drought types (i.e., agricultural, hydro-logical, and socioeconomic) place greater emphasis on human or social aspects of drought, highlighting the interaction or interplay between the natural characteristics of the event and human activities that depend on precipitation to provide adequate water supplies to meet societal and environmental demands (Fig. 2.1). For example, agricultural drought is defined more commonly by the availability of soil water to support crop and forage growth than by the departure of normal precipitation over some specified period of time, ttere is not a direct relationship between precipitation and infiltration of precipitation into the soil. Infiltration rates vary according to...

Important Roles of the DRE Binding Proteins During Drought and Cold Stresses

Yeast One Hybrid

Signal transduction pathways between initial dehydration stress signal and gene expression. There are at least four signal transduction pathways two are ABA dependent (I and II) and two are ABA independent (III and IV). Protein synthesis is necessary for one of the ABA-dependent signal pathways (I). ABRE is involved in one of the ABA-dependent pathways (II). In one of the ABA-independent pathways, DRE is involved in the regulation of genes not only by drought and salt but also by cold stress (IV). Another ABA-independent pathway is controlled by drought and salt, but not by cold (III). Fig. 20.2. Signal transduction pathways between initial dehydration stress signal and gene expression. There are at least four signal transduction pathways two are ABA dependent (I and II) and two are ABA independent (III and IV). Protein synthesis is necessary for one of the ABA-dependent signal pathways (I). ABRE is involved in one of the ABA-dependent pathways (II). In one of the...

The basis of drought contingency planning

Drought planning and water crisis management needs to be proactive, is is largely because overall policy, legislation, and specific mitigation strategies should be in place before a drought or water crisis affects the use of the country's water resources. Bruins (2001) provided the basic elements involved in the development of proactive drought contingency planning and their respective relationships, ese basic elements (Figure 24.1) involve drought risk analysis, drought impact assessment, and drought scenarios. Assessments have to be made of the impact of drought on the various water resources, economic sectors, population centres, and the environment. Different types of drought should be considered in the impact assessment studies. Drought scenarios have to be calculated on the basis of available information, including development of a frequency and severity index. From this, drought risk assessment can be investigated, primarily on the basis of meteorological data but may also...

The Worlds Diminishing Freshwater Supply

On a global scale only about half of the world's population has a connection to a piped-water supply in the home, whereas 30 percent rely on wells or local village pipes, and about 20 percent have no access at all to clean water. World population is expected to grow by another 50 percent (another 3-4 billion people) in the next 50 years, so huge investments are needed to maintain the existing water supply infrastructure and develop new supply networks. As population grows and water supplies remain the same or diminish, it is expected that in the next 10 years about half the world's population will not have access to clean drinking water. Most of those without access to clean water will live in Africa, south and Central America, and southeast Asia. Many of the countries of the Middle East face a different prob-lem an extreme paucity of water of any kind. many of these countries have other economic resources such as petroleum, and will have to invest in desalination to meet the needs of...

Water Supply and Wastewater Management in Antiquity

Management Antiquity Images

In Hellenistic and Roman times, several water supply systems were constructed for Pergamon castle, which is situated on a rock with an 800 m long plateau, at a height of nearly 300 m over the town situated below it. We are here only interested in one of these systems the Madradag pipe 2 constructed during the rule of Eume-nas II (197-159 BC Garbrecht 1987). This pipe had a length of 42 km and started in the Madradag mountains at a height of 1230 m, that is 900 m higher than the rock of Pergamon. Three valleys had to be crossed and afterwards the Pergamon rock had to be climbed. Therefore, the pipe had to be operated under pressure. This was an extremely demanding requirement for the quality of pipe manufacturing, laying and sealing. The difference in the height of 900 m (from source to castle) corresponding to a pressure drop of 90 bar (9 MPa) alone for the nonflow-ing water column. Therefore, very stringent requirements had to be met. The pipes 1.1 Water Supply and Wastewater...

Water Supply and Wastewater Management in the Medieval

Monasteries founded by Cistercians, Premonstratensians and Benedictines in Europe during the 12th and 13th centuries were exemplary business undertakings for that time. Besides the monks and the abbot, numerous lay persons worked and prayed there, all requiring a reliable source of water. Frequently, a monastery was placed near a river and a ditch was dug, which was laid with a necessary gradient through the area of the monastery. Figure 1.4 presents a system for water supply and wastewater discharge as a fundamental concept (Bond 1991). Fig. 1.4 Fresh water supply and wastewater discharge in monasteries (Bond 1991). Fig. 1.4 Fresh water supply and wastewater discharge in monasteries (Bond 1991). 1.2 Water Supply and Wastewater Management in the Medieval Age 5 First, the water flowed slowly through two sedimentation basins to a distribution house crossing the main ditch of the monastery. Pipes made either from tree trunks, ceramic material or lead were used for this purpose. From the...

Long Term Effects of Drought on Ecosystems

Several studies characterize the ecological effect of the drought of 1988. Tilman and Downing (1994) provided documentation of drought effects on plant communities other than those in agriculture. They characterized the influence of the 1988 drought on plants at the Cedar Creek LTER in Minnesota, and they measured the effects of drought and the dynamics of recovery from drought against a known baseline. Indeed, it was not until 1993, the fifth year after the 1988 drought and the twelfth year of the Cedar Creek LTER, that the effects of the drought on the species richness in successional grasslands were no longer discernible. However, the effects of the 1988 drought were still clearly evident in the oak savanna complex in 1993. About 30 of mature pin oaks died during the drought, compared to only 10 of bur oaks. Most of these dead trees are still standing. Tilman and Downing (1994) concluded that this major shift in oak species composition and reduction in oak canopy cover that will...

Drought caused by changes in Global Atmospheric circulation

Drought Image Satellite Iran Map

Global oceanic and atmospheric circulation patterns undergo frequent shifts that affect large parts of the globe, particularly those arid and semiarid parts affected by Hadley Cell circulation. One of the better known variations in global circulation is known as the El Nino-Southern Oscillation. Fluctuations in global circulation can account for natural disasters, including the Dust Bowl days of the 1930s in the U.S. plains states. Similar global climate fluctuations may explain the drought, famine, and desertification of parts of the Sahel and the great famines of Ethiopia and Sudan in the 1970s, 1980s, and mid-2000s. Much of Africa, including the Sahel region, has become increasingly dry and desert-like over the past 100 years or more, and any attempts to restart agriculture and repopulate regions evacuated during previous famines in this region may be fruitless and lead to further loss of life. develop. The position of the polar front and extent...

Groundwater regime variability during the 19821994 drought period

The orographical, climatic and hydrological conditions influence groundwater occurrence, recharge intensity and regime. Our previous studies concerning the drought period in Bulgaria confirmed the sensitivity of karst springs and shallow groundwater to climate variability (Orehova & Bojilova 2001 Gerassimov et al. 2004a). For these studies the examples of springs and observational wells from the NHGN were used. The impact of the 1982-1994 drought period on groundwater was observed all over the territory of the country. The consequences of drought for the springs were comparable 20-30 reduction of discharge. The results are similar for the springs draining karstic massifs of different geological ages Precambrian marbles, Triassic dolomite and limestone, Upper Jurassic and Cretaceous limestone. Table 2. Statistical structure of discharge (h, mm) and precipitation (P, mm) of the drought period 1982-1994 Table 2. Statistical structure of discharge (h, mm) and precipitation (P, mm) of...

Meteorological Indicators Of Drought

Drought conditions are basically due to a deficit of water supply in time and or space. The deficit may be in precipitation, stream flow, or accumulated water in storage reservoirs, ground aquifers, and soil moisture reserves. In describing a drought situation, it is important to understand its duration, spatial extent, severity, initiation, and termination. Depending on the areal extent, a drought can be referred to as a point drought, small-area drought, or a continental drought. The point and small-area drought frequency are very high but are not major sources of concern at the national scale, unless they continue for a prolonged period. When the areal extent of the drought Over time, a number of drought assessment methods have been proposed. Some methods are based on qualitative observations, some on scientific criteria, and others on actual field surveys. However, to date, no comprehensive assessment method is available that has universal appeal. Different countries use different...

Snow Hydrology And Water Resources Western United States

Seasonally snow-covered areas of Earth offer special challenges for water resources management, challenges that arise from both hydrologic and social factors. Seasonal snowpacks account for the major source of the runoff for streamflow and groundwater recharge over wide areas of the midlatitudes. For example, in the western United States over 85 of the annual runoff from the Colorado River basin originates as snowmelt. Most of this is from a few small source areas in four western states, mostly above 2700 m, which comprise only 12 of the basin area. Globally, snowmelt runoff from Earth's mountains fills the rivers and recharges the aquifers that over a billion people depend on for their water resources. Future climate variability and change are expected to result in major changes in the partitioning of snow and rainfall and the timing of snowmelt, which will have important implications for water use and resource management in these regions. It is therefore important to understand the...

Examples of Expanding Deserts and Drought Disasters

Global climate change is causing many areas on the planet that were previously experiencing temperate climates to suffer drought conditions. Drought is very different from normal desert processes. A drought is a prolonged reduction in the amount of rainfall for a region. It is one of the slowest of all major natural disasters to affect people, but it is also among the most severe, causing more deaths, famine, and displacement than most other more spectacular disasters. Drought often presages the expansion of desert environments, and regions like Africa's sub-Saharan Sahel have experienced periods of drought and desert expansion and contraction several times in the past few tens of thousands of years. At present much of the Sahara is expanding southward, and peoples of the Sahel have suffered immensely. Droughts typically begin imperceptibly, with seasonal rains often not appearing on schedule. Farmers and herdsmen may be waiting for the rains to water their freshly planted fields and...

Global water resources and ecosystems

In Fig. 4.1, the long-term average mean annual runoff (MAR) of rivers is shown. This is calculated using a global runoff model (Smakhtin, VU., Revenga, C. and Doll, P, unpublished). Between regions there is a large difference in runoff. The dark areas show high runoff and the light areas low runoff. As can be expected, high yearly runoff occurs in the tropics and the yearly runoff in the desert regions is very low. The centre of North America, Australia and central Asia are places in the world where the water resources are scarce. These are the potential hotspots when CC leads to a reduction in runoff. Ecosystems need a certain amount of water to subsist and this amount varies between regions and ecosystems. For the majority of the rivers in the world there is no recommendation on the environmental water requirement. To estimate the amount of water that ecosystems need worldwide, a modelling study is performed (Smakhtin, VU., Revenga, C. and Doll, P, unpublished). This study used the...

Drought Management And Policy Initiatives

Droughts, as shown here, are a regular feature in the tapestry of South African history but have been traditionally managed from an agricultural and conservation perspective (Union of South Africa, 1923). This focus has, however, been expanded during the past decade to include a wider group of affected communities and stakeholders. During the droughts of the 1990s, the impact of the drought on rural populations, for example, was actively monitored by various task forces that emerged from a National Consultative Committee on Drought as a result of reports of severe impacts on rural communities in the country, particularly those that had been relocated during the years of apartheid. The activities of the Drought Forum raised the profile and plight of the rural poor during droughts in South Africa and ushered in a change in drought policy (Abrams et al, 1992 Adams, 1993). Building on the experiences of the 1990s drought, a strong mitigation focus for droughts has been fostered and is...

Groundwater Resources Balance Calculation

For quantification of the fractured bedrock aquifers, water resources of the mountainous regions, the upper groundwater stream (free water exchange zone and at the same time the underground component of river runoff) and the lower ground-water stream (difficult water exchange zone) are treated separately. Qv here is a variation of the groundwater natural resources within the limits of the plans. In the long-term Qv tends to zero. The results of the general water -balance calculations of the FGWR are shown in Table 13.1. The presented results are showing that the all groundwater balance elements are derivative of a precipitation and directly related to precipitation. Climate conditions play special role in formation of the potable water resources.

Groundwater Contamination

Public Health Service has established limits on the concentrations of dissolved substances (called total dissolved solids, or t.d.s.) in natural waters that are used for domestic and other purposes. The table of Drinking Water Standards for the United States lists these limits for the United States. Many other countries, particularly those with chronic water shortages such as many in the Middle East, have much more lenient standards. Sweet water is preferred for domestic use and has fewer than 500 milligrams (mg) of total dissolved solids per liter (L) of water. Fresh and slightly saline water, with t.d.s. of 1,000-3,000 mg L, is suitable for use by livestock and irrigation. Water with higher concentrations of t.d.s. is unfit for humans or livestock. Irrigation of fields using waters with high concentrations of t.d.s. There are more than 20,000 known and abandoned hazardous waste sites in the United States. Some of these contain many barrels of chemicals and hazardous...

Potential Impacts of Climate Change on Turkish Water Resources A Review

Abstract Water resources are mainly controlled by the climate conditions. Global warming will therefore have evolving impacts on water resources and poses important challenges for sustainable development. Studies are rapidly emerging with focus on potential implications of climate change on Turkish water resources. These studies can be grouped into two major fields (1) Studies investigating the degree of climate change reflected in the past observed hydro-meteorological records, and (2) studies investigating potential future impacts of climate change on water resources. In this paper, we present a summary of the current knowledge in the area of climate change impacts on Turkish water resources with emphasis on the two major fields listed above. Overall conclusion of the review is that climate change will put additional pressure on already stressed water resources in Turkey. The credibility of water management scenarios - whether focused on maintaining ecosystems or on food and energy...

Drought Exceptional Circumstances

Drought conditions of some magnitude are present almost every year in some part of Australia because of its vast size and semiarid to arid climate. Such occurrences are a part of normal life and are not of major concern at the national level. Sustained droughts, usually lasting one to two years, possibly for three years, and extending across large tracts of the country have created great disasters. These are of relatively less frequent occurrence, and each of them has different spatial, duration, and intensity characteristics. When drought conditions are so intense and protracted that they are beyond those that can reasonably be factored into normal risk management strategies, they are termed drought exceptional circumstances (Lembit, 1995). In practice, this is a drought of such rarity and severity that it occurs no more than once in every 20 to 25 years and is more than 12 months in duration (Clark et al., 2000 Dixon, 1995). Assessment of Drought Exceptional Circumstances The...

Nonconventional water resources

If conventional resources are not usually available to cover excess or peak demands, non-conventional resources are employed. Among natural non-conventional water resources several possibilities are considered, but the usual ones are runoff water, natural brackish water, or desalinated seawater (Georgopoulou et al. 2001). Non-conventional water resources coming from the anthropic water cycle can also be used reclaimed wastewater will be considered (Asano & Levine 1998).

Future of Water Resources in Turkey

However, not all of the renewable water resources can be utilized because of economic and technical reasons. Exploitable portions of surface runoff, inflow from bordering countries, and groundwater are 95, 3, and 12 billion m3, respectively. Thus, the total of exploitable water resources amount to 110 billion m3. The projections for future water consumption would be valid on the condition that the water resources are protected from pollution at least for the next 25 years. It is imperative that available resources have to be evaluated rationally so as to provide clean and sufficient water resources for the next generation. Because of the climatic conditions of Turkey, the precipitation-flow relationships can change not only seasonally but also from year to year and natural water supply can falls to minimum levels in summer time, when the demands are at the highest levels. The country's water resources are very sensitive to climatic conditions, and droughts are generally present in...

Historical Examples Of Drought

Short-term drought occurred in many places in the world during the 20th century. western Europe, including England, experienced years of drought on a number of occasions, as did parts of the United States. South America, Africa, and Asia have also known years in which drought conditions occurred. In the 1960s, drought appeared in the northeastern United States. Winter snows failed in the western United States 1975-77. In 1976, western Europe suffered a summertime drought. In the late 1960s and in the early 2000s, parts of Africa suffered from drought. There are regions of the world where drought is normal. Some areas, such as the northeastern area of Brazil or other semi-arid regions, have regularly re-occurring patterns of drought. Drought in some areas of the Amazon basin, in 2005, was recorded as a 100-year drought. Some Brazilian scientists argued that it was due to deforestation that was pushing the Amazon rainforest to a tipping point where it would never recover as a...

Future of Water Resources and Wastewater Reuse in Turkey

Abstract Having a water potential of 1,500 m3 capita-year, Turkey cannot be classified as a water rich country. It is estimated that in 2030 the population will reach 100 million and consequently the water potential will drop down to 1,000 m3 capita-year. Considering the predictions about regional and global climate change trends these figures obviously indicate a probable water scarcity in the nearest future and the importance of efficient wastewater reuse in Turkey. In Turkey, waste-water reuse for irrigation purposes was done in the past by direct use or after mixing with river water. But, recently, more conscious wastewater reuse applications are practiced, considering the predictions and protection of water resources from pollution. In this paper, a general view of current water resources and wastewater reuse activities in Turkey are given. Also the future predictions and planned activities are mentioned. Keywords Wastewater treatment Water reuse Turkey Water resources...

IS there a drought iN Las Vegas

In the past decade the water seems to be diminishing. Lake Powell in Arizona has shrunk to half its capacity, and the Colorado River flow shrunk to a quarter of its typical rates. The Colorado River is used to supply 30 million people with water and irrigates four million acres of fertile farmland, producing billions of dollars worth of crops. The massive waterworks systems across seven states in the southwest were all built using river flow data for the Colorado River based on 20th century flow records. Now, studies of the ancient climate history in the region going back thousands of years indicate that the 20th century may have been one of the wettest on record for the region. The Hoover Dam, the California aqueduct, and cities across the region were all built during this high flow stage of the Colorado River, and water budgets for the region were calculated assuming these flows would continue. Now, precipitation is decreasing, and the historical records show that the region...

Drought as a Disturbance Regime

Severe drought has been implicated as a contributing factor to recent accelerated rates of tree mortality in the southeastern United States (Tainter et al. 1984 Starkey Relative to long-term mean ( ) -14 +17 Number of consecutive growing season droughts and aValues in parentheses for the number of consecutive growing season droughts represent the range of the deficit relative to the long-term mean. Adapted from Clinton et al., unpubl. data, 1999. et al. 1989 Stringer et al. 1989 Clinton et al. 1993). This pulse of mortality may have a long-term impact on stand structure and function (Clark et al. 2002). The structural pattern associated with drought-induced mortality (i.e., standing-dead snags) implies that important types of microhabitats are not produced. For example, species such as pitch pine that require large openings (Barden and Woods 1976) commonly associated with large-scale, wind-induced mortality or wildfire are at a distinct disadvantage. In addition, the lack of a pulse...

Global water use trends Ever increasing

Water is fundamental for all kinds of development. Human development and well-being, industrial and economic development, energy production and agriculture all rely on the availability of (often abundant) water resources. However, there are distinct differences between sectors of society, their relationship to water and the future implications that changes in availability may have. Domestic water use (drinking, sanitation and societal services) accounts for approximately 8 per cent of global water use, though at the household level it varies considerably by one's living standard (UN, 2003). In 2000 nearly 1 billion urban dwellers lived in slums and had as little as 5 litres per day at their disposal, while nearby middle- or high-income households had between 50 to 150 litres per day (UN, 2006). In 2006, according to the latest Joint Monitoring Programme report, 884 million people lack access to safe drinking water (WHO and UNICEF, 2008). This is nothing less than a scandal. A debate...

Impacts on Water Resources Users

In response, London officials abolished cesspools and made the use of water closets, drainage pipes, and centralized sewer collection systems mandatory. Over in the United States, city officials were also feeling the pressure of a populace weary of the noxious conditions associated with open sewers. In 1910, about 10 of the urban population was serviced by centralized collection systems (FWPCA, 1969). This number increased steadily in the following decades by 1940, 70.5 million persons (53 of the population) were served by them. Unfortunately, treating drinking water with chlorine and developing efficient sewage collection systems did little to help water resources users. Raw sewage deposited into streams, lakes, and estuaries was still raw sewage, whether it was discharged through an engineered wastewater collection system or through an open ditch. Collection systems just made the dumping more efficient and complete. And though chlorine proved to be a godsend for public health, it...

Molecular breeding for drought and heat

In breeding applications, molecular markers may be either diagnostic (i.e. perfect markers of a specific allele within a specific gene sequence) or putative (e.g. markers associated with or flanking a QTL that has been discovered via mapping in biparental crosses or in association panels of related or unrelated lines). Diagnostic markers are preferable as they can be used to select desired alleles in any parental or progeny line of a species under any crossing strategy. Alternatively, such markers can be used to prepare a gene for transgene (genetic modification, GM) approaches within or across crop species. QTL markers from mapping studies are not perfectly linked to genes (i.e. they are 'nearby') and are frequently difficult to transfer between crosses, unless there is substantial research investment in crossing and mapping to 'fine map' the QTL to locate markers that are within a gene. The identification of QTLs for complex traits is further confounded by substantial genotype x...

Droughts and Floods Are Likely to Increase

Drought is a complex environmental impact. It is strongly affected not only by the balance between precipitation and evapotranspiration (the sum of evaporation of water from the surface and transpiration of water though the leaves of plants) and the resulting effect on soil moisture, but also by other human influences such as urbanization, deforestation, and changes in agriculture. Additionally, historical data on drought frequencies and intensities are limited, making it difficult to unambiguously attribute severe droughts to climate change. Climate model projections indicate that the area affected by drought and the number of annual dry days are likely to increase in the decades ahead. In areas where water is stored for part of the year in snowpack, reductions in snowpack and earlier snowmelt are expected to increase the risk of water limitations and drought.

Climatological Methods forManaging Farm Water Resources

Almost all of the water available on the earth, 97 percent, occurs as saltwater in the oceans. Of the remaining 3 percent, 66 percent occurs as snow and ice in polar and mountainous regions, which leaves only about 1 percent of the global water as liquid freshwater. More than 98 percent of freshwater occurs as groundwater, while less than 2 percent occurs in rivers and lakes. Groundwater is formed by excess rainfall (total precipitation minus surface runoff and evapotranspiration) that infiltrates deeper into the ground and eventually percolates down to groundwater formations (aquifers). For temperate, humid climates, about 50 percent of precipitation ends up in the groundwater. For Mediterranean-type climates, this figure is 10 to 20 percent, and for dry climates it can be as little as 1 percent or even less. The global renewable water supply is about 7,000 m3 per person per year (present population). The per capita minimum water requirement is estimated at 1,200 m3 annually, of...

To changes in water supply in a changing climate

This brief introduction should be enough to highlight the fact that even subtle changes in the environment are likely to have significant effects on composition and functioning of natural plant communities and on the productivity of agriculture in even the most productive areas of the world. As the climate changes, it is important that we understand the basis of stress-induced changes in plant growth and functioning and if possible intervene, through plant improvement or management programmes, to sustain biodiversity of natural communities where desirable and maintain food production, particularly in some of the most water scarce, populous regions of our planet. This review highlights some of the most sensitive limitations on plant growth and functioning that are imposed by water scarcity. We also focus on the possible exploitation of some of this knowledge to help sustain the production of food under increasingly challenging environmental conditions for farmers. that have no direct...

The Global Water Situation

X 103 km3 yr (Global water budget data cited in this section are from Postel et al.1 and Gleick2). These are satisfied primarily by direct withdrawals from accessible runoff defined as the accessible flux of water flowing from the land to the ocean as either river water or groundwater. The remainder is satisfied by nonrenewable extractions from water stored in lakes and ground water aquifers. Direct withdrawals account for about 35 of the current accessible runoff of 13 x 103 km3 yr. If instream water uses such as navigation, maintenance of riparian ecosystems, and dilution of contamination are treated as claims on accessible runoff, this percentage increases to about 50 . Spatial and temporal fluctuations in precipitation, evaporation, runoff, and water quality create regions of varying water abundance and scarcity. This has the effect of making water resource management a regional rather than a global enterprise. The spatial variability of water resources can be described in many...

General observations regarding scenarios future climate and water resources

The IPCC prepared five reports, the latest of which, in a preliminary version, was released in January 2007. The conclusions of this report most relevant to water resources and groundwater are (IPCC 2007) The IPCC scenarios (global and regional) are based on the results from Global Circulation Models (GCMs), traditionally considered by the IPCC to be the most reliable tools for obtaining indications regarding the future climate (Troen 1993 Kattenberg et al. 1996 IPCC 2007). Uncertainties conspire to make the model output, a rough approximation at best, of what could happen under various assumptions of greenhouse gases emissions (Covey 2003 Friedlingstein et al. 2003 Bender et al. 2006 Hegerl et al. 2006 Schmidt et al. 2004 Masson-Delmotte et al. 2006 van Ulden & van Oldenborgh 2006 Zhang et al. 2006 IPCC 2007 Schneider 2007). Future scenario outputs may even be contradictory (Rosenberg et al. 1999 Gagnon & Gough 2005 Stephenson et al. 2006 IPCC 2007 Kripalani et al. 2007 Li et...

History Of Water Supply And Its Effects On Public Health

The urban water cycle can be divided into a water supply side and a wastewater disposal side (see Figure 1-1). The basic technological framework for the water supply side began as far back as 5,000 years ago when people from the Nippur of Sumeria, reason, bypassing the wastewater treatment side of the urban water cycle affected both water supply and water resource users.

The hydrosphere and the global water cycle

Table 2.22 Global water reservoirs (in 1018 g) and fluxes (in 1018 g yr on earth adapted from A Berner and Berner (1987), B Berner and Berner (1996), C Schlesinger (1997), D Trenberth et al. (2007). Table 2.22 Global water reservoirs (in 1018 g) and fluxes (in 1018 g yr on earth adapted from A Berner and Berner (1987), B Berner and Berner (1996), C Schlesinger (1997), D Trenberth et al. (2007).

Impact of climate change on water resources

Water is one of the main integrating factors for many environmental and economic systems in Europe. Under current climatic conditions, many areas have problems with water supply. Climate change is likely to enhance water-related stresses in these areas (8). In a warmer climate, water availability will be reduced by increased evapotranspiration. However, the response of hydrological systems depends on many factors, such as the distribution of precipitation and storage capacity. Many regions will experience a general decrease in runoff, although the change in runoff may range between -5 and +12 . More droughts are expected in southern Europe (8). The potential for winter and springtime flooding may be greater in northern, northwestern and central Europe.

Drought as Hazard

Drought differs from other natural hazards in several ways. First, drought is a slow-onset natural hazard often referred to as a creeping phenomenon (Gillette 1950). Because of the creeping nature of drought, its effects accumulate slowly over a substantial period of time, tterefore, the onset and end of drought is difficult to determine, and scientists and policy makers often disagree on the basis (i.e., criteria) for declaring an end to drought. Should drought's end be signaled by a return to normal precipitation and, if so, over what period of time does normal or above-normal precipitation need to be sustained for the drought to be declared officially over Do precipitation deficits that emerged during the drought event need to be erased for the event to end Do reservoir and ground water levels need to return to normal or average conditions Impacts linger for a considerable period of time following the return of normal precipitation, so is the end of drought signaled by...

Drought Risk Atlas

Tte goal of the drought risk atlas is to provide users with a comprehensive assessment of the history, frequency, intensity, duration, and trend of droughts over the past century on a site-specific basis, tte intent is to provide users with a tool to help them better understand and visualize their drought risk in order to make better long-term management decisions. An interactive web-based interface will allow producers, water managers, and decision makers to tap into a database containing precipitation, stream flow, and drought indices based on daily data that goes back to the late 1800s and early 1900s. Historical analyses will allow users to examine seasonal, monthly, weekly, and daily patterns, along with the spatial distribution and characteristics of precipitation and drought. Users will be able to display and print their results in table, graph, or map format. Tutorials and libraries of information explaining the results will accompany both the web-based tool and an envisioned...

Droughts

Stigter et al. (2007) have summarized contributions of the meteorological community to improved coping with drought in India supporting development efforts related to monsoon water use as a resource. Viet (2002) rates drought at a medium relative disaster rate intensity in the most vulnerable central highlands and the south of Vietnam. Changing cropping calendars and patterns appear the only solutions envisaged there in present planning exercises (Stigter et al. 2007). Sahni reports in Sahni and Ariyabandu (2003) that the High Powered Committee on Disaster Management of India has recommended that with the frequent changes in land use, irrigation development, cropping patterns and agricultural practices, it is necessary to frequently update mapping of drought prone areas for development planning. ttis Committee also concluded that currently there is no operational procedure to forecast the impending drought conditions with respect to area of impact, extent and duration. Such...

Drought

Droughts occur WHEN the rainfall in an area falls below its normal pattern for an extended period of time. If the drought occurs in a region where crops are usually not irrigated, then farmers suffer crop losses that may range from mild to severe. If the drought is extreme, the crop losses may be total, because the plants wither and die without water. The weather, which is the current atmospheric conditions locally or regionally, can develop into a pattern that seems to be stuck. In such conditions, floods or drought may occur. Meteorologists who make long-range weather predictions cannot predict droughts. However, scientists and others who study climatic conditions produced by weather patterns in an area or region over long periods of time have found that there are times in which drier weather than normal occurs and when wetter weather than normal occurs. By studying the growth patterns of tree rings, seasons of significant growth in wet years can be seen in comparison with years in...

Effects Of Drought

When droughts occur, they can have a number of negative effects. The drought can cause the destruction of plants and animals, and the deaths of vast numbers of human beings. Droughts can be the result of a failure of winter rains and snows. The absence of winter moisture can affect plants, animals, and humans. In many areas, water supplies are dependent upon winter moisture that is stored for use by farmers and cities, and may, if the drought is prolonged, create immense problems for humans. For example, Los Angeles, California, is dependent for much of its water supplies on snowmelt from the snowpack in the high Sierra Mountains in northern California. If there is a winter snow drought, it is a threat, because water Droughts are often accompanied by higher than normal temperatures. The higher temperatures cause plants to suffer heat stress. The heat stress from temperatures that may be 10, 20, or more degrees above normally occurring temperatures dry out plants so that not only...

Recent Droughts

Droughts occur in other parts of the United States with some frequency, but on an irregular schedule. They may be mild and last only a year or two. Other droughts can be prolonged and last for five, six, or more years. They range from mild, to severe, to extreme. During 2007, Georgia, Alabama, and areas of Florida suffered an extreme drought that was unprecedented. Lakes, ponds, and streams ran out of water and became dry. Wells and other sources of water were depleted, causing significant political turmoil. Besides a meteorological and an agricultural drought, the area was experiencing a hydrological drought. The water resources had not been husbanded with sufficient stewardship to make them last well during the drought. Some areas of the world, such as the Aral Sea, and a lesser extent the Caspian Sea, have experienced hydrological drought because water resources have Political disputes, in 2007, over the distribution of water by the U.S. Army Corps of Engineers from Lake Lanier in...

Water Resources

Both supply of and demand for water resources are likely to change in a warming climate. As population increases and urbanization proceeds apace, there is also likely to be greater demand for water from competing domestic and commercial users. Studies show that increased water requirements for agriculture in many regions are likely under warming conditions, and that there is potential for decadal surprises in the reliability and percentage of water demand that can be met (Figure 10.7a) (Strzepek et al., 1999 Doll, 2002). Research on water resources for agriculture in temperate areas has shown that changes in seasonality such as earlier snowmelt will likely change the filling and use of reservoirs and hence of water availability for irrigation (Figure 10.7b) (Strzepek et al., 1999). Current utilization plans for such facilities will need to be adjusted and readjusted as the decades proceed. Whereas early work on climate change impacts on agriculture tended to focus on the effects of...

Freshwater Resources

Humans and ecosystems rely on water for life. The availability of water depends on both the climate-driven global water cycle and on society's ability to manage, store, and conserve water resources. Climate change is affecting both the quantity and quality of Earth's water supplies. Already, precipitation amounts and patterns are changing, and these trends are expected to continue or intensify in the future. This creates significant challenges for water resource management, especially where current water rights and consumption patterns were established under climate conditions different from the conditions projected for the future. Moreover, climate change is not the only problem putting demands on water supplies. Growing populations and consumptive use may cause shortages in some regions. Responding to these challenges will require better data and modeling as well as a better understanding of both the impacts of climate change and the role of water governance on water resources. How...