File Name: global water resources vulnerability from climate change and population growth .zip
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This study focused on analysis of global food demand and supply situation by and , water demand-availability, impact of climate change on world water resource, food security and desalination challenges and development opportunities.
The population of the world will be 8. World cereal equivalent CE food demand is projected to be around 10, million tons in and 14, million tons in , while its production is projected to be 10, million tons in and 15, million tons in having a marginal surplus. India and China are capturing large share of global food demand. The developing country will demand more animal origin foods due to income growth in the future.
The growth rate of world demand for cereals will decline till Evidence showed that climate change will have adverse impact on world water resources and food production with high degree of regional variability and scarcity. A number of options are suggested for development of global water resource and food production. Desalination - Challenges and Opportunities.
Food and water are important for life. Global population increased many folds in the last century and will further boost by and [ 1 ]. Such large world population will be demanding for more food and water in the future.
Despite the fact that agricultural growth has been higher than the rate of population growth concerns has been raised whether the land mass of world is actually capable of supporting its expanding population by and Food security remains a relevant and priority of many nations with special emphasis on developing countries.
There is growing concern on the future demand for and supply of food in the world. The global food system is experiencing an unprecedented confluence of pressures that may increase over the years [ 1 ].
Increased food production will require greater inputs-land, water or energy, or a combination of these inputs. Thus, required increase in food production will intensify competition for land, water and energy [ 2 , 3 ]. The global agriculture is evolving with food demand of people, availability of technology and climate change.
A number of studies attempted to answer this and projected demand for and supply of key food items in various countries and assessed gap [ 4 , 5 , 6 ]. There are growing concerns on the impact of climate change on the water resources.
A number of studies assessed such impact at various country levels and food security challenges [ 7 ]. An ever increasing amount of evidence suggests that the continual increase in greenhouse gas emissions is affecting the global climate and altering the local precipitation and temperatures [ 8 , 9 ]. Climate change is expected to produce significant effects on global water resources and freshwater ecosystems [ 10 , 11 ]. The effects and intensity of climate change will vary from region to region [ 12 ].
Impact of climate on global water storage capabilities and hydrologic functions will have significant implications for water management and planning as variability in natural processes increases. This study was carried out with the objectives to examine and assess global food demand and supply situation by and , world water demand- availability scenario, impact of climate change on global water resource, food security challenges of the globe, identify challenges and development opportunities.
The study is completed based on extensive review and analysis of relevant information and literature available across various regions of the globe.
Population of the world reached to 7. China 1. World population size increased seven fold during the period — Currently, the world population is growing approximately by 83 million people annually.
Growth rates are slowing to various extents within different regions with result of the overall population growth rate decreasing from 1.
With the main driver of future population growth is the evolution of the fertility rate [ 9 ]. More than half of global population growth between now and will occur in Africa. An additional 2. Asia is the second largest contributor to future global population growth followed by Northern America, Latin America and the Caribbean and Oceania, which are projected to have much smaller increments.
In the medium variant, Europe is projected to have a smaller population in than in Medium-variant projection of population growth by major region, — Source: Ref . There is link of population growth with economic growth and food demand. According to Malthus, population growth responds to a wage or income signal that depends negatively on the size of the population in relation to the economy and its resource base [ 8 ]. Population growth is positively related with incidence of poverty.
With economic growth incidence of poverty is reduced and population growth declines as result of declining fertility rates. For example, incidence of poverty is high in Africa and growth rate of population is also high. The projected large world population in and discussed above has received a great deal of attention as an influence on world food demand [ 8 ].
Besides population growth, income growth also becomes an important driver of food demand. This dietary change puts pressure on agricultural resources since animal-based food requires disproportionately more agricultural resources including water in production [ 11 ]. Substantial efforts have been made in modeling to forecast the global supply and demand for food to the middle of the century, typically using large global agricultural models [ 12 , 13 , 14 ].
However, the projections for food output and prices vary widely across the models, depending on their underlying supply and demand specifications, choices of key parameters such as price and income elasticities and their treatments of technical change. For simplicity of estimation of projected world food demand all food items were converted to cereal equivalent food CE [ 17 ].
The drivers of cereal equivalent CE food demand are growth rate in per capita CE food consumption and population growth rate. Table 2 shows that world CE food demand increased from million tons in to million tons in Decade wise analysis of growth rate shows that annual growth rate of CE food demand declined from 2. World CE food demand is projected under strong convergence scenario to be around 10, million tons in and 14, million tons in [ 17 ].
On the supply side, CE food production is projected to be 10, million tons in and 15, million tons in The regional decomposition shows that developing countries as a group dominate the increase in food demand and that their income convergence does matter. It was that convergence by middle-income countries, especially such populous countries as India, China, Indonesia and Nigeria, is particularly important for global food demand. This is partly due to the inverted-U shaped pattern of income elasticities for aggregate food demand, with middle-income countries experiencing the largest income elasticities due to their dietary upgrading toward more resource demanding products [ 10 ].
India has the largest share of world food demand Table 4 shows projected food demand and supply of Bangladesh by and Bangladesh is self-sufficient in rice now. The projections show that Bangladesh will have a surplus rice production of 1.
On the other hand, the country will have deficits productions of wheat, potato, pulses, vegetables, meat, egg and fresh water fish amounting 0. The country is also highly deficit in well seed production. It is projected that Bangladesh will have a surplus production of rice, maize, potato, vegetable and milk by and will have deficit production of wheat, pulses, fruits, meat and fresh water fish in Almost all the increases in the consumption of cereals will come from the developing countries.
Like other developing countries with income growth food consumption in Bangladesh is slowly diversifying. The contribution to calorie intake from potato, vegetables, and animal products gradually increased between and and will continue to increase between and Figure 3. The share of calorie intake from cereals seems to be reaching a level of saturation. However, as far as rice consumption is concerned, there is no room for significant increases in average consumption even with income growth; in fact, it even started decreasing as in countries with similar consumption and economic growth patterns in Asia [ 19 ].
World average per capita rice consumption has declined after late s, following mild declines in several countries of East and South Asia and small increases in other regions. It is striking to note that the per capita wheat consumption has also declined in both the developing and the developed countries.
Food consumption demand of coarse grains as staple food in several countries in sub-Saharan Africa will increase in the next decades. With the growth in income in developing countries demand for food from livestock origin increased in the past two decades and projected to grow further by and The ARIMA forecasts show that the consumption of animal origin food meat, milk, egg and fish and non-cereal food potato, vegetables and fruits in Bangladesh will have increasing trend during — Figure 3.
Beyond the consumption of animal products will further increase Figure 4. Projection of per capita calorie intake from animal products. The demand for water originates from four main uses- agriculture, energy production, industrial uses and human consumption.
The global booming demand for livestock products is increasing the demand for water as well. Over the past half century, the area equipped for irrigation has more than doubled, total livestock production has more than tripled and inland aquaculture has grown more than fold. Accelerated urbanization and the expansion of municipal water supply and sanitation systems would also contribute to the rising demand.
Changing consumption patterns, including shifting diets toward highly water-intensive foods such as meat i. Water is important for food security, crop growth, livestock, and food markets. Lack of water can be a major cause of famine and undernourishment, especially in areas where people depend on local agriculture for food and livelihoods. OECD projected that 3. The world net-land under crops predicted to increase by some 70 million ha by The area harvested may increase by almost twice that amount as a result of increased multiple cropping and reduced fallow lands.
The projected 70 million ha increase is the result of an expansion in the countries of sub Saharan Africa and Latin America [ 18 ]. Irrigation has been an important contributor to cereal yield growth over the past decades.
World irrigated areas are currently million ha, more than twice the level of the early s. World total irrigated area is projected to expand to million ha in This expansion of around 22 million ha will be mainly in developing countries. The potential for further expansion of irrigation is limited. Many water sources of the world are degrading and creating water scarcities. Nearly one half of the irrigated area of the developing countries is in India and China.
One third of the projected increase will likely be in these two countries. The renewable water resources that would underpin the expansion of irrigation are extremely scarce in several countries.
Irrigation water withdrawals from such resources are only 6.
Water scarcity water stress or water crisis is the lack of fresh water resources to meet the standard water demand. Humanity is facing a water crisis, due to unequal distribution exacerbated by climate change resulting in some very wet and some very dry geographic locations, plus a sharp rise in global freshwater demand in recent decades driven by industry. Water scarcity can also be caused by droughts, lack of rainfall, or pollution. This was listed in by the World Economic Forum as one of the largest global risks in terms of potential impact over the next decade. The essence of global water scarcity is the geographic and temporal mismatch between freshwater demand and availability.
DOI/SCIENCE; Corpus ID: Global water resources: vulnerability from climate change and population growth.
Charles J. Find in Lib. Add to Collection. The future adequacy of freshwater resources is difficult to assess, owing to a complex and rapidly changing geography of water supply and use. Numerical experiments combining climate model outputs, water budgets, and socioeconomic information along digitized river networks demonstrate that i a large proportion of the world's population is currently experiencing water stress and ii rising water demands greatly outweigh greenhouse warming in defining the state of global water systems to
One of the most pressing global issues currently facing mankind is the increase in world population and its impact on the availability of freshwater. Recent estimates of water stocks and flows through the world's hydrologic cycle and their spatiotemporal variability illustrate the nature of current and projected water disparities throughout the world.
Water resources in the future: problems and solutions. The present water crisis has many components of an environmental, economic and social origin: overuses of water, pollution, changes in availability, and water mismanagement are some of the current problems. To cope with these problems and enhance strategies for long term management, the following programs and approaches are presented: a A watershed approach, integrating research, monitoring, data base and management; b An improved water governance system based on participation of stakeholders and the public and private sector; c Strategic studies considering water and the economy, water and metropolitan regions, water and energy; d A framework for international cooperation on shared watersheds; e An economic evaluation of water resources services surface and underground, lakes, rivers and reservoirs.
North Africa is considered a climate change hot spot. Existing studies either focus on the physical aspects of climate change or discuss the social ones. The present article aims to address this divide by assessing and comparing the climate change vulnerability of Algeria, Egypt, Libya, Morocco, and Tunisia and linking it to its social implications. The vulnerability assessment focuses on climate change exposure, water resources, sensitivity, and adaptive capacity.
This study focused on analysis of global food demand and supply situation by and , water demand-availability, impact of climate change on world water resource, food security and desalination challenges and development opportunities. The population of the world will be 8. World cereal equivalent CE food demand is projected to be around 10, million tons in and 14, million tons in , while its production is projected to be 10, million tons in and 15, million tons in having a marginal surplus. India and China are capturing large share of global food demand. The developing country will demand more animal origin foods due to income growth in the future. The growth rate of world demand for cereals will decline till
One of the most pressing global issues currently facing mankind is the increase in world population and its impact on the availability of freshwater. Recent estimates of water stocks and flows through the world's hydrologic cycle and their spatiotemporal variability illustrate the nature of current and projected water disparities throughout the world. As all such problems manifest themselves at smaller scales, a major challenge in freshwater assessments is how to handle this on different geographical scales. Increasing use of water is creating water shortages in many countries that are projected to have significant population increases in the next 25 years.
New global models provide the opportunity to generate quantitative information about the world water situation. Here the WaterGAP 2 model is used to compute globally comprehensive estimates about water availability, water withdrawals, and other indicators on the river-basin scale. Withdrawals grow elsewhere because population and economic growth will lead to rising demand for water, and this outweighs the assumed improvements in water-use efficiency. An uncertainty analysis showed that the uncertainty of these estimates is likely to have a strong geographic variability. Vorosmarty, C.
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phy of water use and availability, analyzing the. vulnerability of water resource infrastructure. (8) to future climate change, population growth. and migration, and.