Recent progress in the use of renewable energy sources to power water desalination plants

Spatio-temporal variation of drought in China during 1961–2012: A climatic perspective

Fossil fuels such as coal, petroleum, and natural gas have been used as the major sources of energy in the recent past. However, the negative environmental impacts associated with the emission of the greenhouse gases from these conventional energy sources forced to realize the importance of renewable energy resources. At the same time, the average annual exponential rate of population growth in India needs increasing amounts of fresh-water for the basic necessities. This might result in water scarcity as the overall population in India is expected to increase to 1.60 billion by 2050. It has been forecasted that, by the year 2040, India will rank 40th in the world in terms of water scarcity. To meet the rising fresh-water demand, desalination is an intelligent and sustainable option for India, which has a very long coastline measuring 7517 km. In this paper, an attempt has been made to provide a comprehensive review of water scarcity in India and suggest a possible solution, which is implementing desalination technologies coupled with renewable resources. The paper reviews the ground water scenario in India and the global desalination market. We summarize the energy consumption in various desalination processes and provide a brief outlook of the desalination techniques in India. Apart from this, desalination using non-conventional sources such as solar, wind, and geothermal energy is discussed. In addition, factors affecting the environment due to desalination and the potential counter measures are presented. This review aims to provide an awareness of the projected water crisis in India, in the coming decades, and is also aimed to help the policy makers for selecting an appropriate desalination technology.

Renewable energy integrated desalination: A sustainable solution to overcome future fresh-water scarcity in India

Variability and trend in the hydrology of the Yangtze River, China: Annual precipitation and runoff

Research on climate change impacts and related adaptation to water demand is still very limited. A review summarising the findings related to climate change impacts on water demand is carried out in this article. A water management strategy is also proposed, which would help with adaptation to growing pressure on water resources due to climate change and socio-economic development. The study reveals that climate change will increase global water demand, though this will vary widely with geographic location and climatic conditions. Water demand in agriculture will be affected more heavily than will demands in other sectors. As irrigation comprises the major portion of global consumptive water use, increased water demand in irrigation may cause severe stress on water resources. Studies suggest that water demand management or water supply management alone will not able to adapt to mounting water stress. A combination of both water supply and water demand management strategies is necessary in order to adapt to varying environmental and associated uncertainties. A case study from the Haihe River basin of China is presented, to illustrate the effectiveness of water demand management strategies used alongside water supply management in adapting to environmental changes. It is expected that the study will help guide policy responses, with the goal of mitigating the impacts of climate change on water resources.

Adaptation to climate change impacts on water demand

Water Scarcity and drought are recurrent phenomena in China. In the context of environmental change, an increasing tendency in drought frequency and severity is observed in China in recent years. Therefore, it is imperative to take necessary initiatives to reduce the impacts of drought. In this paper, an attempt is made to identify the best water management strategies to cope with droughts. For this objective the records of historical droughts and their impacts in China over the period of 1950–2009 are analyzed. It is observed that the drought affected area has increased nearly by 12 folds and the drought damaged area has increased by about 22 times in China in last 60 years. Over 87,000 reservoirs were built with a total water storage capacity of about 7,064 billion m3 to cope with droughts. However, this structural supply-based management strategy was not enough to meet the increasing water demand caused by rapid economic development and population growth. A typical relationship between socio-economic development and water resources management strategy to attain sustainability in water management is developed in this study. The relationship shows that the demand-side water management strategies can be the best option to meet the challenges posed by increased severity of drought, population growth, economic development and possible climate change. The concept is later verified through the analysis of changing pattern of water consumptions by different sectors in last 60 years.

Water resources management strategy for adaptation to droughts in China

Economic development, population growth, urbanization and climate change have led to an increasing water shortage across the globe. Ensuring water security under changing environment will be the greatest challenge for water resources managers in near future. In this paper, catastrophe theory based multi-criteria evaluation model has been proposed to assess water security under different management strategies to recommend the best water management strategy to achieve water security in the context of global environmental change. The assessment model involves future scenarios of climate change, population growth and economic development. Total 16 indicators related to climate, socio-economy and water availability and consumption have been proposed to measure water security under three management strategies viz. business-as-usual, water demand management and water supply management. The model has been applied to Yulin city of North West China to assess water security as well as to identify the water management strategy under changing environment. The results show that under business-as-usual situation the water shortage rate will reach up to 44 % by the year 2020 and up to 70 % by the year 2030 in Yulin. Water supply is required to increase by 41 % to meet the water demand under supply management strategy which is beyond the safe baseline rate. The study reveals that water demand management can reduce the gap between water supply and demand to a reasonable amount and therefore, can be considered as the most effective approach for adapting with environment change.

Catastrophe theory to assess water security and adaptation strategy in the context of environmental change

Water resources are an integral part of the socio-economic-environmental system. Water resources have dynamic interactions with related social, economic and environmental elements, as well as regulatory factors that are characterized by non-linear and multi-loop feedbacks. In this paper, a complex System Dynamic (SD) model is used to study the relationship among population growth, economic development, climate change, management strategies and water resources, and identify the best management strategy to adapt with the changing environment in the Tuwei river basin of Northwest China. Three management alternatives viz. business as usual, water supply management and water demand management are studied under different climate change scenarios. Results indicate that water shortage rate in Tuwei river basin may increase up to 80 % by the year 2030 if current management practices are continued or the supply based management strategy is adopted. On the other hand, water demand management can keep the water shortage rate within a tolerable limit and therefore can be considered as the sustainable strategy for water resources management to maintain the economic growth and ecological status of the Tuwei river basin.

Climate change and water resources management in Tuwei river basin of Northwest China

The objective of the paper is to assess the impacts of climate change, population growth and economic development on water demand of Yulin city located in Shaanxi Province of northwest China by using system dynamics approach. Total water consumption is divided into different sectors following the technical specification used for the analysis of water supply and demand balance in China. Water demand in each sector is modeled separately to compute the total water demand. System dynamics models for water demand forecasting are developed by considering the environmental (water quality, ecosystem preservation) and socio-economic (population growth, water consumption, policy and management) factors of regional water demand, and their nonlinear interactions with the physical elements of hydrological processes (natural runoff, groundwater recharge). The model is calibrated by using historical data and then applied for forecasting water demand in Yulin city under projected changes in climate, population, and economy. The study reveals that total water demand in Yulin city will increase from approximately 710million-m3 in 2010 to more than 1480million-m3 in 2030. Total water demand under A1B scenario which lies near the high end of the spectrum for future greenhouse gas emissions will be 2.51million-m3 more compared to B1 scenario. This is due to the projection of higher temperature by A1B scenario. It is concluded that Yulin city should adopt water demand management strategy to achieve sustainability in water resources.

He Rui-min

Papers

Water resources management strategy for adaptation to droughts in China

Catastrophe theory to assess water security and adaptation strategy in the context of environmental change

Climate change and water resources management in Tuwei river basin of Northwest China

Potential impact of climate change on future water demand in Yulin city, Northwest China

Impact of Climate Change on Water Security in China