Water scarcity

About: Water scarcity is a research topic. Over the lifetime, 11579 publications have been published within this topic receiving 228756 citations. The topic is also known as: water shortage.

Water scarcity hotspots travel downstream due to human interventions in the 20th and 21st century

Abstract: Water scarcity is rapidly increasing in many regions. In a novel, multi-model assessment, we examine how human interventions (HI: land use and land cover change, man-made reservoirs and human water use) affected monthly river water availability and water scarcity over the period 1971–2010. Here we show that HI drastically change the critical dimensions of water scarcity, aggravating water scarcity for 8.8% (7.4–16.5%) of the global population but alleviating it for another 8.3% (6.4–15.8%). Positive impacts of HI mostly occur upstream, whereas HI aggravate water scarcity downstream; HI cause water scarcity to travel downstream. Attribution of water scarcity changes to HI components is complex and varies among the hydrological models. Seasonal variation in impacts and dominant HI components is also substantial. A thorough consideration of the spatially and temporally varying interactions among HI components and of uncertainties is therefore crucial for the success of water scarcity adaptation by HI.

Water allocation mechanisms : principles and examples

Abstract: What does it mean to treat water as an economic good? What does it mean to allocate appropriately? From the earliest times, water resources have been allocated on the basis of social criteria - maintaining the community by ensuring that water is available for human consumption, for sanitation, and for food production. Societies have invested capital in infrastructure to maintain this allocation. Yet social change, including changes in (and more understanding of) how goods are distributed, has produced new issues in water allocation. Population growth has made water scarcity a major problem in many countries and water pollution, while by no means a recent problem, is more widespread than ever before. Traditionally the state has played a dominant role in managing water resources, but inefficient use of water, poor cost recovery for operating and maintenance expenses, the mounting cost of developing new water sources, and problems with the quality of service in agency-managed systems has led to a search for alternatives that make water allocation and management more efficient. Dinar, Rosegrant, and Meinzen-Dick address some of the basic principles of treating water as an economic good and of allocating it among sectors. After outlining the economic principles behind allocating scarce water resources, they review the actual means of various mechanisms used for allocating water, including marginal cost pricing, social planning, user-based allocation, and water markets. Giving examples from experience in several countries, they weigh the pros and cons of different approaches to water allocation, showing that no single approach is suitable for all situations. Clearly the state must play an important regulatory role, for example, but how effectively it does so depends on the relative political influence of various stakeholders and segments of society. User-based allocation is generally more flexible than state allocation, but collective action is not equally effective everywhere; it is most likely to emerge where there is strong demand for water and a history of cooperation. The outcome of market allocation depends on the economic value of water for various uses, but moving toward tradable property rights in water may ease the process of intersectoral reallocation by compensating the losers and creating incentives for efficient water use in all sectors. This paper - a joint product of the Sector Policy and Water Resources Division, Agriculture and Natural Resources Department, and the International Food Policy Research Institute - is part of a larger effort implement the 1993 World Bank`s Water Resources Management Policy.