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12:44
Watershed Planning within a Quantitative Scenario Analysis Framework
Published on: July 24, 2016
Global hydrological cycles and world water resources
1Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan. taikan@iis.u-tokyo.ac.jp
Science (New York, N.Y.)
|August 26, 2006
Summary
Focusing on water flow, not just storage, is key for water resource assessments. Climate change may increase renewable freshwater resources but also exacerbate water stress due to uneven distribution and extreme events.
Area of Science:
- Hydrology
- Climate Science
- Environmental Science
Background:
- Water is a renewable resource, recharged through natural circulation.
- Water resource assessments traditionally focus on water stocks (reservoirs), but water flow is critical.
- Global water withdrawals are currently below the climate system's limit for renewable freshwater resources (RFWR).
Purpose of the Study:
- To emphasize the importance of water flow in water resource assessments.
- To analyze the impact of climate change on renewable freshwater resources and water stress.
- To highlight the need for reducing current vulnerability to anticipated changes.
Main Methods:
- Analysis of water circulation and renewable freshwater resources (RFWR) in relation to climate systems.
- Assessment of global water withdrawals against established limits.
- Evaluation of climate change impacts on water cycle acceleration and distribution patterns.
Main Results:
- The climate system dictates the maximum rate of RFWR circulation.
- Over two billion people currently face high water stress due to uneven RFWR distribution.
- Climate change is projected to increase RFWR but may also worsen water stress through altered seasonal patterns and extreme events.
Conclusions:
- Water flow, not just storage, should be the primary focus in water resource assessments.
- While climate change may increase overall RFWR, its effects on distribution and extreme events pose significant risks.
- Reducing current vulnerability is essential for adapting to future water resource challenges.
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