《Water Resources Research》刊登“气候变化条件下美国未来用水量预测”

作者：Thomas C. Brown1, Romano Foti, Jorge A. Ramirez

刊物：Water Resources Research, 2013年，49卷，第3期，页码：1259–1276

关键词：需水量；用水量；气候变化；用水效率；用水户

摘要：基于美国地质调查局1960-2005年的用水数据，本文总结了过去的用水情况并预测了基于当今用水效率与主要用水户的未来用水情况。用水效率在许多行业都有所提升。在过去的45年，工业与电热行业单位产出的取水量稳步下降。另外，在大部分西部地区，人均生活与市政取水量及单位面积农业灌溉取水量最近开始减少。如果当前用水效率趋势能够持续，且用水驱动要素的演变趋势无意外变化，那么在不考虑气候变化的情况下，在未来50年美国预期的用水量相对2005年用水水平的波动不会超过3%，尽管预期将会有51%的人口增长。然而，如果考虑到未来气候变化的持续性，那么该预测的用水量将会增加。气候变化将主要导致农业与景观灌溉用水量的增加和发电行业用水量的减少，这主要是由于潜在蒸散发的增加和气温升高导致的制冷需求的增多。预期用水量的增加在研究的98个流域中很不相同，有些流域表现出减少的趋势而其他流域却表现出明显的增加趋势，而且对排放情景和气候变化非常敏感。同时也发现，当使用基于气温的方法计算潜在蒸散发量时，用水量的增加值将比基于物理机制的方法（考虑到能量、湿度和风速）要大很多。

Projected freshwater withdrawals in the United States under a changing climate

Authors : Thomas C. Brown1, Romano Foti, Jorge A. Ramirez

Journal: Water Resources Research, Volume 49, Issue 3, pages 1259–1276, March 2013

Keywords: water demand; water withdrawal; climate change; water use efficiency; water use drivers

Abstract：Relying on the U.S. Geological Survey water use data for the period 1960−2005, this paper summarizes past water use and then projects future water use based on the trends in water use efficiency and major drivers of water use. Water use efficiency has improved in most sectors. Over the past 45 years, withdrawals in industry and at thermoelectric plants have steadily dropped per unit of output. In addition, domestic and public withdrawals per capita, and irrigation withdrawals per unit area in most regions of the west, have recently begun to decrease. If these efficiency trends continue and trends in water use drivers proceed as expected, in the absence of additional climate change the desired withdrawals in the United States over the next 50 years are projected to stay within 3% of the 2005 level despite an expected 51% increase in population. However, including the effects of future climate change substantially increases this projection. The climate-based increase in the projected water use is attributable mainly to increases in agricultural and landscape irrigation in response to rising potential evapotranspiration, and to a much lesser extent to water use in electricity production in response to increased space cooling needs as temperatures rise. The increases in projected withdrawal vary greatly across the 98 basins examined, with some showing decreases and others showing very large increases, and are sensitive to the emission scenario and global climate model employed. The increases were also found to be larger if potential evapotranspiration is estimated using a temperature-based method as opposed to a physically based method accounting for energy, humidity, and wind speed.

原文链接：http://onlinelibrary.wiley.com/doi/10.1002/wrcr.20076/abstract