| 植被对干旱趋势的影响 |
| |
| 引用本文： | 刘永强.植被对干旱趋势的影响[J].大气科学,2016,40(1):142-156. |
| |
| 作者姓名： | 刘永强 |
| |
| 作者单位： | Center for Forest Disturbance Science, USDA Forest Service, 320 Green St., Athens, Georgia 30602, USA |
| |
| 基金项目： | 美国自然科学基金会、农业部和能源部联合项目:地球系统模式预报年代际区域气候 (NIFA-2013-35100-20516) |
| |
| 摘 要： | 历史干旱事件的观测和数值研究表明,植被可通过地—气水分、能量和其他通量交换影响和反馈干旱.本研究旨在了解气候变化情形下植被对干旱趋势的影响和机制.应用美国大陆七个动力气候降尺度区域气候变化情景,计算和分析了现在和未来的干旱指数、空间分布和季节变化.通过比较同一气候区两种植被类型区域干旱强度和频率理解植被的影响.集成分析结果表明,未来美国干旱很可能增加,其中大平原中部所有季节都很显著,而东南和西南地区夏秋更为显著.植被对干旱趋势的影响和气候区有关.在温暖和潮湿/干燥气候区,林地(草地)未来干旱强度和频率的增幅大于对应的农田(荒漠)区域,因此植被可以放大未来干旱的风险.相反,在寒冷和潮湿气候区,林地(草地)区域未来干旱强度和频率增幅较小,表明植被放大未来干旱的作用可能只在某些气候情形下出现.这种植被对未来干旱影响的复杂性和对气候区的依赖性对气候模式提供可靠的干旱模拟和预测及森林管理部门制定适应和减缓气候变化的策略提出了新的挑战.
|
| 关 键 词： | 植被 干旱 气候变化 干旱指数 美国气候区 |
| 收稿时间： | 3/8/2015 12:00:00 AM |
Impacts of Vegetation on Drought Trends |
| |
| LIU Yongqiang.Impacts of Vegetation on Drought Trends[J].Chinese Journal of Atmospheric Sciences,2016,40(1):142-156. |
| |
| Authors: | LIU Yongqiang |
| |
| Institution: | Center for Forest Disturbance Science, USDA Forest Service, 320 Green St., Athens, Georgia 30602, USA |
| |
| Abstract: | Vegetation conditions interact with and feed back to atmospheric anomalies such as droughts through water, energy and other exchanges on the land surface. Various mechanisms have been proposed to understand the related physical processes based on observational and numerical analyses of historical droughts. This study aims to understand the complex impacts and mechanisms of vegetation on future droughts under changing climate. Future trends in droughts were projected by comparing a drought index for present and future periods using seven dynamically downscaled regional climate change scenarios for the continental United States. The impacts of vegetation were examined by comparing changes in drought intensity and frequency between two types of land cover in each of six climate regimes. The ensemble results indicate that future droughts would increase in both intensity and frequency, mainly in the central Great Plains during all seasons, and in the Southeast and Southwest U.S. during warm seasons. The roles of vegetation depend on climate regime. Future droughts would increase more significantly on forest lands (grasslands) than the corresponding farmlands (drylands) in warm and moist/dry climate regimes. Vegetation, therefore, can amplify future droughts. In contrast, they would be less significant in cold and moist regimes, suggesting that the capacity of vegetation in amplifying future droughts would exist only in certain climate circumstances. The complex impacts and regional dependence raise new challenges for climate models to provide reliable drought simulation and projection, and for forest management to develop adaptation and mitigation strategies for climate change. |
| |
| Keywords: | Vegetation Drought Climate change Drought index U S climate regime |
| 本文献已被 CNKI 万方数据 等数据库收录！ |
| 点击此处可从《大气科学》浏览原始摘要信息 |
| 点击此处可从《大气科学》下载免费的PDF全文 |
|
