Impacts of climatic and environmental changes to Hydrologic Extremes and Adaptation strategies

气候和环境变化对水文极端事件的影响和适应策略

基本信息

批准号：
RGPIN-2017-04724
负责人：
Gan, ThianYew
金额：
$ 2.04万
依托单位：
University of Alberta
依托单位国家：
加拿大
项目类别：
Discovery Grants Program - Individual
财政年份：
2020
资助国家：
加拿大
起止时间：
2020-01-01 至 2021-12-31
项目状态：
已结题

来源：
https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=711173
关键词：
Impacts climatic environmental changes Hydrologic

项目摘要

In recent years, severe storms have been occurring more frequently and in greater intensity across the world because of global warming, which could cause existing Intensity-Duration-Frequency (IDF) curves for engineering design obsolete, e.g., thousands of basements of Edmonton were flooded in 1995, 2004 and 2012, by storms which based on existing IDF curves for the City are supposed to occur once every 100 years. In June 2013, the southern Alberta flood incurred a damage of $6 billion. On the other hand, the drought of 2001/02 had caused loss of multibillion dollar revenues from agriculture. Another impact of warming will be the water availability of most Canadian watersheds dominated by snowpack because a warmer climate means an earlier onset of spring snowmelt and enhanced evaporation loss in the summer, resulting in decreased summer streamflow most needed for summer growing seasons. This research will advance our understanding of climate change and our ability to predict the impact of warming to changes in the climate and water resources of Canada. Specifically, for flood hazards: (1) To conduct in-depth analysis of extreme precipitation events to assess their spatial variability and projected changes in selected regions across Canada, given that different climatic regimes can respond differently to climate change impact; (2) To test the applicability of commonly used extreme precipitation indices over these regions, and to develop new extreme precipitation indices; (3) To estimate return periods of future extreme storms based on regional IDF curves estimated from simulations of a regional climate model coupled to a land surface model to account for the land-atmosphere feedback and subjected to the latest RCP (Representative Concentration Pathway) climate scenarios of IPCC (2013); (4) To conduct a drought analysis using observed climate data and versatile drought index algorithms for summer over coherent regions of Canada; (5) To understand the impact of climate change to future droughts, selected drought indices will be simulated from RCP climate scenarios statistically or dynamically downscaled for 2050s and 2080s. To simulate the possible combined impact of climate change and El Nio events historically associated with below normal precipitation in western Canada, a bootstrap resampling approach will be used to generate 30-year period datasets adjusted for the combined impact of climate change based on RCP climate scenarios and ENSO using the quantile-quantile mapping method for 2050s and 2080s. The potential impact of climate change to the future water sources of Canadian watersheds dominated by spring snowmelt will be simulated by a hydrologic model forced with downscaled RCP climate scenarios of IPCC (2013). Lastly, adaptation strategies, early warning systems and capacity building measures will be examined to promote preparedness of Canada against climate change impact.

近年来，由于全球变暖，全球范围内的严重风暴发生频率更高、强度更大，这可能导致现有的工程设计强度-持续时间-频率（IDF）曲线过时，例如埃德蒙顿的数千个地下室被洪水淹没1995 年、2004 年和 2012 年，根据该市现有的 IDF 曲线，预计每 100 年发生一次的风暴。 2013年6月，阿尔伯塔省南部洪水造成了60亿美元的损失。另一方面，2001/2002年的干旱造成农业收入损失数十亿美元。变暖的另一个影响是加拿大大多数流域的水供应以积雪为主，因为气候变暖意味着春季融雪提前开始，夏季蒸发损失增加，导致夏季生长季节最需要的夏季水流减少。这项研究将增进我们对气候变化的理解以及我们预测变暖对加拿大气候和水资源变化影响的能力。具体来说，针对洪水灾害： (1) 对极端降水事件进行深入分析，以评估其空间变异性以及加拿大选定地区的预计变化，因为不同的气候状况对气候变化影响的反应可能不同；（2）测试常用极端降水指数在这些地区的适用性，并制定新的极端降水指数； (3) 根据区域 IDF 曲线来估计未来极端风暴的重现期，该曲线是通过区域气候模型与地表模型耦合的模拟来估计的，以考虑陆地-大气反馈并受到最新的 RCP（代表性浓度路径）气候的影响IPCC 情景（2013 年）； (4) 利用观测到的气候数据和通用干旱指数算法对加拿大相关地区的夏季进行干旱分析； (5) 为了了解气候变化对未来干旱的影响，将根据统计或动态缩小的 2050 年代和 2080 年代 RCP 气候情景模拟选定的干旱指数。为了模拟历史上与加拿大西部降水量低于正常水平有关的气候变化和厄尔尼诺事件可能产生的综合影响，将使用引导重采样方法生成 30 年周期数据集，并根据 RCP 气候情景调整气候变化的综合影响ENSO 使用 2050 年代和 2080 年代的分位数-分位数映射方法。气候变化对以春季融雪为主的加拿大流域未来水源的潜在影响将通过水文模型进行模拟，该模型采用IPCC（2013）缩小规模的RCP气候情景。最后，将审查适应战略、预警系统和能力建设措施，以促进加拿大应对气候变化影响的准备工作。