Impact of climate variability on groundwater in coastal cities

气候变化对沿海城市地下水的影响

• 批准号: 8451-2011
• 负责人: Howard, Kenneth
• 金额: $ 1.6万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=568590
• 关键词: Impact; climate; variability; groundwater; coastal

Population growth, sprawling cities and the effects of climate change seriously threaten the sustainability of global water supplies. Pro-active resource management decisions are required, but such efforts will prove meaningless unless reliable predictions can be made of the impact that rapidly changing conditions will impart upon the water cycle and water resources. The threat is especially severe in coastal cities which host close to 50% of the global population. In many coastal cities, the management and protection of groundwater is already challenged by accelerating demand for the resource in the face of depleted natural recharge, pollution from urban-sourced contaminants and (for sea coasts) the intrusion of seawater. Climate variability and changing sea levels will intensify such resource management problems by altering the recharge regime and stimulating the movement of both contaminants and the fresh-saline water interface. Applying urban water system models that have been calibrated with field data to simulate the complex recharge conditions and "karstic" groundwater flow behaviour that typify urban aquifer systems, we will address fundamental research questions regarding the transient response of coastal aquifers to conditions imposed by climate variability: e.g. 1) How will climate change affect the nature and seasonality of urban recharge? 2) How will groundwater levels beneath coastal cities respond to changing sea/lake levels, and to what extent will rising sea levels promote the intrusion of seawater? 3) Will a decline in sea/lake level accelerate the release of contaminants stored in urban aquifers to receiving water bodies? 4) Over what time frame will system changes occur? 5) What are the options for ameliorative action and when should they be implemented? The research is novel in that very little is known about the potential impacts of climate change on urban aquifers, particularly those in coastal areas where sea levels are expected to rise and, in some cases, fall at rates that are unprecedented in modern times. Over 5 years, the work will involve a minimum of 12 HQP (2 PhD students, 5 MSc students and 5 final year undergraduates).

人口增长、城市扩张和气候变化的影响严重威胁到全球水资源供应的可持续性。必须作出积极的资源管理决定，但除非能够可靠地预测迅速变化的条件将对水循环和水资源造成的影响，否则这种努力将被证明是毫无意义的。这一威胁在沿海城市尤为严重，这些城市拥有全球近50%的人口。在许多沿海城市，面对自然补给枯竭、来自城市来源的污染物的污染以及(对于沿海)海水入侵，对地下水的管理和保护已经面临着对资源需求的加速。气候多变性和海平面变化将改变补给制度并刺激污染物和淡水-咸水界面的移动，从而加剧这种资源管理问题。 应用已用现场数据校准的城市水系统模型来模拟典型的城市含水层系统的复杂补给条件和“岩溶”地下水流动行为，我们将解决有关沿海含水层对气候变化强加条件的瞬变响应的基本研究问题：例如：1)气候变化将如何影响城市补给的性质和季节性？2)沿海城市地下水位将如何应对海平面/湖泊水位的变化，海平面上升将在多大程度上促进海水的入侵？3)海平面/湖泊平面的下降是否会加速储存在城市含水层中的污染物向接收水体的释放？4)系统将在多长时间内发生变化？5)改善行动的选择是什么？它们应该在什么时候实施？这项研究是新颖的，因为人们对气候变化对城市含水层的潜在影响知之甚少，特别是在沿海地区，那里的海平面预计会上升，在某些情况下，下降的速度在现代是前所未有的。在5年的时间里，这项工作将涉及至少12名HQP(2名博士生，5名硕士学生和5名本科生)。