近年來，全球暖化影響未來面臨海水上升之危機已被高度關注，這是一個長期的議題。暖化帶來的溫度上升之結果導致海水溫度增加，透過熱擴散作用，使得冰山、冰帽及冰層融化。由聯合國政府間氣候變遷小組第二工作組第四評估報告指出，未來氣候變遷將會有諸多影響，尤其，沿岸地區更加嚴重。對沿岸地區的影響包含：沿岸侵蝕加劇、改變地面水及地下水水質。
本研究運用時間獨立之有限差分法模擬沿海含水層海水入侵之結果，並以二維尺度來呈現。本模式探討沿海地區海水面上升對不同水文地質條件海水入侵影響之情形。本模式將與前人研究以傳統的Henry problem結果做驗證。Henry problem呈現一受水層海水入侵過程中鹽水的擴散與淡水之間作用力平衡之穩態解。淡水定流量流入假想的內陸邊界並且在假想的沿海邊界流出；而海水由沿海邊界擴散且與流出的淡水混合。Henry problem為理想的海水入侵模式，本模式將依據Henry problem以模擬因海水面上升導致海水入侵之範圍。因此，本研究將做為氣候變遷所導致之海水面上升海水入侵範圍的預測。

Sea level rise has currently been suggested to be due significantly to global warming, which increases sea level over the coming century and longer periods. Increasing temperatures result in sea level rise both by the thermal expansion of water and by the addition of water to the oceans from the melting of mountain glaciers, ice caps, and ice sheets. Based on the IPCC (Intergovernmental Panel on Climate Change), FAR (Fourth Assessment Report), and WG (Working Group) II reports, it is noted that current and future climate changes and sea level rise would be expected to have a number of impacts, particularly on coastal systems. Such impacts may include increased coastal erosion, as well as changes in surface water quality and groundwater characteristics.
This study presents a two-dimensional time-independent finite difference model to simulate the intrusion of seawater in coastal aquifers. This model considers the effect of sea level rise with different hydrogeological conditions on coastal areas. The numerical technique is validated by the result of the traditional Henry problem. Henry’s problem addresses the steady-state solution of a diffused saltwater wedge within a confined aquifer balanced against a flowing freshwater field. Fresh water enters the confined aquifer at a constant rate from a hypothetical inland boundary and discharges into a hypothetical coastal boundary. Salt water from the coastal boundary diffuses and mixes with the discharging fresh water. Idealized saltwater intrusion, known as the Henry problem, was extended to simulate seawater intrusion on coastal areas accounting for effects of sea level rise. Therefore, the impacts of sea level rise caused by climate changes on seawater intrusion will be investigated in this study.

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