ABSTRACT

Inland lakes are socially and ecologically important components of many regional landscapes. Exploring lake responses to plausible future climate scenarios can provide important information needed to inform stakeholders of likely effects of hydrologic changes on these waterbodies in coming decades. To assess potential climate effects on lake hydrology, we combined a previously published spatially explicit, processed-based hydrologic modeling framework implemented over the lake-rich landscape of the Northern Highlands Lake District within the United States with an ensemble of climate change scenarios for the 2050s (2041–2070) and 2080s (2071–2100). Model results quantify the effects of climate change on water budgets and lake stage elevations for 3692 lakes and highlight the importance of landscape and hydrologic setting for the response of specific lake types to climate change. All future climate projections resulted in loss of ice cover and snowpack as well as increased evaporation, but variability in climate projections (warmer conditions, wet winters combined with wet or dry summers) interacted with lake characteristics and landscape position to produce variable lake hydrologic changes. Water levels for drainage lakes (lakes with substantial surface water inflows and outflows) showed nearly no change, whereas minimum water levels for seepage lakes (minimal surface water fluxes) decreased by an average of up to 2.64 m by the end of the 21st century. Our physically based modeling approach is parsimonious and computationally efficient and can be applied to other lake-rich regions to investigate interregional variability in lake hydrologic response to future climate scenarios.

摘要

内陆湖泊是许多区域景观的社会和生态重要组成部分。探索湖泊对可能的未来气候情景的响应可以提供重要的信息，让利益相关者了解未来几十年水文变化对这些水体的可能影响。为了评估气候对湖泊水文的潜在影响，我们将先前发布的空间明确的、基于处理的水文建模框架与 2050 年代气候变化情景集合相结合，该框架在美国北部高地湖区湖泊丰富的景观上实施（2041-2070）和 2080 年代（2071-2100）。模型结果量化了气候变化对 3692 个湖泊的水收支和湖位海拔的影响，并强调了景观和水文环境对于特定湖泊类型对气候变化的响应的重要性。所有未来的气候预测都导致冰盖和积雪的消失以及蒸发量的增加，但气候预测的变异性（更温暖的条件、潮湿的冬季与潮湿或干燥的夏季相结合）与湖泊特征和景观位置相互作用，从而产生可变的湖泊水文变化。到 21 世纪末，排水湖（地表水大量流入和流出的湖泊）的水位几乎没有变化，而渗流湖（地表水通量最小）的最低水位平均下降了 2.64 m。