Modelling glacier and ice sheet response to climate change

模拟冰川和冰盖对气候变化的响应

• 批准号: 227436-2009
• 负责人: Marshall, Shawn
• 金额: $ 4.66万
• 依托单位: University of Calgary
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=594061
• 关键词: Modelling; glacier; ice; sheet; response

This research program aims to improve understanding of glacier and ice sheet response to climate change. My research group uses a combination of glaciological modelling and glacier-climate field studies to assess changes in glacier mass balance and to examine the role of glaciers as a dynamic component of Earth's climate system. Regionally, glacier and icefield retreat affects alpine ecology, tourism, hydroelectric power generation, and the supply of surface water for significant population bases and agricultural activities. We are developing glaciological models to simulate glacier and ice sheet evolution over decadal time scales. Field studies for the period 2009-2014 will focus on historical and future icefield changes and water resource implications in western Canada, building on our established research program on the Haig Glacier, Canadian Rockies. Beginning in spring 2009, we will expand these efforts to the Illecillewaet Glacier, Glacier National Park, B.C. The Illecillewaet is a headwaters region of the Columbia River, with a high percentage of glacier cover and a more maritime-influenced climate. Meteorological controls of snow accumulation and snow/ice melt may differ significantly from those in the Canadian Rockies. Globally, glacier and ice sheet retreat has accelerated the rate of sea level rise, with considerable uncertainty as to how much additional sea-level rise can be expected this century. Advances in coupled glacier-climate modelling are needed to address this. This includes a number of numerical modelling issues that we aim to confront: the inclusion of higher-order terms in the ice sheet stress balance, improvements to the numerical representation of glacier and ice sheet margins, and downscaling strategies for regional climate patterns in areas of complex topography. Climate fields need to be extrapolated from sparse observational records or interpolated from climate models (or reanalyses) to the scale of influence for glacier and ice sheet mass balance, order 1-10 km. Our field studies support the numerical modelling through examination of mass balance processes and high-elevation temperature and precipitation gradients, providing constraints on free parameters in regional- and global-scale glaciological modelling.

该研究计划旨在增进对冰川和冰盖对气候变化响应的了解。我的研究小组结合冰川学模型和冰川气候实地研究来评估冰川质量平衡的变化，并研究冰川作为地球气候系统动态组成部分的作用。从区域来看，冰川和冰原退缩影响高山生态、旅游业、水力发电以及重要人口基础和农业活动的地表水供应。我们正在开发冰川学模型来模拟十年时间尺度上的冰川和冰盖演化。 2009-2014 年期间的实地研究将重点关注加拿大西部历史和未来的冰原变化以及水资源影响，以我们对加拿大落基山脉黑格冰川的既定研究计划为基础。从 2009 年春季开始，我们将把这些工作扩展到不列颠哥伦比亚省冰川国家公园的伊勒西勒瓦特冰川 (Illecillewaet Glacier)。伊勒西勒瓦特 (Illecillewaet) 是哥伦比亚河的源头地区，冰川覆盖率很高，气候受海洋影响较大。对积雪和雪/冰融化的气象控制可能与加拿大落基山脉的情况有很大不同。在全球范围内，冰川和冰盖的退缩加速了海平面上升的速度，本世纪海平面预计还会上升多少存在很大的不确定性。需要在冰川-气候耦合建模方面取得进展来解决这个问题。这包括我们要面对的许多数值模拟问题：在冰盖应力平衡中包含高阶项，改进冰川和冰盖边缘的数值表示，以及区域气候模式的降尺度策略复杂的地形。气候场需要从稀疏的观测记录中推断或从气候模型（或重新分析）中插值到冰川和冰盖质量平衡的影响范围（1-10公里）。我们的实地研究通过检查质量平衡过程以及高海拔温度和降水梯度来支持数值建模，为区域和全球尺度冰川建模中的自由参数提供约束。