Measurement and Modelling of the Variability of Lake Ice Growth and Decay in Alaska

阿拉斯加湖冰生长和衰退变化的测量和建模

• 批准号: 0117645
• 负责人: Martin Jeffries
• 金额: $ 25.07万
• 依托单位: University of Alaska Fairbanks Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-01 至 2005-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0117645&HistoricalAwards=false
• 关键词: Measurement; Modelling; Variability; Lake; Ice

Abstract JefferiesOPP-01-17645Since 1846, the duration of the ice cover on Northern Hemisphere lakes and rivers has decreased by almost 20 days. A three week reduction in ice duration on lakes in Ontario, Canada since 1969 has caused major limnological and ecological changes. Since the late 1980s/early 1990s, there has been significant environmental change in the ocean, atmosphere, and cryosphere of the Arctic. The recently released third assessment of the Intergovernmental Panel on Climate Change, 2001 indicates that the sensitive and already changing northern high latitude cryosphere faces further change as winter temperatures and precipitation increase at high northern latitudes. Lake ice in Alaska may be responding to late twentieth century environmental changes and may respond to further climatic perturbations. However, the observational record is neither sufficiently long and continuous, nor covers the appropriate period to allow for a proper assessment of past lake ice variability and the likely magnitude of future change. The objective of this study is to use numerical modeling to simulate the variability of lake ice growth and decay at the present time and during the period of meteorological record in the different climate zones of Alaska, and to understand the factors responsible for that variability in order to predict the response of the ice to future climate change. Lake ice growth and decay variables include freezing, ice thickness, modes of thickening [congelation ice, snow ice], and break-up. This is a larger and more comprehensive set of variables than has been considered previously and they integrate the effects of both temperature and precipitation variability. Successful completion of this study will yield well-validated lake ice growth and decay model that will enable us to identify the key factors responsible for the variability of lake ice growth and decay. This will fill a major gap in the knowledge and understanding of the response of the Arctic and sub-Arctic cryosphere to past climate variability and change, and the prediction of future response. This will benefit physical, chemical, and biological limnologists, and ecological andwater resource managers. Teacher and student participation will give them a better appreciation for teaching and learning in the local context, an understanding of the scientific process, and interesting and relevant examples of the impact of climate variability and change on Alaska physical processes and interactions.

自1846年以来，北方湖泊和河流的冰盖持续时间减少了近20天。自1969年以来，加拿大安大略湖的冰持续时间减少了三周，造成了重大的湖沼学和生态学变化。自20世纪80年代末/90年代初以来，北极的海洋、大气和冰冻圈发生了重大的环境变化。最近发表的政府间气候变化问题小组2001年第三次评估报告指出，随着北方高纬度地区冬季气温和降水量的增加，北方高纬度地区的敏感和已经在变化的冰冻圈面临进一步的变化。 阿拉斯加的湖冰可能是对20世纪后期环境变化的反应，也可能是对进一步的气候扰动的反应。然而，观测记录既不足够长和连续，也没有涵盖适当的时期，以便对过去的湖冰变化和未来变化的可能幅度进行适当的评估。本研究的目的是使用数值模拟模拟湖冰的增长和衰减的变化，在目前的时间和在阿拉斯加不同的气候区的气象记录期间，并了解负责该变化的因素，以预测冰对未来气候变化的响应。湖冰的增长和衰减变量包括冻结，冰的厚度，增厚的模式[冰，雪冰]，和破碎。 这是一个更大和更全面的变量比以前已经考虑，他们整合了温度和降水变化的影响。 这项研究的成功完成将产生经过充分验证的湖冰增长和衰减模型，使我们能够确定负责湖冰增长和衰减的变化的关键因素。这将填补在了解和理解北极和亚北极冰冻圈对过去气候变率和变化的反应以及预测未来反应方面的一个重大空白。这将使物理、化学和生物湖沼学家以及生态和水资源管理人员受益。教师和学生的参与将使他们更好地了解当地的教学和学习，了解科学过程，以及气候变异性和变化对阿拉斯加物理过程和相互作用的影响的有趣和相关的例子。