Ice cover in lake-climate interactions at high latitudes

湖泊是气候变率和变化的敏感指标。它们还在局地和区域尺度上的能量和水平衡中发挥重要作用，影响气候和天气（例如，对周围陆地地区的气温和冬季湖泊效应降雪的调节作用）。在安大略省和美国的五大湖地区，湖效应雪是一个有充分记录的现象。然而，人们对大湖泊的作用或高纬度地区湖泊丰富地区的小水体对气候和天气的综合影响知之甚少。此外，关于不同大小的湖泊对最近记录和预测的北极气候变暖的反应，还有很多有待了解。在这些寒冷的环境中，对气候条件敏感并影响湖泊-大气相互作用的关键变量之一是冰盖。它的存在/不存在和厚度对与上覆大气的能量/热量交换有影响。然而，这些交换的规模很少被记录和量化。利用最先进的遥感和数值模拟，我的研究计划将在以下方面取得实质性进展：(i)记录和阐明北极湖泊冰盖对气候的当代响应，并与北极系统的其他组成部分建立联系；（ii）确定在21世纪末之前，整个北极的湖冰覆盖条件可预期发生哪些变化；（iii）确定和量化湖冰覆盖对北极天气和气候的作用。随着气候变暖，冰情的变化将对能源、水和生物地球化学循环产生重要的反馈效应，并对水生系统的生物生产力产生重大影响。这种变化将对北极社区的食物供应/质量（即鱼类）产生重大影响。海冰覆盖季节和冰层厚度的减少也会降低传统冰上狩猎路线的可靠性和冰上旅行的安全性，从而造成获取食物的问题。因此，我的研究项目将通过在变暖的北极气候中产生关于湖泊冰情状况的新数据和信息，为社会做出重要贡献。

Lakes are sensitive indicators of climate variability and change. They also play an important role in the energy and water balance at local and regional scales, influencing climate and weather (moderating effect on air temperature of surrounding land areas and lake-effect snowfall in winter, for example). Lake-effect snow is a well-documented phenomenon for the Great Lakes region of Ontario and U.S. However, little is known about the role of large lakes or the combined effect of smaller water bodies in lake-rich areas found at high latitudes on climate and weather. Also, much remains to be learned about the response of lakes of various sizes to recently documented and projected Arctic climate warming. One of the key variables that is sensitive to climate conditions and that influences lake-atmosphere interactions in these cold environments is ice cover. Its presence/absence and thickness have an impact on energy/heat exchanges with the overlying atmosphere. Yet, the magnitude of these exchanges is poorly documented and quantified. Using state-of-the-art remote sensing and numerical modeling my research program will make substantial progress toward: (i) documenting and elucidating the contemporary response of Arctic lake ice cover to climate, and establish linkages with other components of the Arctic system; (ii) determining what changes can be expected in lake ice cover conditions across the Arctic until the end of the 21st century; and (iii) determining and quantifying the role of lake ice cover on Arctic weather and climate. Changes in ice conditions with climate warming are anticipated to have an important feedback effect on energy, water and biogeochemical cycling, and significant impacts on the biological productivity of aquatic systems. Such changes will have a significant influence on food availability/quality (i.e. fish) for Arctic communities. A reduction in ice cover season and ice thickness will also create problems of accessibility to food by reducing the reliability of traditional hunting ice-based routes and safety of ice-based travel. My research program will therefore make an important societal contribution by generating new data and information on the state of lake ice conditions in a warming Arctic climate.