How do extreme climatic events impact lake ice phenology and ecosystem structure?

气候变化对水质的影响已被确定为人类面临的最重要挑战之一。然而，极端气候事件对湖泊生态系统的影响相对而言尚未得到探讨，部分原因是缺乏长期数据。湖冰物候是一个敏感的气候指标，由于其对交通、冬季娱乐和宗教的重要性，世界各地已经记录了几个世纪。 我们将利用从北方数百个湖泊收集的长期气候和生态时间序列，量化极端事件及其对湖冰物候、湖泊变暖、水质和生产力的影响。总体而言，我的研究目标是预测湖泊对多种环境压力的反应，包括在广泛的空间和时间尺度上的气候变化。在这里，更具体地说，我的研究旨在回答关于极端气候事件对湖泊的作用的三个问题：1）我们如何量化生态学中的极端事件？2)极端气候事件如何影响湖冰的损失以及冰破裂和冻结的时间？3）极端气候事件如何影响湖泊的物理、化学和生物学？我们将联系原始数据提供商，更新来自北方半球的520个湖冰物候时间序列。此外，我们将使用开放访问的全球数据库获取每个湖泊的地貌，当地天气和大规模气候驱动因素。这些数据集将合并成一个开放式数据库，以比较极端气候事件的统计定义，并确定在冰物候记录中显示极端温暖事件所需的当地天气和大规模气候条件。接下来，我们将量化极端气候事件如何影响520个湖泊中的生态系统结构，我们可以获得生态系统水平的数据。我们将量化物理（例如，水温、分层、水透明度），化学（例如，氧气，营养物），和生物（例如，生产力、浮游动物生物量、鱼类产量）对极端气候事件的反应。HQP将使用和比较尖端的创新统计方法来量化天气，气候，湖泊形态和生态系统结构之间的复杂关系，以了解极端气候事件对北方半球湖泊的影响。最终，我们将确定哪些湖泊在应对极端气候事件时容易受到变暖和水质退化的影响。这些湖泊将需要脆弱性评估和有重点的适应计划，以减轻气候变化对世界各地湖泊水质的影响。

The impact of climate change on water quality has been identified as one of the most important challenges facing humankind. However, the influence of extreme climatic events on lake ecosystems has been relatively unexplored, in part due to a paucity of long-term data. Lake ice phenology is a sensitive indicator of climate and has been recorded for centuries around the world because of its importance to transportation, winter recreation, and religion. We will capitalize on long-term climatic and ecological time series collected from hundreds of lakes around the Northern Hemisphere to quantify extreme events and their impacts on lake ice phenology, lake warming, water quality, and productivity. Overall, my research objectives are to predict the responses of lakes to multiple environmental stressors, including climate change at broad spatial and temporal scales. Here, more specifically, my research aims to answer three questions on the role of extreme climate events on lakes: 1) How do we quantify an extreme event in ecology?; 2) How do extreme climatic events influence the loss of lake ice and the timing of ice breakup and freeze?; and 3) How do extreme climatic events influence lake physics, chemistry, and biology? We will contact original data providers to update 520 lake ice phenology time-series from around the Northern Hemisphere. Moreover, we will acquire geomorphology, local weather, and large-scale climatic drivers for each lake using open-access global databases. These datasets will be merged into an open-access database to compare statistical definitions of extreme climatic events and to identify the local weather and large-scale climatic conditions required for an extreme warm event to be manifested in the ice phenology record. Next, we will quantify how extreme climatic events influence ecosystem structure in as many of the 520 lakes for which we can acquire ecosystem level data. We will quantify the physical (e.g., water temperature, stratification, water clarity), chemical (e.g., oxygen, nutrients), and biological (e.g., productivity, zooplankton biomass, fish production) responses to extreme climatic events. HQP will use and compare cutting-edge innovative statistical approaches to quantify complex relationships between weather, climate, lake morphology, and ecosystem structure to understand the impacts of extreme climatic events on lakes around the Northern Hemisphere. Ultimately, we will identify which lakes are vulnerable to warming and degraded water quality in response to extreme climatic events. These lakes will require vulnerability assessments and focused adaptation plans to mitigate climate change impacts on water quality in lakes around the world.