How does climate change contribute to lake warming and alterations in water quality?

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The impact of climate change on water quality has been identified as one of the most important challenges facing humankind. In particular, it is vital to understand the mechanisms involved in lake warming and its consequences on water quality. Lake warming increases the risk of nuisance algal blooms, which can negatively affect drinking water, domestic household water use, food production, and recreational activities. Lake ice phenology (defined as the timing of ice breakup and freeze) is a sensitive indicator of climate warming and has been recorded for centuries around the world because of its importance to transportation, winter recreation, and religion. My long-term research objectives are to predict the future impacts of global environmental change on lakes. My short-term objectives are to understand the impacts of climate change on the patterns, trends, and drivers of lake ice cover, water temperatures, and water quality. For example, what are the drivers of no-freeze events and are they coherent spatio-temporally?; Is earlier ice break-up contributing to warmer water temperatures?; How do climate, landscape characteristics, and lake morphology interact to inform spatial patterns in water quality worldwide?; and Which lakes are most vulnerable to degraded water quality? We will capitalize on long-term climatic and ecological time series collected from hundreds of lakes around the Northern Hemisphere to address our research questions and quantify the impacts of climate change on lake ice phenology, lake warming, and water quality. We are developing and updating three databases: 1) Global Lake and River Ice Phenology database, which dates back to 853 AD and represents over 520 time-series from lakes around the Northern Hemisphere; 2) Global Lake Temperature Collaboration database summarizing lake surface water temperatures, climate, and geomorphological characteristics between 1985 and 2009 for 291 lakes located around the world; and 3) Global Water Quality Database summarizing chlorophyll, water clarity, and nutrient concentrations from 26,000 lakes found in 91 countries. We will use cutting-edge statistical analysis to identify whether earlier ice break-up and reduced ice cover will lead to warmer water temperatures and degraded water quality. Over the duration of the proposal, I will train 2 Post-doctoral Researchers, 2 PhD students, 3 MSc students, and 5 BSc students. All HQP will gain knowledge in advanced data management and statistical skills while quantifying complex relationships between weather, climate, and lake morphology, to understand the impacts of climate change on lake warming and water quality of lakes around the world. Ultimately, our ability to identify which lakes are vulnerable to warming and degraded water quality in response to climate change will permit the development of vulnerability assessments and focused adaptation plans to mitigate climate change impacts on fresh water quality.