While access to clean water is a pressing global health and security issue, and while fresh water protection is a key focus of international for both for climate change and biodiversity, those in Ontario who think that water, climate, and biodiversity concerns are far away would be misguided. With much research is generally available, four recent efforts and reports offer important insight into temperature and the quality of fresh water.
- A 2017 NASA report that summarizes 25 years of data on 235 large lakes on 6 continents. These lakes, including Lake Superior, are on average warming .34 degrees Celsius per decade. Impacts include decreasing oxygen and increased algal blooms, affecting aquatic life and potentially drinking water;
- An August 2018 report from Canada’s world-leading Experimental Lakes Area on temperature and the quality of fresh water, a summary of which can be seen at https://www.iisd.org/ela/blog/commentary/temperature-quality-fresh-water/. In addition to re-iterating issues relating to oxygen and algal blooms, this study comments on lake stratification, turn-over, and diminishing ice-cover, with large implications for fish breeding and growth;
- The re-emergence of extensive algal blossoms in Lake Erie as an issue requiring bi-national action, leading to the 2018 Canada-Ontario Lake Erie Action Plan to reduce phosphorus levels. Part of this issue is related to reducing phosphorus inputs themselves – thought to have been dealt with in the 1960s by banning phosphates in laundry detergent – but part of it deals with both warming water temperature itself and greater rainfall washing numerous nutrients that contribute to algae off the land; and,
- If Lake Erie is not warning enough, the appearance this month of perhaps the largest algal bloom ever in Lake Superior. Again, while human actions leading to chemical deposition are a key factor, the warming of this generally cold lake is a multiplier of algal blooms. See https://www.mprnews.org/story/2018/08/14/scientists-investigating-unprecidented-algae-bloom-in-lake-superior.
If even large and remote lakes are experiencing climate-related challenges, what about our smaller, shallow lakes surrounded by development, headwater streams, and wetlands? Are they heating up more quickly? Is changed rainfall impacting stream flow and wetland health? Ontario needs to apply the pre-cautionary principle to how we are impacting the landscape of water and the future of our environment, economy, and social well-being.
Talk to you downstream,