The impacts of wildfires on lakes were once considered limited to the runoff that occurred from denuded land the following winter. But with weeks to months of heavy smoke dropping visible particles and nutrients from decimated communities and forests on the lake, and the greatly reduced sunlight and UV radiation, attention has turned to the impacts of smoke on clarity and ecosystem health. The fact that smoke is affecting areas hundreds of miles away from the actual fire, and the increasing trajectories of fire incidence and intensity with climate change makes the problem even more concerning.
This week, while the Air Quality Index (AQI) around Lake Tahoe was reaching an unbelievable 800 (where over 300 is considered hazardous to everyone), critical new measurements were being taken on the lake. The easy measurements were those that did not need human action, such as the solar radiation and UV levels. The harder ones involved measuring the changes in algal growth rate, profiling the lake to see which wavelengths of light were being absorbed, collecting deposition buckets from mid-lake, and launching underwater gliders to track the evolving impacts over the next month.