Wildfire smoke impacts lake ecosystems.

Area of Science:

• Environmental Science
• Ecology
• Atmospheric Science

Background:

• Global wildfire activity is increasing, leading to widespread smoke plumes impacting ecosystems.
• Lake ecosystems are sensitive to changes in light, chemistry, and nutrient deposition, all affected by wildfire smoke.

Purpose of the Study:

• To introduce and quantify the concept of lake smoke-days in North America.
• To assess the extent and duration of lake exposure to wildfire smoke from 2019-2021.
• To review and synthesize the impacts of smoke on lake physical, chemical, and biological processes.

Main Methods:

• Quantified lake smoke-day exposure across North America for lakes ≥10 ha from 2019-2021.
• Analyzed spatial and temporal scales of smoke plume transport and deposition.
• Reviewed existing literature on smoke-ecosystem interactions.

Main Results:

• 99.3% of North America was covered by smoke, affecting over 1.3 million lakes.
• 98.9% of lakes experienced at least 10 smoke-days annually; 89.6% had over 30.
• Some regions experienced up to 4 months of cumulative smoke-days per year.

Conclusions:

• Lake smoke-day exposure is extensive and under-recognized across North America.
• Smoke impacts lakes by altering light, depositing carbon and nutrients, and potentially introducing toxins.
• Further research is crucial to understand lake responses to increasing wildfire activity and climate change.