Future of Lake Tahoe clarity in question as wildfires worsen

(AP) — When a wildfire crested the mountains near North America’s largest alpine lake, embers and ash that zipped across a smoky sky pierced Lake Tahoe’s clear blue waters.

Scientists funded by California, Nevada and the League to Save Lake Tahoe are researching lake clarity and biodiversity during and after wildfires.

The clarity of the iconic alpine lake can vary even without catastrophic wildfires.

Smoke from Northern California wildfires has cloaked the Lake Tahoe basin in some past years.

But as blazes have grown in size and intensity — partially due to climate change, scientists say — smoke from wildfires inside and outside the basin that has sat atop the lake for two to three months in the past two wildfire seasons has exceeded the expectations of many residents and tourists who flock to the deep blue lake for its clean alpine air and fragrant pine trees.

“Our bread-and-butter sources of declining lake clarity are pretty well understood,” said Allison Oliver, an ecologist at the Skeena Fisheries Commission in western Canada who studied how rivers and creeks delivered murky sediment to Lake Tahoe after the 2007 Angora Fire.

“It’s really apparent that we need to be concerned about not only fires burning in the basin that cause erosion and burn scars, but the smoke generated from massive fires outside the basin,” said Jesse Patterson, the League to Save Lake Tahoe’s chief strategy officer.