Lake Tahoe has had a record-breaking year — and not in a good way.
A team of scientists from the University of California, Davis (UC Davis) has revealed in a new study that Lake Tahoe is getting warmer at a rate that is 15 times faster than its historic average.
In a new State of the Lake report, researchers say Lake Tahoe's rising water temperatures are threatening the lake's iconic clarity by affecting many features of its ecology.
Professor Geoffrey Schladow says the incidence of rising air temperatures at the lake has been known for many years now, as well as the warming waters.
But what's different this time is that scientists are seeing more aspects of Lake Tahoe's internal physics changing.
"[T]hat is bound to alter the ecology," says Schladow, who is the director of the Tahoe Environmental Research Center (TERC).
High Water Temperatures
When researchers began keeping records of the lake's water temperature in the 1970s, the lake had an average of 50.3 degrees Fahrenheit (10.17 degrees Celsius) year round.
In 2015, Lake Tahoe averaged 53.3 degrees Fahrenheit (11.83 degrees Celsius), the report says.
Although the increase may appear statistically insignificant, scientists say much of the warming happened in the past decade and a half. This sign has left experts concerned.
The increasing water temperatures may likely be linked to shifting air temperatures. Scientists have detected a daily air temperature increase of 4.3 degrees Fahrenheit on the northwest shore of Lake Tahoe since 1916.
Waters with different temperatures mix deep in the lake during the winter. This mixing often leads to a clearer view.
However, Lake Tahoe did not mix at its maximum depth this year, which scientists blame on the warmer influx of water. Water clarity dropped to 73.1 feet in 2015 — almost a 5-foot decrease in recent years.
Furthermore, swimmers have observed algal blooms spread on the lake in previous years. Experts say longer algal blooms have been associated with climate change because algae likes warmer water.
Effects Of Climate Change
What is happening at Lake Tahoe is not only alarming for tourists who use the lake for recreation, but also for those concerned about the impacts of climate change to the beauty of natural resources, researchers say.
Lake Tahoe is unique, but scientists explained that the forces and processes that affect it are the same as those that act in most natural ecosystems.
Because of that, Lake Tahoe is a microcosm of other natural systems in the Western United States and around the world.
Keep Lake Tahoe Healthy
How can residents and tourists keep the iconic lake as healthy as possible?
Experts say attention to the lake's natural filtration systems as well as stormwater collection may help prevent harmful substances that accelerate the growth of algae such as phosphates out of Lake Tahoe.
Darcie Goodman Collins, director of the League to Save Lake Tahoe, believes not much can be done to manipulate global warming.
"But we can influence the lake's health," Goodman Collins added.
Meanwhile, the UC Davis "Tahoe: State of the Lake" report can be read and downloaded (PDF) from the university's website.
Photo: Chris Yunker | Flickr
