Column: Collaboration key to new Tahoe challenges

Warming temperatures pose major challenges for Lake Tahoe's environment, communities, and the outdoor recreation that drives its economy. Research by University of California, Davis's Tahoe Environmental Research Center, University of Nevada, Reno, and Desert Research Institute clearly shows Lake Tahoe is warming.

Daily maximum and minimum temperatures at Tahoe are steadily rising. The number of days with below-freezing temperatures is declining. Lake temperatures continue to increase and were the highest ever recorded in summer 2017. These warming trends could have major impacts on Tahoe's forests, the clarity and ecology of the lake, invasive species, and the vitality of our communities as the snowpack becomes less dependable and more precipitation falls as rain.

A climate change report the United Nations released this month underscores the potential severity of these challenges in coming decades and why we must continue to work together toward solutions. The report, written by 91 scientists from 40 countries who analyzed more than 6,000 studies, finds that if greenhouse gas emissions continue at their current rate, worsening impacts will be felt as the atmosphere warms to 2.7 degrees Fahrenheit above preindustrial levels by 2040.

Some of the most serious impacts of climate change-food and water shortages, heat waves, droughts, wildfires, coastal flooding, and ecosystem damage-will be felt in parts of the globe sooner and at lower temperatures than previously forecast, according to the report.

California and Nevada are already seeing the effects through increased risk of catastrophic wildfire. Record-high temperatures, drought, forest conditions, and bark beetle outbreaks have left 129 million dead trees in California, increasing fire risk for years to come.

Fifteen of California's 20 largest fires have occurred in the last two decades. The Thomas Fire, previously the largest fire on record, burned 281,000 acres in Ventura and Santa Barbara counties in December 2017. But its record size was already eclipsed this summer by the Mendocino Complex Fire that burned 459,000 acres in Colusa, Lake, Mendocino, and Glenn counties.

This summer, the Martin Fire burned 431,000 acres in Northern Nevada, with the South Sugarloaf Fire burning another 233,000 acres.

Tahoe is not immune to these threats. Climate change is a global issue we must work together on locally. Not only to do our part to reduce greenhouse gas emissions, but to prepare Tahoe's unique environment and communities to be as resilient as possible. Here in Tahoe, many partners have been working together for years to improve our region's sustainability and resilience to climate change. The need to double down is now clearer than ever.

Partners on the Tahoe Fire and Fuels Team, including the U.S. Forest Service, state parks, and local fire protection districts, over two decades have treated 75,000 acres of forest around Tahoe's communities to thin forests and remove hazardous brush to reduce wildfire risk.

We are no longer thinking small when it comes to reducing catastrophic fire risk on the rest of Tahoe's forested acres. Through the Lake Tahoe West Restoration Partnership, TRPA and other partners are working on a landscape-scale strategy to more quickly improve forest health throughout 60,000 acres of the West Shore, an area spanning from Emerald Bay to Squaw Valley-a strategy we and others can replicate around the Tahoe Basin and throughout the Sierra Nevada. This new scale of work on forest management, wildfire prevention, and community wildfire preparedness is now essential to protect Tahoe from the kinds of cataclysmic fires we see around the West.

Partners are working to make Tahoe's transportation system better connected and cleaner with more options for sharing a ride. Expanding transit and developing shared-use paths to link neighborhoods, schools, commercial areas, and recreation sites will reduce emissions and traffic congestion.

Collaborators are building a growing network of charging stations so more people can drive zero-emission electric vehicles to, from, and around the Tahoe region, and launching pilot programs to test bike sharing, ride sharing, and on-demand shuttle services that take cars off the road.

Tahoe's future depends on all of us taking proactive, responsible actions today to reduce greenhouse gas emissions and confront climate change. There are countless ways for each of us to help make Tahoe's environment and communities more sustainable. So please join this work to help ensure Lake Tahoe remains a national treasure for future generations to cherish and enjoy.

Joanne S. Marchetta is executive director of the Tahoe Regional Planning Agency.