Warming warnings

Sierra as local water source is threatened

The slopes of mountains around Lake Tahoe show the minor snowpack and water supply with which western Nevada begins a drought summer.

The slopes of mountains around Lake Tahoe show the minor snowpack and water supply with which western Nevada begins a drought summer.

PHOTO/DENNIS MYERS

“This relates to Tahoe,” said a small, professorial man at the front of a hall at the Tahoe Environmental Research Center in Incline Village. “This climate change effect is progressing rapidly.”

So rapidly, in fact, that he said it was a threat to those who are “so dependent on Tahoe for a water supply.”

That would include Reno, Sparks, Pyramid Lake, and farmers in Lyon and Churchill County.

The speaker was Charles Goldman, the scientist who has studied Lake Tahoe longer than any other, recipient of the Albert Einstein World Prize in Science, and co-author of Limnology, a volume on the study of inland waters.

Goldman is the kind of expert people who don’t get their science from Ted Nugent or the local weathercaster listen to about climate change. And he is alarmed. It’s not just downstream water impact he worries about. It’s the impact of climate change on the entire Sierra.

It’s not that Westerners weren’t warned. Eleven years ago, five scientists wrote a paper that included language like this:

“The projected changes include much-discussed warming trends as well as important changes in precipitation, extreme weather, and other climatic conditions, all of which may be expected to affect Sierra Nevada rivers, watersheds, landscapes, and ecosystems. … it appears likely that climate change would affect hazards and ecosystems significantly and throughout the range. The riverine, ecological, fire, and geomorphic consequences are far from understood but are likely to be of considerable management concern.”

In 2011, the Endangered Species coalition called the Sierra one of the top 10 ecosystems needing protection.

There have been innumerable cautions about the vulnerability of birds in the Sierra Nevada.

A group of oceanographers wrote, “Floods from winter storms on the western slopes of the Sierra Nevada have been projected to increase in intensity in winter by all climate models that have been analyzed thus far, including models that otherwise project drier conditions.”

California’s Central Valley—the breadbasket of the West, supplier of 30 percent of the nation’s food, and one of the world’s most important farm regions—is now producing 20 percent of its normal harvests.

The Union of Concerned Scientists tried appeals to self interest: “That decline [in snowpack] is likely to affect both the timing and availability of water for drinking, agriculture, and recreation. … warmer temperatures typically increase evaporation rates and demand for water for crops. … In this scenario, ski resorts might never have enough snow to operate without snowmaking machines, and could be forced to relocate. If we make significant efforts to reduce our emissions, the ski season at lower and middle elevations could shorten by a month.”

But such warnings are no match for denial activities massively funded by right-wing or corporate organizations like Donors Trust, the Howard Charitable Foundation, the Searle Freedom Trust, the John Williams Pope Foundation, and the Sarah Scaife Foundation. In 2013, a Drexel University study found that funding to denialists from Exxon Mobil and the Kochs had mostly ended while money coming from the foundations grew.

Complicating all of this is the current drought, and enduring misconceptions in the public mind.

Sierra: high and dry

Many people believe that even if corporate and government policies can be changed, Earth will begin healing itself. But nature doesn’t necessarily work that way.

“This is why Lake Erie didn’t improve at all for years after they stopped putting fertilizer in the lake,” Goldman said.

Scientists have warned repeatedly that some climate change effects are not reversible. “Have We Passed the Point of No Return on Climate Change?” is a headline that appeared last month in Scientific American.

In terms of the Sierra, Chelsea Arnold of the School of Natural Sciences at the University of California Merced said in 2014, “What we’re seeing is that all kinds of extreme weather, including one dry winter like the one we just had, can totally change the structure of the soil. Part of that is an irreversible change. … It’s like with a raisin. You can add water, but all you’re going to get is a soggy raisin.”

The drought afflicts the area just as Nevada’s terrific population growth has gotten back to normal—above 30 percent, highest in the region—while the snowpack is at 3 percent. And there is no way to tell when the drought will end. One Western drought ran from 1928 to 1939. One particularly bad drought was only a year long—1976-1977—but it did enormous damage. Tree ring studies have similar or longer droughts before the arrival of whites. During the 1930s, drought-marked tree stumps emerged from Lake Tahoe, sparking research by Samuel Harding and later scientists suggesting that a prolonged drought allowed the forest to grow lower in the basin for decades or more.

A late-1980s, early-1990s drought was six years long. Hydroelectric power generation was compromised, trees died, farmland fell fallow, the Truckee became a trickle (one rain in the very dry Sierra washed dirt downstream, turning the Truckee to a coffee-with-cream color for days, clogging the water treatment plant), and in some cases groundwater was used beyond its recharge rate. It was also a time of widespread wildfires.

The current drought is generally dated to 2010, with an acceleration of its impacts in 2012. Even if it were to end soon, the West needs to prepare for the next ones quickly. The National Aeronautics and Space Administration has projected “droughts in the U.S. Southwest and Central Plains during the last half of this century could be drier and longer than drought conditions seen in those regions in the last 1,000 years.”

To Goldman, one of the first necessities is for trust in science to be restored. That may not be easy, given the kind of money that is being spent to make science the enemy. It would also require greater sophistication on the part of the public, to stop listening to figures who cherry-pick the science, cite only evidence that supports a pre-selected conclusion, and project short-term information into long-term conclusions.

“Short term data is very, very poor to use in ecological predictions,” Goldman said.