Sierra Summit

Conversations and observations about California's mountains

August 30, 2008
Responding to climate change

Not long ago, I interviewed William "Bill" Tweed who recently retired as chief of interpretation at Sequoia Kings Canyon National Park. 

Like most Sierra naturalists, Bill is very concerned about climate change and believes major changes are inevitable for the Sierra Nevada and its diverse array of ecosystems. 

But as we wrapped up the interview, he took a different approach to the subject and spoke not about the threat of climate change but our response as a society to it. I found his observations intriguing and have included them here. 

"Scientifically, we understand climate change," Bill told me. "But we haven't got the body politic to understand it. The challenge of global climate change is not to understand what we are doing to the planet. It's to try to change how we respond to what we have learned.

"We live in this bizarre society, this strange society, where we happily accept science that gives us toys and pleasures and we consistently reject science that challenges us to think about limiting and controlling ourselves. But it's the same science. We just pick and choose. The same people who happily sneer at global climate change are fascinated by what comes from the Hubble space telescope."

August 26, 2008
Forests and climate change
You won't find the Journal of Forestry for sale on your supermarket shelf, but if you care about trees, you might want to visit your library and check out its June 2008 edition. 

     There will find an article about climate change and forests by retired U.S. Forest Service chief Dale Bosworth and three other researchers, including Connie Millar, a research paleoecologist with the Sierra Nevada Research Center of the U.S. Forest Service. 

       With conifers already under climate stress in the Sierra Nevada and mortality rates on the rise, too - the article is nothing if not timely and sobering. And credible, too. The Journal of Forestry - the official publication of the Society of American Foresters - is the most widely circulated scholarly forestry journal in the world.

 "Average temperatures in the Northern Hemisphere have reached their highest level in 400 years and probably in a 1,000 years," the authors point out, "and they continue to climb." But that is just the prelude. As the article states:

"If carbon dioxide levels double in the 21st century (a distinct possibility), they will reach the highest concentrations in the past 80 - 100 million years. When Earth last saw such high levels of atmospheric carbon - during the Cretaceous Period, when forests were dominated by tree ferns and palm-like cycads - it was a very different place." 

"Climate change will likely be too rapid for today's forests to maintain their current structure, functions and composition, given the landscape impediments that people have created," the authors write. "Land managers will face a high and growing risk of loss of local species populations as well as widespread tree mortality and increased threats from ecological stressors such as wildfire, insects, diseases, air pollution and invasive species."

The title of the article is "Climate Change and the Nation's Forests: Challenges and Opportunities." One of the biggest opportunities, it points out, is finding ways to market the carbon that trees sequester naturally. Another hope, it says, is "facilitating the removal and use of excess forest biomass for biofuel and providing incentives to increase the area of biomass energy plantations."

"There is hope," the authors say in wrapping up their piece. "We can ... modify a broad range of forestry activities to reduce greenhouse gas emissions and increase carbon sequestration. However, implementing these modifications on a broad scale while continuing to produce forest goods and services will be a formidable challenge."
August 22, 2008
In Yosemite, old notes yield new insights on climate
Joseph Grinnell, the founding director of U.C. Berkeley's Museum of Vertebrate Zoology, was a fanatic about taking notes. Put it all down, he would say. You might not think it's important but someone may. 
Today, Grinnell's detailed, nearly century-old field notes about chipmunks and other small mammals in Yosemite National Park are revealing new insights about climate change in the Sierra Nevada, a subject I explore in an article in this Sunday's Bee. 
Click on this link and step back in time as a colleague talks about Grinnell's archival obsession in the wilds of California:

Believe it or not, you can even read Grinnell's hand-written Yosemite journals on line. They're available at: 

August 5, 2008
On snow and 'conies' - old science, new insights in the Sierra

The mountain I climbed Sunday near Lake Tahoe offered a remarkable view of the Sierra Buttes, the north fork of the American River, even the Coast Range far to the west.

But it was a brief entry in the peak's summit register that really caught my attention. On Oct. 7, 2002, a hiker from Orangevale jotted the following observation in a small notebook and left it on the mountain in an ammo can: "Not much snow left on the mountains."

You know what? I could have written the same thing Sunday - and we're not even close to October.

Snow is melting fast from the Sierra Nevada nowadays - just one of many signs that global warming is already taking a toll here in our own backyard. This week, I'm visiting Yosemite National Park to check in with a team of scientists investigating another piece of the climate change puzzle - the movement of small mammals - from mice to marmots - upslope toward cooler locales.

One of the cutest and most severely impacted of such species is the pica, also known as the Yosemite cony. In some locations, conies have virtually disappeared from their old haunts.

In July 1915, C.L. Camp, a member of the pioneering Joseph Grinnell expedition, sketched a Yosemite cony in his notebook - a drawing that - believe it or not - you can see on-line at (Camp didn't miss much; he drew the cony from the side, staring straight ahead, even barking!): &scan_directory=v557_s3&section_order=3&page=182&orig_query=331078

What climate change lessons will scientists in Yosemite today draw from re-surveying Grinnell's old camps and comparing notes? Stay posted for future reports.

August 3, 2008
Higher and Hotter - Climate Change in the Sierra Nevada
Climate change is here. It's happening now.

Time and again, that's what I heard while traveling more than 3,000 miles across the Sierra Nevada and northeast California this spring and summer.

In Quincy, Bishop, Truckee, El Portal and scores of other places, people told me their stories - about shorter winters, longer summers, drier lakes, earlier snowmelt, dying conifers, more destructive fires, deeper and drier wells, plants blooming earlier and a lot of other things.

Such accounts mesh with a flurry of recent scientific reports that suggest global warming is taking root in the Sierra and other high elevation landscapes across California and the West - and that the implications may be profound.

On this page, I will track this changing landscape, posting updates from the annals of science and dispatches from the field. Here, and in the paper, I will explore not only how global warming is changing the Sierra but what's being done to slow it down - or adapt to it. Like many people, I want to know what works - and what doesn't.

I want to hear from you, too. What are you seeing? What are you hearing and reading? How is climate change affecting you - and people you know? Do you have historical photoes, diaries or other information that reveal climate changes over time? Think of this Web page as an electronic climate change bulletin board for the Sierra Nevada, a place to check periodically for the latest news and to offer your own observations as well.

To contact me directly, send me an email at and let me know how to get back in touch with you. If you'd like to submit historical photos depicting terrain that has changed, send those to
August 3, 2008
Yosemite Ranger Bob Fry Remembers


For more than four decades, Bob Fry was one of the most popular, recognizable rangers in Yosemite National Park. To many, his passion for Yosemite was infectious, his knowledge of its plants, animals and geology encyclopedic.

Now retired, the 78-year-old Fry spends his summers at his home in Groveland, west of the park, where I met him one quiet June afternoon. After all those years leading tourists around the park, Fry seemed a little lonely - eager to talk.

And talk we did, well into the night - and again the next morning. It was hard to get him to stop. My notebook quickly filled up with Bob's observations over the years,from changing hibernation patterns to vanishing amphibians to fewer cold snaps, more high-altitude forest fires and far fewer summer thunderstorms. He talked about those storms a lot: the darkening sky, jagged streaks of lightning, sharp clap of thunder and rain that pelted down in leaden sheets. He missed those storms - the sound and the fury of summer in Yosemite.

As I left, I asked Bob to jot down some of his remembrances,as a kind of ranger's diary of change over time. A few days later, I got an e-mail:

August 3, 2008
Kelly Redmond - Go-to Climate Change Scientist

Denial ain't just a river in Egypt
- Mark Twain

A journalistic endeavor like this is sure to rile critics who say that climate change is just another natural cycle in the long history of the Earth.

And that reaction is itself perfectly natural, said Kelly Redmond, deputy director of the Western Regional Climate Center in Reno. After all, weather in the Sierra Nevada is always changing - often wildly so - making subtle patterns that roll out over time difficult to detect.

"Human beings are built to notice variation," said Redmond.

"When stuff happens chronically, we get used to it so quickly we hardly notice. Most people won't tell you: 'You know, it's about six-tenths of a degree warmer than when I was a kid.' "

Redmond has walked that road himself. Once, he was a global warming skeptic, too.

But today, he wears a new hat: He is the go-to guy for data about climate change in the Sierra Nevada.

About Sierra Summit

The Author
Tom Knudson lives in the Sierra Nevada and travels widely throughout the range. His hobbies include fly-fishing, backpacking and cross-country skiing. He is the recipient of numerous journalistic awards, including two Pulitzer Prizes, one for a 1992 Sacramento Bee series "Sierra in Peril," a watershed work about environmental threats to the mountain range. E-mail Tom at

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