Sierra Summit

Conversations and observations about California's mountains

October 31, 2008
Up in Smoke - Climate Change, Ecosystems and Fire
A new study has found that wildfires are inflicting increasingly severe  damage to forest ecosystems in the Sierra Nevada - and climate change is a big reason why. 
The study in the October issue of the scientific journal Ecosystems comes in the wake of earlier work that has tied global warming to more frequent fires - and a longer fire season. 
The new study - by two U.S. Forest Service researchers and three university scientists - tracked the intensity of wildfire and found that the extent of "high severity fires" - those that destroy entire stands of forest - has grown significantly since 1984.
Part of the problem, the researchers point out, is a long-standing pattern of fire suppression that has allowed Sierra forests to grow unnaturally dense and become littered with brush and woody debris. But climate change is feeding the flames as well. "The patterns we see in the climate-fire relationship are clearly due in part of increasing temperatures," they write. 
The Moonlight Fire in Plumas County, pictured at left, is a kind of poster child for this new era of intense, destructive fire. It began during hot, windy conditions over the Labor Day weekend of 2007. By the time it was brought under control, more than one third of the fire burned so thoroughly federal officials classified it as high severity. Drive through those badly burned areas today and you see no living trees across wide swaths of terrain. Even big old ponderosa pines, such as the one pictured below, that have survived many natural, cooler fires over the past two to three centuries were killed in the Moonlight fire.
"Through their growing tendency to kill larger patches of canopy trees, contemporary fires are contributing to increasing levels of forest fragmentation," the authors of the Ecosystems paper wrote. The scorched-earth blazes also threaten to increase soil erosion and stream sedimentation and hurt natural forest regeneration, they said. And the future does not look good. 
"With peak snow-melt coming earlier, fire season lengthening, the summer drought deepening and forest fuels at possibly all-time highs, it may simply be that most low- and middle-elevation forests in the study region are ready and primed to burn," the authors said, adding:
"In light of recent alarming projections for increased temperatures ... by the end of the century, a major rethinking of current fire and fuels management strategies may be in order."
U.S. Forest Service regional ecologist Hugh Safford and remote sensing specialist Jay Miller - both based in California - led the study team.

October 27, 2008
A Hiker's Guide to Climate Change
Open any guidebook to California hiking trails and you will find a mountain of information about your next destination, most of it logistical. What I like about John Soares' new digital guidebook to northern California trails  - - is how he weaves contemporary issues into the trail mix, from conflicts over all-terrain vehicles to the impacts of climate change. 

"Here at the Northern California Hiking Trails blog, we care about climate change," John writes. "From the increased intensity of wildfires to the longer hiking season, climate change matters to hikers." As John points out, warming temperatures are contributing to the uphill migration of small mammals toward cooler, more hospitable environs and may also be a factor in the increased risk of rock slides in the high country. 

Earlier this year, I heard about that danger firsthand in a conversation with S.P. Parker, a well-known climber and mountaineer from Bishop and co-owner of the Sierra Mountain Center.

"W are getting a lot more rockfall where things are not just glued together the way they were by snow and ice," Parker said. "That is certainly what they are seeing in Europe. The Matterhorn. The Eiger - all those things are falling down because you no longer have the rock glued together by ice deep in the cracks.

"What we are doing is we are starting to do snow and ice climbs earlier in the season. Because by fall, everything thing is gone," Parker said.

To read more about the impact of climate change on hiking and camping across northern California, check out  John Soares' blog at:

John is also co-author, along with his brother Marc, of 100 Classic Hikes in Northern California.



October 23, 2008
Climate change on the web @ KQED

If you care about California's climate, bookmark this site --

A production of KQED, the Bay Area public radio and televison station, the Climate Watch web page represents a first-of-its-kind, non-governmental effort to track climate issues across the entire state. Barely one month old, it's already filled with enough material to keep you clicking and clicking - and clicking some more. Think of it as an audio (and digital) archive of all things climate - from the impact of global warming on the Sierra snow-pack to efforts to curb greenhouse gas emissions across the state and region.

Craig Miller, senior editor of Climate Watch, told me the web page was born to fill a blank spot in cyber-space. "We found there really wasn't much out there, other than government sites, that were looking at climate change from a California perspective, state-wide. So we were trying to stake our our territory.

"I think there is a real recognition that the future is the web," Miller said. "That's kind of center stage right now." 

And he is obviously the right man for the job. An independent documentary producer, Miller has written, directed and hosted several television documentaries about natural resources issues across the state, including `California Heat', a fascinating look at impact of climate change in coming decades right here in our own backyard, that aired on Sacramento PBS television station KVIE earlier this week. In 2007, he won a Northern California Emmy as a producer for writing Echoes of a Lost Valley, an exploration of California prior to European settlement.
For more about Craig and his work, go to:

The Climate Watch web page is part of a package of web pages at KQED devoted to key contemporary issues. It is funded by a four year grant from the R. Gwin Follis Foundation. 
On Friday, Miller continues his coverage with a radio segment about California's never-ending fire season. Sacramento listeners can hear it on The California Report on Capitol Public Radio, KXJZ. And of course, you will find it on the KQED Climate Watch web page, too. For a preview, check out MIller's blog at: 

"If you don't count the meltdown of the global financial system, climate change is the emerging story of the decade - and maybe our lifetime," Miller said. "It's tough to ignore."


October 22, 2008
Climate Change Denial - Alaska glaciers - Fact and fiction
Not long after my recent article on the receding glaciers of the Sierra Nevada appeared in the Bee, I received an e-mail from a reader clearly skeptical of global warming. 
"Now, Mr. Knudson, since you have run this article, will you also write and run an article telling the public about the thickening glaciers in Alaska?" he wrote.  "I think it would only be fair that you research that story and publish it!"
Fair enough. So I called up Bruce Molnia, a veteran U.S. Geological Survey research geologist  and author of the comprehensive new book, Glaciers of Alaska. 
"More than 99 percent of the glaciers in Alaska have a long-term trend of rapid retreat, thinning and stagnation," Molnia told me.  "And that 99 percent continue to retreat." 
Many, though, did thicken in their upper reaches this year as a result of heavy snowfall last winter and cooler weather over the summer. "But thickening  does not translate into growing," Molnia cautioned.  "And this summer was still pretty dramatic in terms of the rate of melting of many glaciers."
Ironically enough, the thickening - retreating flap began with Molnia himself, in particular with comments he made about the heavy snow accumulation on some glaciers in an article in the Anchorage Daily News. Very quickly, he said, global warming skeptics - including talk radio host Rush Limbaugh - were seizing upon his comments and tweaking them to fit their own agendas.
"I saw individual phrases strategically pulled out of individual paragraphs to give the impression that glaciers were not melting and ... that we are being sold a bill of goods on climate change," he said. "I was fascinated at how aggressively this was picked up and broadly it was circulated." 
"I think they are grasping for straws," Molnia said of the skeptics. "So much of the science community has come around, and even some of the more conservative Republicans  have come around and said: Yes we recognize the climate is changing."
In all, Alaska has roughly 2,000 large glaciers, Molnia said. Only about a dozen - less than one percent - are advancing, largely because of heavy snowfall in the upper portions of their watersheds. The remaining 99.4 percent are retreating. 
"Alaska as a whole is warming and these glaciers are accelerating their melting," Molnia said.
(For visual evidence, look at the photos of the Muir glacier in Alaska above. The first was taken by William O. Field in 1941; the second was taken by Molnia himself in 2004.)
And even though some glaciers began receding as long ago as 1750 from natural temperature increases, the driving force behind today's meltdown is global warming caused by the the build-up of greenhouse gases from the burning of fossil fuels, Molnia said. 
"What we're seeing is that anthropogenic  effects are accelerating the rate of melting and probably have been a factor for the better part of a century," Molina said.
To read more about Molnia's new book Glaciers of Alaska, click on this link:
And for a press release about the book, check out this link:

October 15, 2008
Feeling the Heat - New report says West warming rapidly
A report released today by the non-profit group Environment California says that 2007 was the 10th warmest year on record in the United States and that the mountain West, in particular, experienced above-average temperatures. 

In Reno, Nevada - on the eastern edge of the Sierra Nevada - the average 2007 temperature of 55.3 degrees  was four degrees higher than the 30-year average temperature (1971 to 2000), according to the report. 

Nightime lows are rising, too. In Reno, the average minimum temperature last year was 40.7 degrees - more than five degrees higher than the 1971 to 2000 average, the report said.

Warmer nights are a particular concern in mountain regions, where rising temperatures mean more rain and less snow and trigger earlier melting of snow in general. "Worldwide minimum temperatures - the lowest temperatures recorded on a given day, usually at night - are increasing at nearly twice the pace of maximum temperatures," the report said. 

The report, titled Feeling the Heat: Global Warming and Rising Temperatures in the United States, is available online at:

October 9, 2008
Yosemite climate change - new article in Science magazine
Two months ago, I spent a few days in the high country of Yosemite with U.C. Berkeley emeritus professor of zoology Jim Patton, trapping and studying one of the first-known living casualties of climate change in California, the alpine chipmunk (left).
At the time, Patton talked excitedly about an article he and others were preparing that linked the upward shift of small mammals in Yosemite to global warming. Now that paper has been published in the Oct. 10 issue of the prestigious journal Science, representing the first peer-reviewed documentation that climate change is stirring ecosystem disruption in one of the world's most iconic national parks. 
"Recent trends do not bode well for several mid- to high-elevation species" in Yosemite, the article says.
To document their findings, Patton and others relied upon an unusual source: 90-year old field notes kept by pioneering California mammalogist Joesph Grinnell and his colleagues who tromped through Yosemite in the early 20th century trapping animals and jotting down almost everything they observed in small field notebooks. To learn more, check out my recent piece in the Bee  at:

I've also blogged on the topic at:

When Patton returned to Grinnell's old trap lines in 2003 - and simultaneously consulted Grinnell's field notes -  he quickly noticed things had changed. Animals common in Grinnell's camps were no longer there. They had moved up the mountain. One was the alpine chipmunk,  which was so widespread in Tuolumne Meadows in 1915 that Grinnell's men tossed sandwich scraps to them. "They're not there now," Patton told me.  "We looked for them extensively." Indeed, the animal can today be found no lower than 9,800 feet and is running out of real estate and at risk of extinction. In the field, Patton - shown below - is a bit like the creatures he studies; he is full of energy and - at 67 - he  scampers from rock to rock and up the mountain ahead of much younger colleagues. 
What makes the Science study doubling fascinating is that researchers did not set up to explore climate change. That came later. "The most dramatic finding ... was the upward elevational shift of species. When we asked ourselves, `What changed?' it hit us between the eyes: the climate," Craig Moritz, director of the Museum of Vertebrate Zoology at U.C. Berkeley and lead author of the study said in a press release. 
Overall, the study noted, night-time low temperatures in the central Sierra Nevada region have climbed three degrees Celsius over the past century (7.4 degrees Fahrenheit) over the past century. Of 28 species monitored, half expanded their ranges upslope. The average uphill shift was just over 1,500 feet.
"These kinds of changes in community composition have been going on forever," Patton said in the U.C. Berkeley press release. "The only thing that makes this different is that it has probably happened in our lifetime. It is the speed with which these changes are taking place that gives one pause."
Patton is one of America's most accomplished mammalogists and not surprisingly a disciple of Joseph Grinnell and his Yosemite camp mates. "The impressive thing about these guys is ... what incredibly observant natural historians they were," Patton said. "In pouring over these notebooks, I keep pulling out tidbits that are amazingly perceptive. These guys where out there thinking about what they were seeing and what it meant in a larger context long before most other people."
 Science does not publish its articles online, for free. To track down the Yosemite piece, you'll have to visit your library or subscribe. Alternatively, you can read the U.C. Berkeley press release/article about the paper and research at this link:

Bee potos by Tom Knudson

October 3, 2008
The Sound of Climate Change
To hear the sound of climate change in California, click on this link:Lyell meltwater.MP3

It's true that glaciers lose water naturally to melting, but in the Sierra Nevada - and around the world - glaciers are melting far more rapidly than they are being replenished by snow - a sure sign, scientists say, of global climate change.

A recent study by Hassan Basagic and Andrew Fountain of Portland State University found that seven Sierra Nevada glaciers have declined by an average of 51 percent over the past century. And one of them is Lyell glacier in Yosemite National Park where I recently recorded the sound bite you hear at the link above - the sound of centuries-old glacial ice melting into water and rushing swiftly downhill. 
east lobe, lyell 2.jpg
Future climate scenarios suggest the east lobe of the Lyell glacier  will practically disappear by 2050. Just in case you can't get up there for one last look, here's a picture of the east lobe I took two weeks ago. 
"It's fascinating to see the change," glacier researcher Pete Devine told me. "But when you get familiar with a resource like this and you see it withering away, it's kind of sad."
And troubling, too. For just as glaciers are retreating from the Sierra, so, too, is its fabled snow-pack diminishing. 
"The most valuable resource is the Sierra Nevada is not  timber or  gold or recreation or  second homes," said Devine, who manages educational programs for the non-profit Yosemite Association. "It's the snow-pack. It's something we take for granted. The range is well-named - the Sierra Nevada, the snowy mountain range. And if it's the less snowy mountain range, that will have some challenging consequences for everybody downstream."
October 3, 2008
Juniper controversy revisited, readers' corner
junipers2.jpgMy recent report on the federal government's plan to log and burn juniper woodlands across northeast California - in the name of ecological restoration, energy independence and climate-friendly power - stirred a lively response in the comment section of the Bee's web page. Separately, I received a number of interesting responses. Here is a sampling:

Hi Tom- I read your article and appreciated the topic.  This is the same old Bureau of Land Management and Forest Service of our parents and grandparents. The underlying issue here is to make the land "more productive" for grazing.  Back in the late '60s the BLM in Nevada were employing a technique called "chaining" where they would pull a huge ship's anchor chain between two bulldozers and uproot Junipers, pines, sagebrush, archeological sites and everything else in the way for miles and miles. Then they would plant crested wheatgrass and claim that they were changing a terminal ecosystem back to a productive range. This would appear to be the same goal with different techniques and scientific cover.

Not sure about the carbon storage issue. Hard to believe sage and grass would store more carbon than Juniper trees. But what do I know!


Eddie Hard, Rosemont



 I am always amazed at how things are rationalized. A recent study was done on the Forest Service. One outcome was that the majority of Forest Service personnel completed college more than 20 to 25 years ago. Concepts and understandings of ecosystems, including juniper ecosystems have changed, while the Forest Service continues the mantra of "EIS, clear cut, burn, pave it over, and paint it green." No rational person intentionally creates moonscapes. As Aldo Leopold said, you can read the health of an ecosystem in the landscape. These horizontal "modified" juniper forests don't appear to be healthy, nor are they able to sequester carbon. This is all in the quest of more non-native grass for grazing. The native grasses were Nassella (formerly the genus Stipa) or purple needlegrass. Removing junipers just ensures invasion by non-native grasses - less nutrition, diversity and resilience.

 Juniper invasions occur when fire is excluded. Fire has been suppressed for about 100 years. So now we are reaping "old growth" junipers that would not have survived fire as seedlings. Integral reoccurring wildland fire is threatening to many foresters - they still buy into the Smokey Bear myths. Even when you use an increment borer to core into trees to identify and date periodic fire episodes, foresters refuse to accept what the evidence shows. Episodes such as this always seem to happen "just out of the public view." This occurred on the Sequoia National Forest where multiple Sequoiadendron (Sierra Big Tree) groves were aggressively logged on eastern-facing slopes (away from the common public view). It was Martin Litton and a few others, who noticed the unusual clear cuts - with snow on the ground - from the perspective of a private plane. The Forest Service ignored its own designations of "protected" groves, dragged logs across sensitive roots, and made a general mess of things. A critical result was the establishment of Giant Sequoia National Monument - and still the Forest Service cannot understand or believe things have changed. The effort now is to get the monument out of Forest Service and into National Park Service hands for proper management.

 Scott Kruse, Fresno


Hi Tom,

The idea that a massive disturbance like a fire, chaining and burning, spraying, etc. is going to return a site to original productivity for anything other than a short term, in even an arid (not increasingly arid) environment, is the opposite of what research around the world shows.  Has anyone done an honest check on the progress/status of the massive crested wheatgrass plantations that were developed in Nevada's Basin and Range country since the 1960s?  A follow-up investigation of what happens with post-treatment plant communities from other 'management' disturbances in the Great Basin could prove illuminating.  What interesting times we are in.  Regards, Ray Butler, Truckee


Tom -

  When I first heard of this juniper cut it was two years ago and at that time it was all about re-establish the grasses that had been lost to over grazing.  It seems the junipers were able to take over after the cattle had grazed off all the other vegetation.  Cattle don't care for juniper.  This is an example of a huge problem facing land management in the west, poor grazing practices not only from the past but still being practiced today.

I guess what I'm trying to say is without the poor grazing practices of the past there would never of been a story of having to cut down juniper forests today.

Steve Robinson, Westwood




October 2, 2008
Living History - Remembering Joseph Grinnell
Seven decades ago, Elmer Aldrich of Sacramento (left) spent a few weeks in the Mojave Desert with one of California's most famous naturalists, Joseph Grinnell.  They camped, collected specimens for U.C. Berkeley's Museum of Vertebrate Zoology and took a lot of notes. 

Today, Grinnell's detailed notes from his collecting expeditions across California have become an invaluable source for climate change researchers, showing, among other things, that alpine chipmunks and other small mammals in Yosemite National Park have retreated higher into the mountains over the years in search of cooler, more hospitable climes. 

Grinnell died in 1939 - and Aldrich is one of a handful of people still alive who studied under him and worked with him in the field.
This weekend, Aldrich - who is now 94 - will recount his experiences with the legendary naturalist in a talk at the Berkeley museum, including his collecting expedition with Grinnell to  the Providence Mountains in the Mojave Desert in 1938. "Way before the word ecology was hardly used, Grinnell was one of the best ecologists I ever met and worked with," Aldrich told me recently. 
"He was all business. When he was there with us, things became very orderly. He organized everything. We had set times for breakfast and dinner and we had a meeting after every breakfast."
Grinnell's strategy, Aldrich elaborated, was to document almost everything he observed outdoors because the value of such records might not be clear until many years later. Today, it is that treasure trove of old field notes that scientists like U.C. retired zoologist Jim Patton and others are beginning to mine for fresh insights about global climate change. 

During our phone conversation, I asked Aldrich if he believed in global warming.

"Oh, absolutely. Absolutely," he said. "I've noticed it myself in climbing to higher altitudes." Specifically, he mentioned that a small cold-loving cousin of the rabbit - the pica - is growing scarce above timberline in the Sierra Nevada. It's the same thing that is hurting the polar bear, he said. In short, living things that depend on colder temperatures - including many here in the Sierra - are going to diminish, Aldrich said.

Bee Photo by Autumn Cruz

October 1, 2008
Sierra Nevada glaciers - going, going, gone?
greg re-do.jpg
Recently, I spent a few days in the field with Greg Stock, geologist for Yosemite National Park, checking on the health of the Lyell glacier, the second largest permanent ice sheet in the Sierra. Greg (left) told me many things about the Sierra's 100 or so glaciers, but nothing struck me more than his grim prognosis for them. "Given the amount of change we've seen even over the past few decades, I think it's safe to say that those glaciers will be gone in 100 years. They may even be gone in 50 years and there's a chance that some of them will be gone in 20 years," Greg told me. The problem, in Greg's view, is global climate change - in particular rising CO2 levels caused by the worldwide burning of fossil fuels that are causing temperatures to climb. This is not the first time that Sierra glaciers  have receded.  But this retreat is different. "I think the fundamental thing that makes the melting of today different than the melting of the past is that almost certainly humans are causing it," Greg said. Watch for my upcoming report in the Bee about the Sierra's receding glaciers and what Greg Stock and other visitors to Yosemite's high country have to say about them. 

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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