Saturday, April 12, 2025

Do You Think You Know the Highest Waterfall in Yosemite Valley? You Could Be Wrong!


Quick quiz: What is the name of this waterfall?
What is the highest waterfall in Yosemite Valley? Depending on the parameters one can use to determine "height", your assumption may be wrong! Most "authorities" recognize Yosemite Falls (2,425 feet/739 meters) as the highest in Yosemite Valley and North America, and somewhere around the fifth or seventh highest in the world. But it depends on how you decide to measure waterfalls. By a different metric, Yosemite Falls isn't even the highest waterfall in Yosemite Valley. It's the word "falls", in the plural, that makes the difference.

I was in Yosemite Valley yesterday, and the falls were flowing strong. There is no doubt that Yosemite Falls is one of the most stunning sights on the planet. A chance movement of a glacier 13,000 years ago forced a middling stream from its old channel to the left of the current waterfall, forcing Yosemite Creek to drop right off the edge of the sheer cliff. You can see the old channel almost hidden in the shadows in the photo above.
The fall makes a sheer plunge of 1,430 feet (440 meters) at the Upper Fall and then cascades through a series of steep ledges called the Middle Cascades for 675 feet (206 meters). There is a final drop of 320 feet (98 meters) at Lower Yosemite Fall. The Middle Cascades are generally hidden from view unless you hike the steep trail up to the top of the falls (below).
Part of the Middle Cascades (April 2003)
But if one decides to be a purist about such things, one can define a waterfall's height on the basis of the greatest freefall. By that metric, Yosemite Falls still is an imposing 1,425 feet (739 meters) high. But it also means it's not even the tallest waterfall in Yosemite Valley.

Many first-time visitors to the valley are drawn to Bridalveil Falls (620 feet/189 meters) because it is the first major waterfall visible as one enters the valley. But when standing at the base of Bridalveil, they may see another high waterfall across the valley west of the sheer cliff of El Capitan and wonder if it is Yosemite Falls. It's not. It's called Ribbon Fall, and it has a single drop of 1,612 feet (491 meters). That's nearly 200 feet higher than Upper Yosemite Falls (it's the one in the picture at the top of the post). It is less familiar than many of the other waterfalls because it is usually dry by June when the majority of people visit the park. But if you get the privilege of seeing by visiting in the spring, you are in for a treat.
Ribbon Fall (1,612 feet) to the left with the 2,900 foot cliff of El Capitan to the right

Ribbon Falls is one of many treasures that make a spring visit to Yosemite Valley a worthwhile endeavor. If you want to see another springtime waterfall over a thousand feet high, check out Sentinel Falls.

Tuesday, April 8, 2025

The Most Extraordinary Landscape on Planet Earth: Geotripping on the Colorado Plateau, June 3-17, 2025

Horseshoe Bend on the Colorado River
NOTE: This is an updated and revised version of a post from December 28, 2024 

So...about that bucket list of yours. 

Surely you have one. If you don't, what's keeping you from making one? Here's a version I promoted a few years back (I've made it to around 70% of them so far and feel exceedingly lucky to have been able to do so).

In any case, how many of the following are (or should be) on your personal list? Possibly Grand Canyon, Zion, Bryce Canyon, Arches, Petrified Forest, Capitol Reef, Yosemite, Great Basin, or Canyonlands National Parks? What about Ancestral Pueblo cliff dwellings at places like Bear's Ears or Grand Staircase-Escalante? Finding ancient petroglyphs along the Colorado River? Or searching for dinosaur bones? How would your life be changed if you could somehow do all these things...in one trip? It's possible!
Grand Canyon National Park
There is no place on this planet like the Colorado Plateau. It's hard to find anyplace else on Earth where the crust remained relatively stable for upwards of a billion years, accumulating several miles of horizontal sediments, only to be lifted up rapidly in the last few million. The Colorado River and her tributaries then stripped away much of the sedimentary cover, and cut deep into the underlying metamorphic rocks. Those metamorphic rocks record a violent geologic history of colliding landmasses and mountain-building. The resulting landscape is one of the most beautiful regions imaginable.
Angels Landing Trail in Zion National Park, Utah
The plateau country is a training ground for geologists and earth scientists, and has been since the days of John Wesley Powell and Joseph Ives, who were the first to lead research parties into the region (they didn't "discover" the plateau, of course; Native Americans have known the region for thousands of years). If you are curious about learning geology in this incredible region, you might consider joining us as a student (of any age) on our geology field studies course Geology 191: Geology of the Colorado Plateau, offered under the auspices of Modesto Junior College in Modesto, California. The course is designed to fulfil the curiosity and build the skills of lay geologists and archaeologists as well.
Mesa Arch in Canyonlands National Park
Our field course will be a grand loop through the plateau country, with investigations of the Mojave National Scenic Preserve, Grand Canyon, Zion, Bryce Canyon, Arches, Canyonlands, Petrified Forest, Capitol Reef, Great Basin and Yosemite National Parks, as well as many monuments, including Bear's Ears, Grand Staircase-Escalante, Natural Bridges, and Navajo. It will be an unforgettable two week trip from June 3-17, 2025, beginning and ending in Modesto, California. Check the first comment to this post for information about the itinerary and our organizational meeting on April 21, 2025 (by Zoom).
Petroglyphs on the plateau
It's not a comfortable trip...we travel in school vans (which of course are known for their luxuriousness!), we camp every night, and the days can be hot, windy, cold, or stormy, and we are out in the middle of anything that happens. But we are staying in beautiful places each night, and there are even showers and laundry available every third day or so! Extensive hiking is not required, but there will be many chances to explore the trails in each park and monument.
Petrified Forest National Park
Geology 191 is a 3-semester-unit course. By end of the course, you will be able to see the landscape the way geologists do: by identifying rocks, minerals and fossils, and interpreting the geological history of an area by working out the sequence of events as exposed in outcrops. If you are a science teacher, you will come home with a collection of photographs that illustrate most of the important principles of geology, and a selection of rocks, minerals and fossils that will make a great classroom teaching tool (legally collected, of course; there are many localities outside of protected parks from which to collect samples). You will also gain some mastery of the archaeology and culture of the plateau region, the home of the Ancestral Puebloans, the Fremont people, the Navajo, the Utes, and others.
Canyonlands National Park, Utah

The cost of the trip will be $850 plus the cost of tuition (Currently $46 per unit for California residents, and around $307 per unit for out-of-state residents). The cost includes transportation, food, camp fees, and entrance fees. Participants would want to bring a few dollars along for showers, laundry, and souvenirs.  The food is tasty and plentiful (everyone helps cook and clean!), and the school vans...are vans.
House-on-Fire Ruin, Bear's Ears National Monument

If you are not in the area, we will be glad to arrange for transportation from nearby airports and train stations (we actually have an Amtrak station in town). Enrollment can be completed online once you are registered with the college (http://www.mjc.edu). Please contact me with any questions you may have.
Bryce Canyon National Park
Hope to see you out there, back of beyond!

Friday, March 14, 2025

The First Lunar Eclipse of 2025


Interesting skies once again! Tonight was a lunar eclipse. The timing was great, with totality being reached before midnight here in the Pacific Time Zone. But we are in the midst of a powerful Pacific storm, and I thought I wouldn't have a chance because of the cloud cover.
A lunar eclipse occurs when the Earth ends up passing between the Sun and the Moon, and thus casting a shadow across the Moon's face. Lunar eclipses last longer than Solar eclipses because the Earth casts a much larger shadow, and it takes longer for the Moon to pass through it. 
The most interesting part of a Lunar eclipse is during totality when the darkened Moon picks up a faint red glow (the "Blood Moon"). Numerous stars are usually visible at that time, being normally invisible when the Moon is full and bright.
Clouds moved in and I figured the Blood Moon view was not going to happen and I came in the house and started writing up the post. I took one more trip outdoors and was treated to the total eclipse. I could have hoped for a better shot, but no one here is complaining as the next storm moves in.


Thursday, February 20, 2025

An "Extinct" Fish Finds Life Again in a Parched Desert: The Saga of the Shoshone Pupfish

The pupfish habitat at the springs in Shoshone, east of Death Valley National Park
Of all the things one might look for while exploring intense desert environments, what is the most unlikely form of life you would expect to encounter? Fish of course. It's practically an oxymoron to use the term "desert fish". But in the harsh desert environments of eastern California and western Nevada, there are indeed fish. And not just a single species, but around a dozen species and subspecies. There are nine distinct populations of the Cyprinodon Pupfish, three species of Speckled Dace, and a Poolfish. How they survive today, and how they got there in the first place is a fascinating story.

How they survive is not difficult to understand: despite the aridity of the California desert, there are sources of water. There are permanent springs and pools of water scattered all around Death Valley and the Amargosa River Basin, and the fish have adapted to life in waters that might be hot, cold, fresh, or salty.


How they got there in the first place is a little trickier to understand. Our climate has been subject to huge variations over the last two million years, and more than a dozen times, it got much cooler and glaciers developed and expanded, especially in the Sierra Nevada mountains. Some of the meltwater from those glaciers flowed into the deserts of the Basin and Range province and accumulated in huge freshwater lakes. As a lake basin filled (such as at Mono or Owens Lake), it spilled over into the next lake basin until a network of lakes extended from the Sierra Nevada to Death Valley. The Amargosa River flowed through western Nevada, also ending in Death Valley. So there was plenty of water once upon a time.

At some point in time, a connection was made with the Colorado River, and fish were able to make their way into the network of freshwater lakes, and they thrived. But as each glacial stage ended, the lakes would begin drying up and most of the fish lost their habitat and went extinct. But those very few species that could adapt quickly enough took refuge in the rare and isolated springs and pools. A few, including the Lahontan Cutthroat Trout survived in the cold streams, lakes and rivers of the eastern Sierra Nevada. Those trapped in saline waters had to adapt to the salty conditions. Some fish adapted to high temperatures,  and unlike pretty much any other fish in the world can survive in water that reaches a hundred degrees or more.

One of my very few photos of the Devils Hole Pupfish, taken from around 100 feet away.

Perhaps the most famous of these fish is the Devils Hole Pupfish (above), found in a single cavern opening in the Ash Meadows National Wildlife Refuge (the spring officially lies in an outlier of Death Valley National Park). Their story is compelling, but they are not the fish I'm discussing today. You can read about them if you wish here or here.

 
The various populations of pupfish survived for thousands of years in isolation from human developments. But the colonization and occupation of the desert by miners and ranchers spelled doom for some of them. One species, the Tecopa Pupfish, was driven extinct pretty much in an afternoon when pipes were installed at the one spring where they lived. A similar fate apparently happened to a different subspecies, the Shoshone Pupfish (Cyprinodon nevadensis shoshone) in the 1960s as springs in that area were developed for domestic use at the village of Shoshone. The species was declared extinct in 1969, as none could be found anywhere.
Improbably, a small population of the fish actually survived the devastation of their original habitat by taking refuge in a nearby irrigation ditch, unnoticed by anyone. In 1986 they were rediscovered, and a cooperative effort by the private landowner and several environmental organizations resulted in a resurrected habitat. This habitat was actually expanded to three pools and some artificial off-site refuges as well. Despite visiting Shoshone yearly for the last three decades, I never heard about the efforts being made on behalf of the fish's well-being. 
That changed last week when I found out that a nature trail had been constructed, and interpretive signs posted that allowed for some close viewing of the diminutive fish (as well as another highly endangered creature, the Amargosa Vole). The site also serves as an excellent habitat for a large variety of birds, and we saw Western Bluebirds, Yellow-rumped Warblers, White-crowned Sparrows, a Costa's Hummingbird (a life-lister for me) and we could hear Verdins chattering away in the brush.
The trail is just off the main highway in Shoshone, and the locals seem proud of the efforts and can easily point the way to the trailhead, next to the local school. If you ever travel to Death Valley from the east, you can't miss the town. It's the only gas station and food stop for many miles. Don't forget to stop in at the local museum for a look at the Columbia Mammoth fossils on display inside!

 

Monday, December 30, 2024

Strange Doings in the Sky Today. What the Heck is a Circumzenithal Arc?

We live our lives never truly knowing when the day comes that something remarkable happens. I was doing totally normal errands today in the middle of town when I saw a sun dog, a common enough occurrence, but it was so bright I decided to snap a shot. But as I got out of the car, I realized something more complex had become visible, something I'm fairly sure I've never seen before. The sun dogs were connected to a halo around the sun, but at the top was an "upside-down" rainbow, like a giant smile in the sky.
I made use of a highly technological sun-blocking tool that I have in my pockets sometimes to try and bring out the colors a little better. In my capacity as an earth science instructor I generally teach about climate and weather, but phenomena related to the refraction of light off hexagonal ice crystals in the upper atmosphere gets lost in the concerns over global climate change and that sort of thing. So I haven't kept up the finer details of atmospheric refraction effects, and had to get a refresher about what I was seeing.

Source: Meteorology Today by Don Ahrens

There were five phenomena happening at once here, all related to the refraction of light in ice crystals in the upper atmosphere: a 22 degree halo, part of a 46 degree halo, two sun dogs, an upper tangent arc, and high above, the circumzenithal arc (the upside-down "rainbow"). I read that the arcs are not uncommon, but are noticed less because they tend to occur overhead where people don't tend to look. I didn't see it myself until I stopped on the way home to try and catch the arc again. It can be seen in the picture below.

Beautiful things can find you any time. You just need to watch for them!
 

Saturday, December 28, 2024

About That Bucket List...What Would You Do To See These Places?

Horseshoe Bend on the Colorado River
So...about that bucket list of yours. 

Surely you have one. If you don't, what's keeping you from making one? Here's a version I promoted a few years back (I've made it to around 70% of them so far and feel exceedingly lucky to have been able to do so).

In any case, how many of the following are (or should be) on your personal list? Possibly Grand Canyon, Zion, Bryce Canyon, Arches, Petrified Forest, Capitol Reef, Yosemite, Great Basin, or Canyonlands National Parks? What about Ancestral Pueblo cliff dwellings at places like Bear's Ears or Grand Staircase-Escalante? Finding ancient petroglyphs along the Colorado River? Or searching for dinosaur bones? How would your life be changed if you could somehow do all these things...in one trip? It's possible!
Grand Canyon National Park
There is no place on this planet like the Colorado Plateau. It's hard to find anyplace else on Earth where the crust remained relatively stable for upwards of a billion years, accumulating several miles of horizontal sediments, only to be lifted up rapidly in the last few million. The Colorado River and her tributaries then stripped away much of the sedimentary cover, and cut deep into the underlying metamorphic rocks. Those metamorphic rocks record a violent geologic history of colliding landmasses and mountain-building. The resulting landscape is one of the most beautiful regions imaginable.
Angels Landing Trail in Zion National Park, Utah
The plateau country is a training ground for geologists and earth scientists, and has been since the days of John Wesley Powell and Joseph Ives, who were the first to lead research parties into the region (they didn't "discover" the plateau, of course; Native Americans have known the region for thousands of years). If you are curious about learning geology in this incredible region, you might consider joining us as a student (of any age) on our geology field studies course Geology 191: Geology of the Colorado Plateau, offered under the auspices of Modesto Junior College in Modesto, California. The course is designed to fulfil the curiosity and build the skills of lay geologists and archaeologists as well.
Mesa Arch in Canyonlands National Park
Our field course will be a grand loop through the plateau country, with investigations of the Mojave National Scenic Preserve, Grand Canyon, Zion, Bryce Canyon, Arches, Canyonlands, Petrified Forest, Capitol Reef, Great Basin and Yosemite National Parks, as well as many monuments, including Bear's Ears, Grand Staircase-Escalante, Natural Bridges, Navajo, and Hovenweep. It will be an unforgettable two week trip from June 3-17, 2025, beginning and ending in Modesto, California. Further information will be found soon here and at my school website. 
Petroglyphs on the plateau
It's not a comfortable trip...we travel in school vans (which of course are known for their luxuriousness!), we camp every night, and the days can be hot, windy, cold, or stormy, and we are out in the middle of anything that happens. But we are staying in beautiful places each night, and there are even showers and laundry available every third day or so! Extensive hiking is not required, but there will be many chances to explore the trails in each park and monument.
Petrified Forest National Park
Geology 191 is a 3-semester-unit course. By end of the course, you will be able to see the landscape the way geologists do: by identifying rocks, minerals and fossils, and interpreting the geological history of an area by working out the sequence of events as exposed in outcrops. If you are a science teacher, you will come home with a collection of photographs that illustrate most of the important principles of geology, and a selection of rocks, minerals and fossils that will make a great classroom teaching tool (legally collected, of course; there are many localities outside of protected parks from which to collect samples). You will also gain some mastery of the archaeology and culture of the plateau region, the home of the Ancestral Puebloans, the Fremont people, the Navajo, the Utes, and others.
Canyonlands National Park, Utah

The cost of the trip (still to be officially determined) will be $850 plus the cost of tuition (Currently $46 per unit for California residents, and around $225 per unit for out-of-state residents). The cost includes transportation, food, camp fees, and entrance fees. Participants would want to bring a few dollars along for showers, laundry, and souvenirs.  The food is tasty and plentiful (everyone helps cook and clean!), and the school vans...are vans.
House-on-Fire Ruin, Bear's Ears National Monument
For those of you who live in the Modesto region, we are having an organizational meeting in April which will also be available as a Zoom session. Details will be provided later on.

If you are not in the area, we will be glad to arrange for transportation from nearby airports and train stations (we actually have an Amtrak station in town). Enrollment can be completed online once you are registered with the college (http://www.mjc.edu). Please contact me with any questions you may have.
Bryce Canyon National Park
Hope to see you out there, back of beyond!

Wednesday, December 25, 2024

The Simultaneous Seasons of California (and a peek at Half Dome)

It was a beautiful Christmas day here in the Central Valley, one of the prettiest I can recall. The storm that blew through yesterday was gone, and the winds were enough to prevent the fog from setting in. I took a walk along the Tuolumne River Parkway Trail in Waterford, and was gifted one of those rarest of things: a clear view of the beautiful Sierra Nevada. And of course it was the moment of three simultaneous seasons of California.


Yes, it's that time of year in California when three seasons occur at once. Sure, the calendar says it's winter and all, and that is certainly true in the high country of the Sierra, buried under feet of snow. But here in the valley, the last leaves are finally falling from the Valley Oak trees along the river, but with the rain has come the promise of spring as the grass sprouts and spreads a layer of green along the bluffs above the Tuolumne River.

The gift of enjoying the panorama of the Sierra Nevada Crest is rare in our valley. Although my little town sits at the very edge of the Sierra Nevada foothills, the mountain range is a tilted block of crust that slopes gently westward. As a consequence, the high peaks of the Sierra Nevada lie 40-50 miles away. The view of the peaks is generally obscured most of the time, for reasons both natural and artificial. In winter, an inversion layer develops that keeps a barrier of fog and mist that prevents any viewing of the mountains. In the summer and fall, dust and smog obscure the view. It is most often at the end of storms that the mountains are revealed in their full glory like they were today.

The Tuolumne River is one of the two main rivers that drain Yosemite National Park (the Merced River is the other. So the view from my trail encompasses much of the roughly 1,000 square miles of the park (for perspective, Yosemite Valley itself is only about 7 square miles). The view above includes most of the high peaks of the park, including the highest (Mt. Lyell). The diagram below, courtesy of CalTopo, provides the names of the peaks seen in the photo above.

Analysis courtesy of CalTopo
Amazingly enough, Half Dome, Sentinel Dome, and El Capitan in Yosemite Valley are also visible! It's true that you cannot see very much of these iconic rocks, but their summits peek out above the intervening ridges. One generally needs binoculars or a powerful zoom to spy them. 

Still not obvious? I've outlined the top of Half Dome below, with the ridge of El Capitan below and slightly right. There is a much better view to be had of Half Dome from about 5 miles south of the trail near the junction of Keyes Road and S. Hickman Road. It's been a bit of fun arguing over the years with people who are absolutely sure that Half Dome can't be seen from the valley for all kinds of logical reasons (the photos of course are photoshopped or whatever, which by the way is not a skill that I have).

In any case, the view was one of the best gifts of this beautiful day. I hope your Christmas and other celebrations were wonderful, and that you have a great new year! Thanks for reading!