Best Little Hoarfrost

The recent weeks of steady cold allowed the growth of terrific hoarfrost formations in Yosemite Valley. Spikes and florets and feathers of ice condensed out of the atmosphere onto the ground, river ice, and tree branches wherever moisture and cold combined. A bit of this happens every winter, but this season's displays are exceptional.
Late this week, conditions have thawed. The first Amsinckia (fiddleneck) of the season has bloomed outside the Conservancy office in El Portal. There's a sunny bank where they often show early, and here's our first contestant in this year's mating game. Wilhelm Amsinck never came to California, but was a patron of the Hamburg Botanical Garden and his philanthropy is still rewarded today with us exclaiming his name each spring. (The picture shows fiddlenecks last spring.)

In shady spots further down canyon, Kumlienia (waterfall buttercup) is blooming profusely now. Thure Kumlien was a Swedish naturalist who relocated to Wisconsin a few years before the Muir family arrived there. As John Muir did, he spent as much time in the woods as he could and later taught school for a time. Now his legacy lives on in this genus, the first flower we find each season.

The road into Hetch Hetchy has been closed until an eroding section can be safely stablized.
Steve B. has crafted his best video yet, "One Day in Yosemite." After you watch it, plan yourself several days in Yosemite.
The Conservancy's 'Yosemite Outdoor Adventures' are all on line for the whole year now. Don't miss out on a chance to get out on the trail with us and learn from the best in the field.

No Ahwahneechee Apocalypse

For what we call 2013 the world continues on its way, no matter our contrivances. The Ahwahneechee did not predict a global apocalypse for this recent solstice, and they were right! Our physical cliffs endure and are not something that needs to be averted. In Yosemite, neither Half Dome nor Yosemite Falls noticed when we replaced old calendars with new ones. The one real change that occurred during our holiday scurryings was that the sun is starting to inch northward in where it rises and sets, and that each new day is a litle bit longer. To be more accurate, the sun isn't doing anything; it's our spot on the world that faces toward and away from the sun at a slightly different angle each day. Solstice is real to Yosemite, our calendars perhaps less so.
It's been quite cold in the park for a few weeks; there's snow and lots of ice in the Valley. Frozen waterfalls like Widow's Tears and Silver Strand (on the south wall, between Bridalveil and Tunnel View)are extra prominent and solid now. If you're thinking about a closer look, KC and JT tell me that Widow's Tears is the longest ice climb in the US.

Feathery worlds of surface hoar can be found in shady meadows early in the day. Small amounts of frazil ice have formed on some creeks. The snow cone at Upper Yosemite Falls is building steadily.
Badger Pass and Crane Flat both have healthy snowpacks for snowshoers and XC skiers. No one is ice skating on Tenaya Lake this winter.
Some of the Summer Triangle asterism is visible over eastern Valley walls before sunup. As Muir wrote it: 'each in its turn as the round earth rolls.'

Physical Cliff

Our physical cliff is a combination of higher pitches and reduced horizontality...
A couple of inches of snow came to Yosemite Valley Wednesday night and it's staying on the ground, at least in the shady areas.
The skies are meant to be off and on cloudy/wet the next few days. This could make for a damp Christmas Bird Count this weekend, the 16th, but the birds aren't going anywhere so we'll count whatever we see. Contact our compiler at sarah_stock@nps.gov if you're interested in participating in this grand citizen science project. Yosemite's count has been tops in the nation more than once in recent years, for numbers of white-headed woodpeckers and Williamson's sapsuckers. We have superb woodpecker habitat in our diverse forests.

Light quantities of frazil ice have been observed flowing in Yosemite Creek the past couple of mornings. Overnight mist-ice accumulations on the wall of Upper Yosemite Fall has led to loud booms by mid-morning as huge flakes peel off in the sunshine and start accreting into the snowcone.
XC skiing at Badger Pass opens this weekend, on 12 inches of new snow. The slopes need a bit more depth, still. We've had plenty of storms but the snowline has been high, almost as if the climate were changing...

December Rains

Recent storms have ended our Indian Summer conditions here. The snowline remained high, and it's quite mild this week, but Glacier Point and Tioga Roads are closed to cars (probably until May).
The Merced River shot up from around 60 to just over 2000 cfs in Yosemite Valley during the latest wave of heavy precipitation. Our waterfalls have roared back to life after a long parched spell.

Leaves are off the deciduous trees now. At the same time, El Portal has a lush ground cover of brand new grass and forb growth. Newly sprouted lupines and cranesbill are already identifiable by their foliage, but we don't expect flowers for a few months.
I spent Saturday pursuing nothing but woodpeckers; we encountered six species between El Portal, Foresta and Crane Flat - a couple more hours of daylight might've turned up more of this interesting taxa. Acorn woodpeckers are very busy storing and sorting this year's crop. Did you know that they're in the same genus as the Lewis Woodpecker? The genus name Melanerpes translates as 'black creeper.'
The Conservancy's 2013 field institute courses are all now open for registration; you can find birding, wildflowers, geology, photography, family programs, art courses, backpack treks and no less than seven trips to Half Dome in the "Yosemite Outdoor Adventures" line-up. Yosemite has something to teach you...

Peak leaf-peeping weeks

-Foliage in Yosemite Valley is at its peak color now. While weekdays are very quiet, recent weekends have brought in lots of leaf-peeping visitors. Black oaks, big-leaf maples, and black cottonwoods are all shining in their various yellows. Dogwoods own the red/pink. The sugar maple is bare.
-Michael Frye reported seeing azaleas blooming in El Capitan Meadow, and sure enough, I found them yesterday. On many of these yellowed shrubs are fresh, bright white flowers. The fragrance isn't strong, but a sniff puts one right into the warm days of June.

-In the canyon below Yosemite Valley, there are miles of grapevine - invisible all summer - now declaring its presence with yellow leaves. It's truly remarkable how abundant wild grape is, now that it's highlighted.

-The Merced River is still running quite low, at about 60% of average volume. The storm that's arrived today is not expected to add much precipitation, though we should see a bit of snow at low elevations. We'll probably lose some of our colorful leaves, but that just makes walking through the fallen foliage more fun.
-Our final field seminar of the year is on December 1: "The Day of the Woodpecker." You'd be astounded what there is to know about Yosemite's diverse group of woodpeckers.
-We start 2013 programs with snowshoe treks, and two special photography courses. All leaves remaining through the winter will be green; come see.

Click or Treat

It's a great time for photography in Yosemite. Though the sugar maple has gone bare, the big-leaf maples, dogwood and dogbane are really bright now, if you're in the right places. Oaks and cottonwoods are waiting their turn in the Valley. The Crane Flat and Hetch Hetchy areas are really colorful now.
-Photographers Keith Walklet and Mike Osborne still have a few spaces in their November 1-4 field program with Yosemite Conservancy. They are a remarkable team with a lot of Yosemite accomplishments to their credit.

-Two dark bears were seen for several days eating acorns high in a valley oak by the railroad engine in El Portal. In Yosemite Valley, they've also been harvesting directly from the canopy. With bathing suit season over, the bears are trying to take in 20-30,000 calories/day so they'll have a comfortable winter's sleep.
-Winter birds have arrived: juncoes, white-crowned and golden-crowned sparrows have descended to find seeds in snow-free El Portal for the winter. Varied thrushes have been seen in the Valley and near Merced Grove already. Naturalist Dan W. reports a meadowlark in Ahwahnee Meadow from earlier this week, when he was leading a "Yosemite Insider Experience" group for the Conservancy.
-We had another mild storm come through Monday, closing Glacier Point and Tioga Road with a few inches of snow. They're both likely to re-open shortly. The precipitation finally initiated the river's seasonal rise, from the year's low of 18 up to 26 cfs. Normal would be in the low 30's.
-I had a chance to examine one of the hand-hewn wooden stakes that John Muir used 1872 for the first quantitative glacier study in the U.S. It was found by NPS personnel on the 1936 glacier survey and brought to the park's museum archive. It was pretty interesting to handle something that Muir himself made when he was up at our glaciers with Galen Clark and Joseph LeConte. Regretably, Muir didn't bring his digital camera on those two trips...

Insatiable albedo

It's autumn and in Yosemite Valley:
-days are shorter
-the cliffs and trees cast longer shadows
-the sun is at a lower angle so it lights less ground
But we also find that:
-the lower sun lights the north wall more directly
-the pale, dry grass gives off a brightness not seen in summer's dark green
-the yellow of maples, milkweed, dogbane, raspberry and some oaks and cottonwoods add increased reflectivity to the substrate, from leaves both on plants and that have fallen on the dark ground.

This 'yellow day of October' bears out Muir's notion that the Sierra may actually be composed of light. It's nice to contemplate the conflation of matter and the electromagnetic spectrum while beholding the reflected glow with your own eyes here in Yosemite.

-In the Valley last week Conservancy naturalist MRoss observed both a gray catbird and the Asiatic form of an American Pipit.
-The one sugar maple in Old Yosemite Village is bright red-orange now.
-We are getting our first dusting of snow in the high country, with Tioga Pass being closed briefly.
-The Merced River flow at Pohono Bridge has flatlined at a thin 19 cfs. The historical average river volume for today is 30 cfs and rising.
-Geologist GStock's latest glacier observations indicate a rate of motion for the Maclure Glacier that is identical to what Muir measured 140 years ago. Sadly, though it's bigger than the Maclure, the Lyell Glacier appears to be in a terminal phase.
-That's Venus you see, really bright in the eastern sky in the morning. The nearby star is Regulus, the brightest star of Leo. What can we interpret from the apparent proximity of the goddess of love and the king of the beasts? Only our own spatial provincialism; Regulus is not close but is 77 light-years away from Venus. Regardless, the light of both bodies adds to the shine of not just Yosemite, but our whole bright world.