Sunday, October 26, 2014

Autumn Adjustments

Bit of rain in the park last evening. Foliage color in the Valley is quite nice now, with parts of Southside Drive being a bright corridor of yellow maples. Even the dogwoods are as much yellow as pink. Wherever you find it, Dogbane outshines everything in pure canary yellow.

Vernal Fall trickles and at the normally lowest flow of the year, the Merced is running about 1/3 of average for this date. Lessingia blooms can still be found, some Madea still in blossom at Cascades, and there's at least one azalea flowering at Yosemite Lodge. Varied thrushes have appeared early and are relatively numerous. Bucks are at their biggest and in their most aggressive season; give them respectful space. Climbers are all over El Cap, Washington's Column, etc. in this cooler period.

The high country had a dusting of snow a few weeks ago, but real winter seems to be a good ways off. November is projected to be dry (and December in the Sierra doesn't look to be especially wet at this point).

Friday, July 18, 2014

Range of Lightning

A double-handful of wildland fires have been ignited by several days of monsoonal storm cells over our part of the Sierra. All of the starts are in remote areas and will be allowed to proceed as nature intends for now.

The mid-summer moisture has been locally intense: Tioga Road was closed for a time on Tuesday so that runoff debris could be removed, while a few miles away, no rain fell at all. The volume in the Tuolumne and Merced Rivers has jumped from the localized downpours. The gauge at Pohono Bridge in Yosemite Valley went from 15% of average flow to about 70% of average.

It was quite a surprise to find that Yosemite Falls had returned from the dead yesterday morning. Transient petrichor changes the feeling of our forests from that of dusty late August, to that of another mountain range altogether. This precipitation temporarily alleviates a sense of drought, but our mountains are still quite dry (and flammable).

Flowers look great at 7-9000' now: Senecio, lupine, Aster, Pentstemon, Epilobium, Delphinium and more are adding color to the quiet aridity.

There have been a few instances of oak branch drop in the past few weeks, wherein a healthy-seeming oak loses a large live branch suddenly. Watch the skies....

Thursday, May 1, 2014

Tioga Open All Year

Of course, Tioga Road is closed to vehicles through the winter, but visitors are using it all through the snowy season on skis and snowshoes. The high country isn't closed, it's just inaccessible to an invention that wasn't allowed into the park until 1913. The route opens to cars tomorrow, predictably early due to the unusually light snowpack. Here's what the Sierra high country looked like after fresh snow late last week.

Several of us witnessed a 2-minute avalanche of snow sluicing to the bottom of Tenaya Canyon from Clouds Rest yesterday.

While Yosemite Falls looks might hearty at the moment, the river is running below average again, and some observers believe that we've already passed peak runoff, several weeks early. Sentinel Creek is just now trickling as far as Southside Drive, and Ribbon Creek flows nicely to the river. Wosky Pond has a tiny bit of water in it. Eagle Creek and all channels of Indian Creek are dry at Valley level.

In the Valley, dogwoods are glorious right now, Senecio is in bloom already. Mule deer bucks have new antlers starting to grow. Snowplants have been up for weeks and are abundant in Mariposa Grove now.

Western Tanagers arrived in the Valley last week and are adding to the incessant soundtrack of spring. In addition to public birdwalks from the Yosemite Art Center 3 days a week, the Conservancy has a suite of truly terrific birding field seminars spread through the year; valuable for beginners or veterans.

The park is making big plans for celebrating the 150th anniversary of its federal protection on June 30; even Galen Clark is planning to attend. He'll be at LeConte Lodge to start their season of great presentations this Friday night.

Monday, April 14, 2014

Peak of Spring

The Merced River canyon below Yosemite Valley is ablaze with poppies and dozens of other flower species just now. The color of millions of petals is dazzling even from miles away on the Glacier Point Road. Clarkia is already in bloom in the very lowest foothills.

The Merced River itself is running just above average, peaking overnight at just under 1300 cfs at Pohono Bridge. It's been a startlingly mild winter and spring, but 1977's drought had the Merced at less than 300 cfs on this date. With a snowpack measured at one third of normal water content, high flows will not last until the typical annual peak in the 3rd week of May. I'd expect visitors may start to be disappointed by waterfall volume as of July. We did have light flows of frazil ice (better called 'wist ice') 2 weeks ago, but this hasn't been a year for this phenomenon.

The Glacier Point Road was opened to bicycles for the weekend and it was a terrific national park experience to pedal through fir forest full of birdsong, melting snowbanks, and other happy cyclists, with the safety of there being no motor vehicles on the road. Cars can now drive out to Glacier Point.

Snowplants have been emerging for about 3 weeks already. Miner's Lettuce and Gooseberry are blooming in Yosemite Valley. What we call 'the first dogwood' located along Hwy. 140 above Cascades is officially in bloom now; Valley trees will be lit up shortly. Orioles have been in the Valley since the end of March, with black-throated gray warblers right behind. Black-headed grosbeaks arrived in the Valley a week ago. Vireos and tanagers are on their way. Conservancy naturalists have started springtime birdwalks and botany walks from the Art Center and there are some really great natural history field seminars coming up.

Lunar eclipse tonight!

Thursday, January 23, 2014

Junuary?

Remarkable aridity and mild temperatures continue in the Sierra and California. Badger Pass (Badger Grass?) Ski Area is closed, the Valley Stables have opened. We've been in and out of Red Flag Warnings (fire danger) since late December. The Merced River has flatlined at around 20 cfs (at Pohono Bridge) whereas the average flow for late January is almost seven times that!

Incense cedar pollen is flying now, producing allergic responses in some locals and visitors. Indian Paintbrush was reported in bloom above El Portal but it's too dry for most flowers to emerge. There are only a couple waterfall buttercups blooming near Ned's Gulch where there were hundreds a year ago. Bears are still active in the Valley (as some can be every other winter in recent years); I saw one yesterday. Surprisingly a trace of snow is accumulating in the high country at this moment.

For Martin Luther King, Jr. weekend, I roamed the site of Camp A. E. Wood, where African-American troopers were stationed for the summers of 1899, 1903 and 1904. These Buffalo Soldiers patrolled Yosemite National Park from this base in Wawona. Among their many accomplishments was the 1904 establishment of what's believed to be the first formal interpretive facility in the entire national park system: the Yosemite Arboretum. Boundary changes the next year removed the Arboretum from Army stewardship and this promising start at educating and inspiring visitors was abandoned. Very faint remnants of the Buffalo Soldiers' interpretive work can still be discerned.

Here's another valuable interpretive effort from long ago: Yosemite Nature Notes, the precursor of this blog and of Steve's excellent video series. What creative efforts of ours will be abandoned or sustained for the next hundred years?

Monday, December 16, 2013

A Winter's Solstice

The extra cold that the West had last week, was surely felt in Yosemite. Snow fell well below the park boundary and still persists in the shady parts of El Portal. The Merced River has frozen over in much of the Valley and the southern cliffs are streaked with frozen waterfalls. We did not get enough snow to open the Badger Pass area to skiing, etc.

The Merced is running at less than 30% of normal volume, and the watershed still has a way to go to recover from two dry winters.

Yesterday's Christmas Bird Count featured a frosty cold morning then comfortable warmth in the afternoon (unless you were in the shadow of the south wall). Compiler Sarah Stock organized quite a large group of birders, and the birds responded. It's a good year for the colorful varied thrushes, a species that migrates here for the winter, though it doesn't come every year. Early efforts turned up quite a few owls, too: pygmy, screech and great-horned.

Solstice happens on Saturday, when the long, cold night dominates the Sierra. Have a closer look at Yosemite's winter on one of our snowshoe outings. Here's hoping for a snowy new year.

Monday, October 21, 2013

Shakin' It

The Clark Range, within the southeast corner of Yosemite National Park, has been seismically active in recent years. Many nearly imperceptible earthquakes occur here each year. There was a series of 4 shakers last night, some of which were noticed on the west side of Yosemite. The park community of El Portal sits astride the boundary of the granitic batholith and the older metamorphic belt. The way ores can concentrate near a contact like this, vibrations may, as well. Deep but slender barium mine excavations at the igneous/metamorphic boundary may serve as sound boxes where the resonances of the earth can surface.

When the Merced River is low, El Portal is a pretty quiet place, especially at night. Some of us heard at least some of the four 1.0-2.2 magnitude temblors as deep roars, lower pitched and shorter in duration than a passing jet. I noted the time of the clearest roar, at 2:54 a.m., and there it was on the USGS website, as a restless moment east of Gray Peak, and 15.9 km deep.

Aspen on the East Side and in small pockets within the park, are past their peak color, but still bright. In the Valley, the sugar maple has gone bare, but there's lots of color remaining.

Dogwoods are red,

The sky is blue.

The oaks are all golden,

And maples are, too.