A high contrast study of the twists and turns of the disintegrating bole of a lodgepole pine on the slopes of Charlton Peak.

From the 26 mile San Gorgonio High Line trail run a couple of weeks ago.

From a run at Ahmanson Ranch earlier this week.

Also from Sunday's run on the Backbone Trail in the Santa Monica Mountains.

The windward side of this foxtail pine snag has been blasted by the icy winds of a multitude of Winter storms. The wind has sculpted the mineral-like wood, exposing and accentuating its inner layers.

The photo is from last Saturday's Cottonwood Pass - New Army Pass trail run. Nearly all of this route is above 10,000 ft. and 12 miles of it are above 11,000 ft. This relatively dry, high altitude habitat is home to the southern foxtail pine (Pinus balfouriana subsp. austrina).

One of the less common Sierra conifers, the tree is a long-lived species that is closely related to the bristlecone pine. The FEIS database references a southern foxtail pine 3400 years old, and the Gymnosperm Database a specimen with a crossdated age of 2110 years.

Because the tree grows so slowly, the wood is dense, and dead trees are slow to decay. In the vicinity of Cirque Peak, and a few other areas, dead foxtail pines and remnants are found above the current tree line. By crossdating tree ring sequences, a study published in 1997 found that over the past 3500 years the tree line in this part of the Sierra has generally been higher than it is now.

The study deduced that one period of reduced tree abundance and lowered tree line elevation was associated with warmer temperatures, and at least two severe multi-decade droughts. In contrast, the most recent decline has occurred during a cold, wet period that started about 450 BP.

It is remarkable that some of the dead foxtail pines studied here were alive during the Bronze Age, 4000 years BP.

As found on Sunday's run at Sage Ranch Park.

From Sunday's hike/run up and down Mt. Baldy's South Ridge.

Study of a mushroom-like arrangement of newly sprouted Big Leaf Maple Leaves. From Sunday's Red Box - Bear Canyon trail run.

Study of color, form, and texture in decomposing wood. From Sunday's Red Box - Bear Canyon trail run.

Macro still life of Douglas' nightshade at Stoney Point, a bouldering and top-rope climbing area in Chatsworth, California, northwest of Los Angeles.

From Sunday's run of the Will Rogers - Temescal loop.

Related posts: Spring on the Bent Arrow Trail, Will Rogers - Temescal Loop

From a run to Calabasas Peak on the Secret Trail in February.

Related post: Secret Trail to Calabasas Peak

Green beneath Summer's bleached stalks, the growth of this grass at Sage Ranch reflects the near normal rain season we've had to date in the Los Angeles area, and over much of Southern California. Since the start of the water year on July 1, Downtown Los Angeles (USC) has recorded 4.66 inches of rain. When this photograph was taken, January 11th, 4.66 inches was almost exactly normal rainfall for the date.

However, as is so often the case in Southern California, this apparent normality is the sum of offsetting wet and dry periods. December's precipitation was generally well above normal, but January has been dry, dry, dry. Today, the Los Angeles rainfall total is about 0.5 inch below normal, and every day it doesn't rain, our deficit increases by about 0.10 inch.

So when might it rain? A very strong 200 kt Pacific jet stream has pushed up a high pressure ridge over the West Coast, blocking storms and warming temperatures. Big upper level ridges such as this are consistent with La Nina, and have been a recurring theme this Fall and Winter. Much of our rainfall and cold weather this season has occurred when an extended Pacific jet collapses or contracts, and a blocking ridge shifts west, opening the door to cold storms plunging down the backside of the ridge from the north.

Over the next 1-2 weeks, this is expected to happen again, but this time there is a wildcard in the mix. One of the reasons the Pacific jet is so strong is the active phase of the Madden-Julian Oscillation (MJO) is present in the Western Pacific. As described in this Climate Prediction Center document, this scenario sometimes leads to a heavy West Coast precipitation event.

It's too far out for the medium range models to be of much help in assessing the likelihood of such an event developing. At the moment, about the only thing that can be said with some certainty is that a pattern change is in the works, and by the end of January there is a chance of some rain in California and the West. We'll see!

Related post: Southern California 2008-2009 Winter Precipitation Outlook, Snow on Oat Mountain