SSCZO - Southern Sierra Tour 2014
Granite Lake, seen from the Gaylor Peak ridge.
Gaylor Lake and the Yosemite National Park high country
View of Mt Dana from Gaylor Peak.
A meadow near the GLORIA and SNOTEL sites, on the agenda for Day 1.
Patterned ground caused by frost heaving near Silverpine Lake, seen from one of the hikes.
Tufa towers line the shallow waters of Mono Lake.
Mono Lake provides habitat for many species.
The Sierra Nevada crest above the Mono Basin
On Day 3, the Tour will stop by San Joaquin Experimental Range, in the oak-pine woodlands of the foothills (about 400 m in elevation).
Day 3 will conclude with stops in the Providence Catchment, including a stop by the P301 eddy covariance flux tower.
Other points of interest in the Providence Catchment include the P301 meadows, which has piezometers, wells, a mini met station, and the distributed wireless sensor network for water balance measurements.
Check out several sites from the planned Southern Sierra Tour, a field trip following Mountain Observatories: A Global Fair and Workshop on Social-Ecological Systems.
You can see more photos from the sites along the trips in the full album here.
SSCZO - Flux Towers
At the San Joaquin Experimental Range (SJER), the SSCZO flux tower sits on a small rise in the oak-pine woodland. This is the lowest site of the flux-tower transect, with the tower installed at 405 m in elevation.
Fully erected, the SJER tower stands about 29 m tall (~95 ft).
However, the tower also telescopes down for maintenance.
Erin Stacy (UC Merced) exchanges the filters on the gas intake.
The flux tower at Soaproot Saddle stands in a small forest clearing. The tower, approximately 39 m tall (125-130 ft), is surrounded by a mix of Ponderosa pine and oak. Here the WyCEHG (Wyoming) sets out equipment to conduct geophysical surveys in the tower footprint.
Defensive measures were taken for the Soaproot Saddle tower in advance of a prescribed burn. The Clarence Burn burned up to a nearby firebreak in January 2014, but did not burn the area immediately around the tower
Matt Meadows (Field Manager, UC Merced) begins the climb for routine tower maintenance in a late January storm, 2014.
Pete Hartsough (collaborator, UC Davis) stands next to the Soaproot tower, September 2013, with core tubes in hand. A large drilling unit cored soil and saprolite to a depth of ~4 m on most attempts at this site.
The P301 tower is the tallest of the four towers at 50 m (160 ft), plus a lightning rod. It stands near the top of the Providence catchments at 2015 m in elevation.
The P301 tower near the end of the 2014 winter.
Matt Meadows (Field Manager, UC Merced) shows off the filter intakes at the top of the P301 tower.
An eddy covariance flux tower is located near the top of the P301 watershed. Instruments collect data on temperature, relative humidity, and fluxes of carbon dioxide and water vapor to determine the physiological responses of the site (for example, how photosynthesis increases with light) and summed over a year to determine the carbon balance of a site (how much carbon it is gaining or losing). Three other flux towers have been instrumented at different elevations with the Sierras including the San Joaquin River, Soaproot, and Short Hair Creek.
This west-east transect spans elevation gradient from 400 m to 2700 m. The change in elevation is accompanied by a slight increase in precipitation, but the main change is a shift from rain-dominated precipitation to snow-dominated precipitation. The climatic shift plays out in other ways as well. At lower elevations, high temperatures and low water availability limit evapotranspiration by vegetation. Meanwhile, forest activity (evapotranspiration) at higher elevations is limited by cold winter temperatures. There is a sweet spot at middle elevations of yera-round evapotranspiration and forest activity.
Photo galleries of each flux tower are available: San Joaquin Experimental Range; Soaproot Saddle; Providence subcatchment P301; and Short Hair Creek.
SSCZO - SJER field area
The SJER tower is situated on a small rise in the north part of the Experimental Range property. The tower is at approximately 405 m in elevation in a landscape of oak and pine woodlands.
With the rains of the past few weeks, the grass around the tower has greened up. Still, 2013-2014 has been a very dry and warm winter.
The SJER tower stands roughly 28 meters tall.
Filters on the air sampling lines at SJER are replaced every month to few months.
A heavy-duty box at the foot of the tower houses the data logger, IRGA, and other electronics.
The vegetation is dominated by oak (Quercus kelloggii) and foothill pine (Pinus sabiniana).
A warm morning at the Range, February 2014.
The SJER office is along the main road, past the turnoff to the tower.
Affordable accommodations are available at the SJER through the U.S. Forest Service.
A meteorlogical station stands near the office and guesthouse buildings.
The landscape was very dry in September 2013.
University of Wyoming researchers visited SJER in September 2013 to conduct geophysical surveys of the subsurface.
This gallery showcases the landscape, vegetation, equipment and facilities at the SJER field area.