Meteorology Measurements
Tower #1 Location…
The historic Sagehen manual weather station–NOAA National Weather Service Cooperative Observer Program (NOAA NWS COOP)–was established in 1950 in the lower camp just west of the tool shed.
In 1993, Faculty Director Reg Barrett obtained a National Science Foundation FSML grant, and the station received its first automated met station, which was co-located next to the NOAA NWS COOP station (Tower 1 v.1).
Speaking to Shorty Boucher, who was the station manager when the Tower 1 v.1 automated station was first installed, they worked with Hal Klieforth at DRI from the beginning of Tower 1 v.1 in 1993, to when she left in 1995.
Hal would deal with the data from both the manual NOAA NWS COOP observations, and the new automated Tower 1 v.1. I suggest that in 1997, Klieforth got WRCC to automate the data ingestion, which is where the continuous WRCC data record appears to begin for Sagehen. Somewhere at WRCC, Klieforth’s automated data record from 1993-1997 is hiding.
Over the years, this location grew over with evergreen trees, rendering it less accurate as a weather data collection and atmospheric monitoring site.
In the fall of 2001, several new monitoring projects began at Sagehen, including:
- Precipitation ground-truthing of cloud-seeding and Dopler radar projects with a Geonor gauge installed by Arlen Huggins of DRI;
- The installation of a National Atmospheric Deposition Program (NADP) site, and
- A new Tower 1 and additional hydrological instrumentation by Doug Boyle of DRI.
In conjunction with these projects, we relocated the weather station to the more open and spacious East Meadow, approximately 200 yards east of the old site (39°25.893′ N 120°14.393′ W; elevation: 6335 feet).
There is one year of overlapping comparison data for the sites.
Precipitation Gauging
The historic precipitation gauge in the East Meadow was an unreliable tilt-bucket type. For more accurate data, Sagehen also collected and contributed manual precipitation readings to the NOAA National Weather Service Cooperative Station Observations program (NOAA NWS COOP).
To provide ground-truthing for cloud seeding operations and regional Doppler radar readings, Arlen Huggins of DRI installed a GEONOR precipitation gauge at Sagehen next to the Tower 1 v.1 weather station. In order to get overlapping data, we recorded precipitation from both gauges starting in the fall of 2001 (when the GEONOR was first installed) until October 29, 2002. We also collected NOAA NWS COOP manual precip for the overlap period and found that the GEONOR was right on. Jeff actually felt that it was probably a bit more accurate than his manual measurements, even though he was quite careful.
On that date, we removed our crappy old tilt-bucket gauge and made the GEONOR our only precip. We also moved the gauge to a more open area in the meadow near the NADP site. For the indicated period of time, the GEONOR was recorded as “#2 rain gauge” and the old gauge continued to be “precip” in the WRCC data record. From 10-29-02 to the present, the “precip” record is from the GEONOR.
If you need the complete data record for the GEONOR, try hunting around the records for the “#2 rain gauge” data. If you have trouble finding it or need older, archived data, contact Arlen Huggins at DRI: huggins@dri.edu (or Greg McCurdy).
Other Weather Data Sources
Sagehen’s remote weather data sources in the Sagehen Creek and Independence basins continue to expand, starting with four additional towers with basic weather monitoring and ground moisture sensing installed temporarily in 2002 and permanently in 2003. Three 100′ towers came in 2008.
This early expanded data is spotty. Despite assistance from Kevin Browne and Marchall Minobe at UCNRS, we had immense trouble keeping the network running and–when it didn’t–figuring out where problems lay along the data collection and communications chain. We eventually resolved some of these issues around early 2009 by re-siting some towers, upgrading the communications backbone hardware, increasing electrical production and storage, adding Meraki units for on-line status reporting, getting all dataloggers on automatic download via TCP/IP, and joining the Keck database along with Angelo Reserve. But lack of adequate oversight continued to be a problem.
During this period, Doug Boyle at DRI began dramatically increasing his investment in the basin, funding Brad Lyles to provide technnical support, adding entire towers and, at existing sites, enhancing instrumentation: soil chemistry, snow pillows, precipitation gauges, etc. There is more metadata about individual towers and instruments in the Keck database.
As of spring 2010, there were 10 networked Sagehen met towers in the basin, as well as communications towers and other collection sites like an NRCS SNOTEL site at the top of the basin ridgeline, and another on the shore of Independence Lake in the next basin over. We also continue to add stream and weather data collection in the North Fork of the American. See our Resources page for more detailed information and related data sets like groundwater height and temperature, stream flow and chemistry, etc. The Sagehen News blog also contains information about this ongoing process.
Sagehen sites are located along east-west and north-south altitude transects. Use our Google Map for precise current locations and any recent additions.
Forestry
Sagehen implemented significant forest thinning and mastication upstream of the USGS stream gauge from 1 June to 1 September 2016, and sawlog removal from 20 October, 2017 through snowfall, and again in the early summer. Presumably, there are, or may be, effects on wildlife populations, forest metrics, meteorology, stream and groundwater hydrology that should be considered. Sagehen is conducting camera trap and other monitoring to assess some of these effects.
The Spring Chicken project created a fuel break along the Forest Service 11 road to the Sagehen Campground over multiple years from the late 1990’s to the early 2000’s.
More information about Sagehen forestry and fire history available from the Tahoe National Forest.