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Install Weather Station at Henness Ridge

Yosemite National Park » Install Weather Station at Henness Ridge » Document List

This project is being proposed by researchers Douglas Alden and Carolyn Ellis at Scripps Institute of Oceanography. This project is part of their research on how Atmospheric Rivers form, evolve, and then impact conditions over California. Research efforts will focus on further improving situational awareness of ARs and the associated precipitation to enhance the resilience of California

The project involves installation of a surface meteorological station, data acquisition system, and disdrometer at the NatureBridge Campus at Henness Ridge. These installations would be accompanied by an enclosure that houses a rugged computer, uninterruptible power supply (ups), and data telemetry system. The disdrometer is able to measure the properties of falling precipitation and therefore differentiate between different forms of hydrometeors (rain, snow, hail, etc.). The weather station and disdrometer would be installed at an elevation of interest for determining when in the winter season and during which events rain transitions to snow.

The surface met and data acquisition system would be installed on a pole. The disdrometer would be installed on a separate pole or free standing base. Ground disturbance could range from minimal (~18 in stakes into the ground to secure tripod/instrument feet) to slightly more aggressive (~3-4 ft deep x ~1 ft wide holes to secure instrumentation pole w/concrete base). A combination of these methods could be used. Additional ground disturbance would be required to trench a 2" power/data conduit as 120V AC (3 Amp) power is required for the station.

These instruments would be installed at the NatureBridge Campus at Henness Ridge. Three alternative site locations are currently being considered. These are (not in order of preference):

Option A: 37.64720, -119.70380
Option B: 37.647085, -119.70362
Option C: 37.64730,-119.70430

Shallow trenching (~8 inch depth) would occur from these locations to the nearest building, a distance of approximately 30ft at each location. The areas that would be trenched have already experienced ground disturbance.

Installation would require a team of 2-3 approximately two days to complete and would require maintenance and calibrations once or twice a year for the duration of the project.

The weather station with disdrometer would remain in place for up to 5 years. Thereafter, it would require additional compliance review and approval to remain.