Crane Flat Lookout, Permanent Climate Monitoring Station Installation

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The purpose of this project is to install a high-quality permanent weather station that would be part of a national network of 250 similar stations. This station would be maintained and operated by the National Oceanic and Atmospheric Administration (NOAA) for a period of 50-100 years.

The weather station would consist of sensors placed on an instrument tower up to 10 feet above the surface of the ground, a battery/power supply box (4.5 feet high), and a Geonor Raingage (5 feet high)installed in an area 60 feet by 60 feet. A satellite transmission antenna would be mounted on the instrument tower and would not extend above the top of the tower. Each component would be anchored by concrete pads that will require excavation of holes of 1) 2 feet in diameter by 3 feet deep, 2) 3 feet in diamter by 5 feet deep, and 3) 2 feet in diameter by 3 feet feet deep. Installation of a shelter surrounding the raingauge would require up to eight holes for fence posts. Trenches 6 inches wide by 18 inches deep would be required to route conduit between the instruments and the AC power at the helibase (approximately 150 feet). Vegetation would be removed in the immediate area of each component and otherwise maintained as low cover as is the current practice.

Sensors would consist of three temperature sensors each enclosed in aspirated solar radiation shields, a cup anemometer (wind speed), a pyranometer (solar energy), and an infrared (IR) thermometer (ground surface temperature). A relative humidity sensor will be added upon completion of the evaluation period (one year). The Climate Reference Network(CRN) Parameters to be measured are: 1) Air temperature, 2) Precipitation, 3) Solar radiation (incoming solar energy at the surface of the earth), 4) Wind speed, 5) Ground surface temperature (IR), and 6) Relative humidity.
Precipitation data, recorded every fifteen minutes, and the other hourly observations will be collected and stored in a data logger attached to the tower. These data will be transmitted within a few minutes after each hour via a GOES satellite transmitter for further delivery to the National Climatic Data Center (NCDC), Asheville, NC. Summary of the Day (SOD) statistics will be computed operationally at the NCDC. The instrument system is designed with the capacity for future expansion to accommodate additional sensors, such as soil moisture, soil temperature, atmospheric pressure, and wind speed/direction at the standard 10-meter height. The design allows for future additions of sensors on the tower without disrupting the physical site.

There is an existing fire weather tower near the site. In order to minimize the instrumentation footprint, redundant instrumentation would be eliminated once the proposed station is running satisfactorily.