D-1 (3743 m) climate station: CR21X data.

Climatological data were collected from a Niwot Ridge climate station (D-1) throughout the year using a Campbell Instruments CR21X data logger. Maximum and minimum values are recorded instantaneously, with the sampling interval being 30 seconds. Daily means and totals are calculated from 2880 individual measurements. This instrument was programmed to generate both hourly and daily output. Parameters measured include solar radiation, air temperature, relative humidity, barometric pressure, wind speed, wind vector, and wind direction. Solar radiation CR21X measurements were discontinued 10 August 1993.