Infilled daily air temperature data for C1 chart recorder, 1952 - ongoing.

Daily minimum and maximum surface air temperature data have been
collected at the C1 climate station (3022 m asl) almost continuously
from 1952 to the present. C1 is on locally level terrain on the
southeastern flank of Niwot Ridge, 9.7 km east of the Continental
Divide. Surrounding vegetation is generally closed-canopy subalpine
conifer forest. Temperature minima and maxima were measured with a
chart-recording hygrothermograph housed in a Stevenson screen
located in an open, sparsely treed area adjacent to the forest
proper. Hygrothermograph records were calibrated at the time of
chart changes against liquid-in-glass thermometers. Processing
included quality checks and infilling of missing daily data (see
Methods).