Hubbard Brook Experimental Forest (USDA Forest Service): Daily Solar Radiation Measurements, 1959 - present

Daily solar radiation has been measured at Hubbard
Brook Experimental Forest Headquarters since 1959, using
several different sensors. Radiation was recorded
continuously first by a Belfort pyranograph and later by a
Weather Measure pyranograph. The pyranograph has been at its
current Headquarter location since 1960 and before that at
weather station 1, near weir 1. With the installation of the
automatic weather station in 1981, a LiCor pyranometer was
collocated with the pyranograph and used as the primary
radiation sensor. The pyranograph operated until 2000 as a
back up. Solar radiation is now sampled by the LiCor sensor
once per minute and hourly and daily means are calculated by
a Campbell CR-21 Data logger and reported in Mj/m2. These data were gathered as part of the Hubbard Brook
Ecosystem Study (HBES). The HBES is a collaborative effort at
the Hubbard Brook Experimental Forest, which is operated and
maintained by the USDA Forest Service, Northern Research
Station.