NIM/SKYRAD/M1 - Unknown problem with PIR1
|DataStreams:||nimskyrad60sM1.b1, nimskyrad20sM1.a0, nimskyradM1.00|
Spikes in Shaded 1 occur frequently during this time period, resulting in differences b/t shaded1 and shaded2 exceeding 20W/m2. Instrument connections were checked and a spare PIR instrument was tried in the place of PIR1 (shaded1). After returning the original PIR1 to its original location data again looked good and very close to PIR2. Problem appears resolved but exact cure is unknown.
Fortunately the downwelling longwave hemispheric irradiance for this station has redundant instruments, PIR1 (aka shaded1) and PIR2 (aka shaded2). Disregard PIR1 data and use only PIR2 during this time range.