NSA/SKYRAD/C1 - Discontinuity in Unshaded PIR data

There was a sudden increase in irradiance (from 140 to 190 W/m2) at 02/03/99 23:00.

• PIR1 minimum(pir1_min)
• PIR1 unshaded standard deviation(pir1_sd)
• PIR1 unshaded maximum(pir1_max)
• PIR1 mean(pir1_mean)