| Description: | On several occasions in early 1999, large (10 percent) differences between the global PSPs
and the NIP were observed. In each case, the NIP reported low relative to the direct
flux reported by the PSPs. These occurrences persisted for several days each time and were
likely due to salt on one or more of the radiometers.
There was a large discrepancy in the comparison of the PSPs and NIP during December (5-10
percent). This discrepancy got worse through the month and then suddenly improved after
a rain event on December 23. There was likely salt deposited on the radiometer windows
that was washed off in the rain.
The observer daily rounds were being modified to include more regular cleaning of
radiometers to address this issue. |