Beginning with October 2001 data, the source of OLR data was changed from NOAA-14 to NOAA-16.  The reason for this switch is that the scan motor on the AVHRR instrument aboard NOAA-14  is tempermental and is causing much missing data.

Note that the time of observation at the equator as of late October 2001 was:

	NOAA-14  0532/1752 local time

	NOAA-16  0151/1351 local time

We have noticed over the past several months an increase in negative anomalies over continental regions, particularly desert regions, that are due to the drift in observing time of NOAA-14.  These "anomalies" are gone when NOAA-16 data are used, because the present observing time of NOAA-16 is near the bulk of observing times that makes up the 1979-1995 climatology.