During the week of end of July 2005 there has been a notable increase in the amount of missing OLR data from NOAA-16 satellite. These data serve as primary means for determining convective anomalies in the tropics and subtropics, and are used extensively for monitoring the MJO, easterly waves in the Atlantic, ENSO, etc.

The problem with the NOAA-16 OLR data is the increase in the amount of missing data for the orbits that occur in the early morning hours (night passes).  However, there are no known problems with the integrity of the data that are collected, i.e. calibration , etc. appear to be fine.  Polar-orbiting data  are only available twice per day over any given portion of the tropics. The data for the two passes (day and night) are usually averaged together to minimize the effect of the strong diurnal cycle that is typical in the tropics. The increase in missing data for the nighttime passes on NOAA-16 has resulted in missing daily averages for many areas since late July.  Users of climate monitoring and application should exert caution in using the NOAA-16 OLR data.