NCDC's Climate Data Records Program has just released a new Daily OLR dataset that may supersede the Interpolated OLR from NOAA/ESRL that many of us use. The new dataset was developed by Hai-Tien Lee at the University of Maryland.
The NCDC dataset uses the HIRS sensor, whereas the ESRL version used AVHRR. Both sensors are aboard the NOAA polar orbiters. The main practical difference is that HIRS is more sensitive to water vapor, which provides additional information in cloud-free regions.
A few other key differences:
The NCDC dataset also uses geostationary estimates of OLR
The inclusion of geostationary data eliminates aliasing from the orbital precession of the polar-orbiters. For example, the spurious signal in the Wheeler-Kiladis spectra is gone in the new dataset (see attached).
The new dataset has been calibrated for changes between satellites, making for a more homogenous time series.
1.0-degree horizontal resolution instead of 2.5 in the ESRL data
The ESRL data has some minor geolocation errors in recent years that are not present in the NCDC version
The new dataset is currently available for 1979 - 2012. It does have some missing days, mostly in 1985. Sometime this fall we're hoping to have an interim version that updates in near real time.