Outgoing Longwave Radiation (OLR): AVHRR
OLR (Outgoing Longwave Radiation) is a measure of the amount of energy emitted to space by earth's surface, oceans and atmosphere. As such, it is a critical component of the earth's radiation budget. In a different context, OLR values are often used as a proxy for convection in tropical and subtropical regions since cloud top temperatures (colder is higher) are an indicator of cloud height. OLR observations are made via the Advanced Very High Resolution Radiometer (AVHRR) instrument aboard the NOAA polar orbiting spacecraft. The raw ascending and descending swath data have been spatially and temporarally interpolated onto grids to facilitate use.
OLR estimates are a key component for the standard Madden-Julian Oscillation (MJO) CLIVAR diagnostics which are used to study the MJO and for climate model evaluation.
Long time series of up-to-date OLR values
High quality data access site
2.5x2.5 resolution may be too coarse for certain studies
NOAA Polar Orbiting Satelite series (AVHRR)