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Outgoing Longwave Radiation (OLR)

Outgoing Longwave Radiation (OLR) data at the top of the atmosphere are observed from the Advanced Very High Resolution Radiometer (AVHRR) instrument aboard the NOAA polar orbiting spacecraft. Data are centered across equatorial areas from 160°E to 160°W longitude. The raw data are converted into a standardized anomaly index. Negative (Positive) OLR are indicative of enhanced (suppressed) convection and hence more (less) cloud coverage typical of El Niño (La Niña) episodes. More (Less) convective activity in the central and eastern equatorial Pacific implies higher (lower), colder (warmer) cloud tops, which emit much less (more) infrared radiation into space. More information can be found at the Climate Prediction Center OLR page.

Outgoing Longwave Radiation (OLR) Last 12 Months (W/m2)
Apr 2013May 2013Jun 2013Jul 2013Aug 2013Sep 2013Oct 2013Nov 2013Dec 2013Jan 2014Feb 2014Mar 2014
+0.6
+0.6
+0.4
+0.7
+0.9
+0.4
+0.2
+0.8
+0.9
+0.4
+0.2
-1.1