Friday, May 21, 2010

The animation illustrates the evolution of sea surface temperature (SST) and sea surface height (SSH) anomalies* (relative to the respective normal state, i.e., seasonal climatology) associated with the 2009-10 El Nino in the Pacific Ocean.  SST and SSH anomalies reflect the heat content in the mixed layer (approximately upper 50 m) and the upper ocean (approximately upper 150 m) respectively. They provide complimentary views of the oceanic signature of climate variability El Nino. In April 2009, initial warming appeared in the eastern equatorial Pacific and grew into a moderate warming event by the end of the year. The event decays somewhat during the first two months of 2010, but later strengthens so that it now ranks in the top ten of the strongest events observed to date.  The latest data shows the surface warming extending farther westward across the dateline than was seen in most of the El Nino events in the past few decades.

*Data: The SST data are obtained from a blended AMSR-E and MODIS  product.  The seasonal climatology of SST (derived from AVHRR Pathfinder SST for the period of 1982-2008) is subtracted from the AMSR-E and MODIS blended data to produce the anomaly. The SSH data are from the OSTM/JASON-2 satellite altimetry mission. The seasonal climatology of the SSH data is for the period of 1993-2008.