Sunday, May 4, 2014

El Niño Beginning to Reach Surface

It looks like the much-anticipated El Nino is currently reaching the surface in the eastern Pacific.

Latest sea surface temperature anomalies (SSTAs) over the globe show our El Nino beginning to blossom in the sporadic areas in the waters west of Ecuador. This has been a long time coming, as we have been discussing extensively the Kelvin Wave that has been producing record-breaking temperature anomalies, as high as 6 to 7 degrees C above normal! The wave has been slow to push northward due to a not-as-favorable environment above the surface, but now that we are seeing the El Nino evolve, it can be expected that we will be in at least moderate El Nino territory by the time we hit late autumn.

Mean water temperatures along the equator from the surface to 500 meters down (top),
and anomalies for the same cross-section region (bottom).
If we take a look at sea surface temperature anomalies, now diagnosed on a cross-section along the equator from the surface to 500 meters down, it is evident that this Kelvin Wave-produced warm water is quickly upwelling to the surface. We see anomalies as high as 6 degrees C above normal about fifty meters below the surface, as is seen on the bottom panel in the top-right corner. As this body of warm water continues to push to the surface, we will likely see gradual weakening of these anomalies, but they should still be strong enough to propel us into our first El Nino event in multiple years.