The human warming-riled monster weather event that is El Nino continued to advance over the Equatorial Pacific this week. Ocean surface temperatures throughout the basin from north and east of New Guinea and along a broad stretch of thousands of miles of ocean climbed. Sporadic west winds and an overall weakness in the trades extended the expansion of warm surface waters along the serpentine back of the El Nino pattern from west-to-east even as a high heat content Kelvin Wave kept conditions below surface much warmer than normal.
(Pacific Ocean sea surface temperature anomalies from 2 April to 28 May. Animation source: NOAA)
Large and growing regions of 1 to 2 C warmer than normal surface temperatures expanded in broad, 1,000 + mile stretches near the date line and ranged out from the west coast of South America. An impressive region of, very hot, 2-3 C positive anomalies grew through an ever-larger span from Santa Cruz Island to coastal Ecuador and Peru. Though the above graphic is not granular enough to catch it, daily anomalies in this hot pool exceeded extremely intense +3.5 to +4 C readings.
Readings in the range of +0.5 to +1 C invaded regions north to south, east to west, joining in an extraordinary zone stretching from the Philippines to South America, and from Baja to Hawaii to the Solomon Islands. A separate pool of very hot water north of New Guinea and near the Philippines is likely to play a further role in El Nino development throughout this year should weak trades and anomalous west winds persist. Then, a second and reinforcing pulse of warm water is predicted to push the entire Equatorial Pacific Basin well above a +1 C positive anomaly by late Summer through Fall.
(Sea surface temperature anomalies in the four key Nino regions all show continued warming through the end of May. Image source: NOAA.)
The tightening grip of El Nino is plainly visible with each of the four key Nino zones showing ongoing temperature increases in what is now a 3-4 month long event. Meanwhile, the key Nino 3.4 zone closed its 4th straight period above the +0.5 C Nino threshold even as it jumped to +0.6 C above average this week. Notably, the Nino 1+2 zone off South America hit a very warm +1.6 C average positive anomaly this week, showing additional warming from strong late April values.
Together, these values all show very solid continued progress toward El Nino.
(Map of geographical Niño zones provided by NOAA.)
Conditions in Context: May 2014 Likely Hottest on Record Amidst Ongoing Extreme Weather
Overall, Equatorial Pacific ocean surface temperatures continued their advancement from May 27 to June 2, rising from +0.59 to +0.68 C above the 1979 to 2000 average throughout the week. Global sea surface temperatures have remained in an exceptionally hot and likely global record range between +1 and +1.25 C above 1979 to 2000 averages throughout the month of May and into early June. These extraordinary readings likely combined with very high atmospheric values to put May of 2014 in the range of hottest on record. It is worth noting that, according to NOAA, April of 2014 was also the hottest in the 134 years since global temperature measurements began.
El Nino tends to spike atmospheric heat and, when combined with a brutal human greenhouse gas forcing, greatly increases the likelihood that a given year will reach new global heat extremes.
For 2014, El Nino and global warming related weather disruptions already appear to be taking hold with the Indian Monsoon appearing weak and delayed, a summer heat dome building over Europe and Western Russia, with Southeast China experiencing record floods even as northern and western China and Japan experience record heat. Ongoing droughts and crop disruptions in Brazil, building heat and drought in Indonesia, and Australia experiencing two back to back hottest years on record is also indicative of the screaming global heating that typically comes when El Nino gives human-caused warming an explosive boost.