Saturday, 24 May 2014

The growing el-Nino

Global Sea Surface Temperatures Increase to Extraordinary +1.25 C Anomaly as El Nino Tightens Grip on Pacific

22 May, 2014
On May 22nd, 2014, global sea surface temperature anomalies spiked to an amazing +1.25 degrees Celsius above the, already warmer than normal, 1979 to 2000 average. This departure is about 1.7 degrees C above 1880 levels — an extraordinary reading that signals the world may well be entering a rapid warming phase.
SST anomaly May 22
(Global Sea Surface Temperature Anomalies per GFS Model on May 22, 2014. Image source: University of Maine.)
It is very rare that land or ocean surface temperatures spike to values above a +1 C anomaly in NOAA’s Global Forecast System model summary. Historically, both measures have slowly risen to about +.35 C above the 1979 to 2000 average and about +.8 C above 1880s values (land +1 C, ocean +.6 C). But since late April, sea surface temperatures have remained in a range of +1 C above 1979 to 2000 values — likely contributing to NOAA and NASA’s temperature indexes hitting first and second hottest in the climate record for the month. During May, ocean surface heating entrenched and expanded, progressing to a new high of +1.17 C last week. As of this week, values had exceeded +1.2 C and then rocketed on to a new extreme of +1.25 C (See Deep Ocean Warming is Coming Back to Haunt Us).
Should such trends continue, and with little more than a week left for this month, May of 2014 is likely to set a new record for global surface temperatures. And with El Nino continuing to tighten its grip on the Pacific, potentials for new all-time record high global temperatures for 2014 keep increasing.
(NOAA’s Climate Prediction Center found that April of 2014 tied April of 2010 as the hottest in the climate record. During this month, very few regions showed cooler than average conditions for the month while broad swaths of the globe were covered in warmer than average or record warmest temperatures. It is worth noting that 2010 was also an El Nino year. Image source: NCDC.)
Regions currently showing much warmer than normal sea surface temperatures include a broad swath of extreme +1 to +4 C readings from Baja California northwest toward the Bering Sea, an expansive zone of +1 to +3 C readings from the coast of southern South America and across the Pacific Ocean to New Zealand and Australia, almost the entire far South Atlantic between the East Coast of South America and the West Coast of Africa with very hot +1 to +4 C anomalies, almost the entire sea ice edge region in the Arctic with +1 to +4 C readings including a hot spot near the Nares Strait showing extraordinary +3 to +4 C departures, and two large areas of the Equatorial Pacific — one west of New Guinea and the Solomon Islands and the other off the West Coast of South America — showing +1 to +3.5 C departures.
Significant cooler than normal areas are confined to the Northwest Pacific and a stretch of the Gulf of Mexico off Texas. Another cool zone off of Greenland is likely the result of regional surface water cooling due to ongoing and increasing glacial melt, north wind bursts pushing sea ice out of Baffin Bay, and an expanding zone of fresh surface waters flowing from West Greenland into the North Atlantic.
Overall, the global ocean surface is very, very hot, likely near or above all-time record high temperature departures.
El Nino Continues to Tighten Grip on Pacific
Trends toward El Nino continued in the Pacific with the current strong, high-temperature Kelvin Wave persisting through its upwelling phase. By May 18, +3 C or higher temperatures had reached the surface off Western South America with +4, +5 and +6 C readings only about 25-60 meters below. Upwelling from 140 East Longitude to 130 West Longitude and down-welling off the coast of South America also continued to flatten the 20 C isotherm, providing a west-to-east pathway for warm water propagation.
Kelvin Wave May 18
(May 18 Kelvin Wave Monitoring by NOAA’s Climate Prediction Center.)
Over the past week, Nino zones showed either maintained temperatures, very slight cooling, or surface temperature increases. The Nino 4 zone in the Central Pacific remained at +0.8 C even as the key Nino 3.4 zone in the East-Central Pacific showed slight cooling to +0.4 C. Nino 3 in the Eastern Pacific continued to warm, hitting a +0.6 C positive anomaly. Meanwhile, readings directly off the coast of South America rose to a rather high value of +1.3 C.
Trade winds remained weak or ran west-to-east along the equator. Though no strong counter-trade west winds were visible over the past seven days, numerous areas of weak west winds emerged. Overall, the trades in this large zone were confused and erratic, harried by the development of low pressure system after low pressure system along the equator.
These conditions show an ongoing trend toward an ever-more-likely El Nino by Summer-to-Fall of this year. Sea surface and near surface heat content at high to very high levels during the ‘cool’ upwelling phase of the current Kelvin Wave hint at a Pacific Ocean prepping for a strong El Nino event should favorable weather conditions continue. Extraordinary global sea surface temperature departures in the draw up to this potentially severe event show how sensitive the global system is to any El Nino type warming or movement toward a change in Pacific Ocean temperature states.
In short, global temperatures appear to be on a hair trigger to rise.

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