Water temperatures in the equatorial Pacific Ocean rose drastically last week, prompting expectations of an upward warming trend that would confirm the development of El Nino.
Sea surface temperature (STT) anomalies in the Nino 3.4 region (see image below) showed the highest value of the year at +0.9ºC on June 20, according to data from NOAA seen by Undercurrent News.
This is important to define the event as El Nino since scientists classify the intensity of the weather phenomenon based on STT anomalies exceeding a pre-selected threshold in a certain region of the equatorial Pacific.
Warm water incursion east to west |
Thus, NOAA defines El Nino as five consecutive overlapping 3-month periods at or above the +0.5°C anomaly in the Niño 3.4 region.
The growth of temperature anomalies from +0.4°C in mid-April to +0.9°C now has encouraged projections of an upward warming trend confirming the development of El Nino.
'This is a big jump in temperature, from now on waters will hardly be cooled, the event is irreversible,' oceanic scientist Luis Icochea told Undercurrent.
Icochea, who in April said that abnormally high temperatures were reminiscent of 1997-98 – when took place one of the strongest El Nino’s ever – is confident El Nino will develop this year.
Note the cooler water to the east in normal years |
'Everything suggests El Nino will be very strong, without ruling out the possibility of an extraordinary event,' Icochea said.
Abnormalities of sea surface temperature in Peru have been noticed already in May, as anchovy has moved to the south, near the shore, where industrial fleet is not allowed to operate.
In the north-center area — with a first anchovy season’s TAC of 2.53 millon metric tons — industrial fleet is seen poor catches so far.
By June 11, industry players said only 36% of the anchovy’s total allowable catch had been caught.
'Fishmeal players in Peru will be the most harmed by El Nino, as anchovy is the resource most affected by the weather event,' Icochea said.
To avoid the increased temperatures, pelagic fish such as anchovy will have to move to cooler, deeper waters where feed is available and there are suitable oceanographic conditions.
On the other hand, the phenomenon could mean higher catches of other species for human consumption such as hake — which is showing already a biomass improvement — tuna, mahi mahi, swordfish or shark, Icochea said.
by Alicia Villegas
Report and images courtesy NOAA and Alicia Villegas
I sailed from Panama to the Galapagos Islands and on to The Marquesas Group in September 1997, the last time the currents were exceptionally warm and as illustrated in the lower chart.
In the upper image white area you can see a black dot. That is the Galapagos Islands which are smack in the centre of the warm waters. The Marquesas Group is 3200 nautical miles to the west but only seven degrees south, so you can see how El Nino affects the sea temperatures more than half way across the Pacific.
We experienced the South East Trades a few points further to the south than normal which gave us quite lumpy cross seas for the 3200 nautical mile passage to the Marquesas. This was offset by the wind being steady and no squalls, so we averaged 7 - 9 knots, reeling off 180 nautical miles per day and making landfall at Taiohae Bay, Nuku Hiva eighteen days out of Puerto Ayora, Galapagos.
The most notable events or lack of was the almost total absence of bird and sea life. Not one whale was spotted, very few dolphins and from memory we caught only three fish ( Tuna or Mahi Mahi ) for our dinner. Under normal conditions one of these species would jump onto our trailing lures most evenings.
This phenomena we put down to the El Nino conditions prevailing that year, the fish perhaps moving off to cooler waters, taking the bird life with them.
Cruisers contemplating this passage in 2014 should make note of the conditions they are likely to encounter enroute. Good luck, fair winds and kindly seas.
You can read much more about the cruising lifestyle on passage in my book 'Sailing Adventures in Paradise' downloadable from my website http://www.sailboat2adventure.com/
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