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Wednesday, May 13, 2015

Super El Nino Likely as Huge Warm Water Wave Hits West Coast, Extreme Marine Die Off Developing

by Climate Change SOS, Daily Kos, April 30, 2015
Three tropical cyclones churned the waters around Australia on March 11, 2015, including Pam, which reached category 5 and devastated the south Pacific islands of Vanuatu.
attribution: NASA MODIS
Three tropical cyclones churned the waters around Australia on March 11, 2015, including Pam, which reached category 5 and devastated the south Pacific islands of Vanuatu.
In early March, the strongest wave of tropical convection ever measured (known as the Madden Julian Oscillation) by modern meteorology moved into the western Pacific from Indonesian waters bringing an outbreak of 3 tropical cyclones, including deadly category 5 Pam which ravaged the south Pacific islands of Vanuatu. This extreme outburst of tropical storms and organized thunderstorms pulled strong westerly winds across the equator, unleashing a huge surge of warm water below the ocean surface. Normally, trade winds blow warm water across the Pacific from the Americas to Australia and Indonesia, pushing up sea level in the west Pacific. When the trade winds suddenly reversed to strong westerlies, it was as if a dam burst, but on the scale of the earth's largest ocean, the Pacific. The front edge of that massive equatorial wave, called a Kelvin wave, is now coming ashore on the Americas.
A huge surge of warm water from an enormous deep equatorial wave called a Kelvin wave is now hitting the west coast of the Americas. A wave of similar size struck last year bring a massive marine die off to the west coast, but this year's marine die offs will likely be worse because climate models are predicting it will trigger a super El Nino.
Detailed research in California has found that nutrient upwelling was at a minimum in the El Nino year of 1992 and the super El Nino year of 1998. A huge surge of warm water from an enormous deep equatorial wave called a Kelvin wave is now hitting the west coast of the Americas. A wave of similar size struck last year brought a massive marine die off to the west coast, but this year's die offs will likely be global because climate models are predicting a super El Nino. Credit NOAA.
Last year the largest Kelvin wave ever seen in the Pacific ocean developed in February. After it came ashore and the surge of warm water moved up the Pacific coast, the upwelling of nutrient rich cold water dramatically slowed, and marine life began starving up and down the coast of north America. As the warm water moved north from the equator it merged with an enormous mass of warm stagnant water dubbed "the blob" which had built up in the central north Pacific ocean under the mound of high barometric pressure known as the Pacific high. Because the Pacific high had expanded north of its normal position, possibly because of climate change, warm, stagnant low nutrient water covered a large percentage of the surface of the north Pacific ocean. That stagnant water came ashore on the coast of the Pacific northwest and Alaska as the surge of warm water from the Kelvin wave moved up the California coast. The warm stagnant water lacked nutrients to support the growth of krill and copepods which are at the bottom of the food chain. Species that fed on krill and copepods had little to eat. Juvenile birds were the first to be affected by the lack of food. The west coast marine die off is already a crisis but it's likely to get much worse this summer and fall as  the surge of warm water moves up the coast from the huge Kelvin wave now coming ashore.

"The Pacific Coast saw record numbers of dead Cassin’s Auklets this winter. " Audubon.
10,000 baby sea lions dead on one California island — Experts: “It’s getting crazy… This is a crisis… Never seen anything like it… Very difficult to see so much death” — TV: “Numbers skyrocketing at alarming rates”
An unprecedented number of auklets, a tiny sea bird that dives for plankton, were found dead in Fall 2014, apparently of starvation, along the west coast from California to Canada. Nutrient poor warm waters are the probable cause of the lack of food.
Last year, beginning about Halloween, thousands of juvenile auklets started washing ashore dead from California's Farallon Islands to Haida Gwaii (also known as the Queen Charlotte Islands) off central British Columbia. Since then the deaths haven't stopped. Researchers are wondering if the die-off might spread to other birds or even fish.
"This is just massive, massive, unprecedented," said Julia Parrish, a University of Washington seabird ecologist who oversees the Coastal Observation and Seabird Survey Team (COASST), a program that has tracked West Coast seabird deaths for almost 20 years. "We may be talking about 50,000 to 100,000 deaths. So far."
The warming that last year's huge Kelvin wave brought started a global coral bleaching event is likely to get much worse after this year's huge wave of warm water spreads up and down the coasts of north and south America.
“It started in 2014 – we had severe bleaching from July to October in the northern Marianas, bad bleaching in Guam, really severe bleaching in the north western Hawaiian Islands, and the first ever mass bleaching in the main Hawaiian Islands,” said said Mark Eakin, Noaa’s Coral Reef Watch coordinator.
“It then moved south, with severe bleaching in the Marshall Islands and it has moved south into many of the areas in the western south Pacific. Bleaching just now is starting in American Samoa. In Fiji we’re starting to see some, the Solomon Islands have seen some. We’ve already seen a big event."
Bleaching takes place when corals are stressed due to changes in light, nutrients or temperature – though only the latter can cause events of this magnitude. This causes them to release algae, lose their colour and in some cases die off. It is a relatively rare occurrence. Large-scale bleaching was recorded in 1983, followed by the first global scale event in 1998. A second global wave came in 2010.
NOAA's CFSv2 model is forecasting a strong El Nino event will develop this summer and continue through 2015. Warm water along the west coast, combined with weaker than normal winds caused by El Nino will prevent nutrient rich cold water from welling up along the coast. Species that depend on nutrient upwelling will face starvation. Australia's Bureau of Meteorology has an excellent El Nino forecasting model which is also predicting a strong El Nino. Because the jet stream has already gone into an El Nino pattern by moving south over the eastern Pacific ocean and Mexico and further north than normal over the eastern Atlantic ocean, the likelihood of El Nino failing to strengthen is small. Last year's Kelvin wave failed to bring on a strong El Nino because trade winds in the south Pacific didn't weaken but this year they have and waters along the west coast of south America have already warmed. The south Pacific has moved out of the cool mode it was in a year ago.
NOAA forecast of the departure from normal of Pacific ocean sea surface temperatures.
NOAA forecast of the departure from normal of Pacific ocean sea surface temperatures. NOAA's CFSv2 model predicts a strong El Nino with much above normal sea surface temperatures along the west coasts of south and north America up to January, 2016.
The forecast of a strong El Nino brings good news to California. NOAA's CFSv2 model is forecasting above well above normal precipitation for October through December, 2015. Because models are forecasting El Nino conditions to continue through January 2016 there is a good chance that heavy winter rains will break the California drought. The downside will be massive landslides and flooding in areas that have been affected by recent wild fires.

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