BY ANNELIESE MOLL
For the UAS Whalesong
At some point over the last few months you have most likely heard the name “El Niño” while you were listening to the radio or watching the weather portion of the news. You might have gathered that it has to do with increased amounts of rain or storm frequencies, but there is a bit more to it than just that.
El Niño and La Niña are two very different pieces of a weather patterns that have huge impacts on weather around the world. According to the National Oceanic and Atmospheric Administration, they are a phases of the El Niño-Southern Oscillation cycle, a term that scientists have applied to describe the fluctuations in temperature within the ocean and atmosphere in the east-central Equatorial Pacific. These periods are determined by unusually warm sea surface temperatures (El Niño) or by unusually cold sea surface temperatures (La Niña). Either phase can last anywhere from nine to twelve months and are reported to average every four to seven years (McPhaden 1993).
El Niño begins with warm water from the western Pacific moving east toward the coast of South America every year. Usually, it does not make it and just ends up pooling around Indonesia, but during El Niño this warm water makes it to the shore of the northwest coast of South America. To be officially declared an El Niño, sea surface temperatures around the Equator need to be at least 1.5 degrees C above standard temperatures for three months.
Currently, we are experiencing weather patterns consistent with El Niño. Early in September, NOAA released an El Niño advisory, and as a part of that report included that there is a high probability of this El Niño becoming the “strongest on record” and continuing into the spring of next year.
The results from El Niño can be more storms of greater magnitudes, heavy rain, or snowfall. Some have questioned if El Niño may provide some relief for California’s drought, but NOAA researchers do not believe that this El Niño will be strong enough to greatly impact the multiple years of drought California has seen.
While is El Niño may not be enough to help California, there have been some particularly interesting for many Alaskan fishermen and scientists over the course of this last summer. One such event was the discovery of sunfish within the Gulf.
These are huge tropical fish that are commonly described as “swimming heads” because of their strange shape. On average, these fish can reach adult lengths of six feet (1.8 m) horizontally and around seven feet (2.1 m) from the top of the dorsal fin to top of the anal fin. They hold the title of the heaviest boney fish, with weights able top 4,000 lbs. Currently, there is no data on the growth rates of wild sunfish. We do know that their diet consists of foods such as: jelly fish (gelatinous zooplankton), algae, crustaceans, molluscs, and various species of fish (Pope 2010).
These normally more tropical fish were found just outside of the entrance of Prince William Sound. Stranger still, researchers conducting a salmon trawl survey caught two others earlier in the summer (Miller 2015). Other strange species that have been caught over the summer include market squid, several species of tuna, as well as a thresher shark. For some of those organisms, this may not be their first appearance within Alaskan waters, but most were noted as being the most northern appearance ever recorded. If Alaskan waters continue to be warm and different species begin moving up, it could result in dramatic shifts within ecosystems.
McPhaden, M.J., 1993: TOGA-TAO and the 1991-93 El Niño-Southern Oscillation Event. Oceanography, 6, 36-44.
Miller, M. (2015, September 15). Warm-water fish increasingly spotted in Alaska waters. Retrieved October 5, 2015.
Pope, E. C., Hays, G. C., Thys, T. M., Doyle, T. K., Sims, D. W., Queiroz, N., … &
Houghton, J. D. (2010). The biology and ecology of the ocean sunfish Mola mola: a review of current knowledge and future research perspectives. Reviews in Fish Biology and Fisheries, 20(4), 471-487.