Shows that, at least in a computer model, the ENSO (El Nino Southern Oscillation) can occur all on it’s own as a natural process.
Nice to have that “confirmed” by a model. (Guess it is kind of hard to run an experiment in the real world…)
In a series of Atmospheric model simulations coupled to a simple slab ocean model it is illustrated that El Niño type of SST variability can exist in the absence of any ocean dynamics. Atmospheric feedbacks in cloud cover and changes in the wind field can produce positive and delayed negative feedbacks, that together with the heat capacity of the upper ocean can produce a damped interannual oscillation in the equatorial Pacific, that is comparable in strength and has characteristics to the observed phenomenon. The evolution of the SST pattern is similar to the SST-‐mode of El Niño, but is entirely controlled by atmospheric feedbacks. The results challenge and extend our current understanding of the feedback mechanisms of El Niño in climate models and may also highlight possible atmospheric mechanisms that could partly control some observed ENSO events.
Well, glad all the science was settled about Global Warming before this came out…
Hate to think we’d been running back and forth between a warming 1930’s to a cooling 1960 and back to a warming 1990’s all as a natural 60 year cycle with no need at all for CO2 in the process…
(For the inevitable slow to think it through critics: Yes, the PDO is not the ENSO. But if ENSO is a natural emergent behaviour then the long term impacts of a similar process can manifest as a similar though longer term shift, the PDO.)