From the “bigger computers and newer models don’t necessarily produce better predictions” department and the INSTITUTE OF ATMOSPHERIC PHYSICS, CHINESE ACADEMY OF SCIENCES comes this curious observation.
Why has ENSO been more difficult to predict since 2000?
El Nino-Southern Oscillation (ENSO), which is one of the most striking interannual variability in the tropical Pacific, has been extensively studied for several decades. Understanding the changes in its characteristics is still an important issue for worldwide environmental and socioeconomic interests. Clear decadal variations exist in the ENSO’s predictability, with the most recent decade having the lowest ENSO predictability in the past six decades.
“The forecasting reliability during the period 2002-2011 was relatively lower than that in the 1980s and 1990s.” Observed Dr. Fei Zheng from Institute of Atmospheric Physics after he and his team examined the ENSO prediction skills of 20 state-of-the art models. They explored the possible reasons of modulating the decadal variations in ENSO’s predictability, and recommended the Bjerknes Feedback (BF) intensity, which dominates the development of ENSO, to determine ENSO predictability.
They found that decadal variations in BF intensity are largely a result of the sensitivity of the zonal winds to the zonal sea level pressure (SLP) gradient in the equatorial Pacific. Furthermore, the results show that during low-ENSO predictability decades, zonal wind anomalies over the equatorial Pacific are more linked to SLP variations in the off-equatorial Pacific, which can then transfer this information into surface temperature and precipitation fields through the BF, suggesting a weakening in the ocean-atmosphere coupling in the tropical Pacific.
For future research and forecasting practice, Zheng suggested, “More attention should be paid to off-equatorial processes in the prediction of ENSO during the low-ENSO predictability period.”
Their findings were recently published in Geophysical Research Letters.
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The paper: http://dx.doi.org/10.1002/2016GL071636
Dr. George Philander, the father or at least uncle of ENSO, told me over a decade ago that his research, published in one of his books, indicated that in an increasingly CO2 warmed world El Nino would dominate over La Nina, I believe in a positive feedback mechanism.
Is the fact of the Earth is rotating taken into consideration?
Isn’t the ultimate driver of all this climate silliness the Sun? Hence the name “Solar System” ? Just asking, I’m new here.
Phone may be powered by a battery but that does not explain all the things a phone does, Kivy. Of course a flat battery is one thing to consider if the phone behaves unusually, but not the only thing. Is that what you were asking? I think we all ask that at first.
But without the sun there would be no batteries or humans or earth or solar system.
It’s about fricken time someone published this. That it took this long to look back to see if the models were any good seems to me to be evidence they were not altogether enthralled with performance and only published when they observed a “badder” string of predictions. Talk about making lemonade out of lemons!
Notice that their ability to reliably forecast El Nino started in the 1970s with the advent of the renewed natural warming trend. To my mind that shows that part of any warming trend will include a dominant positive/El Nino pattern in the ENSO regions.
Their failure to reliably forecast conditions after the mid 2000s coincides with the switch back to a cool trend. The ENSO regions should favor negative/La Nina conditions until around the mid 2030s, imo.