Stubborn ENSO (from 1.28.13)

Global climate conditions continue to behave as previously discussed, with the tropical Pacific very reluctant to move into an El Nino state, and instead having a current pre-disposition towards favoring La Nina’s.   The primary driving force for this, and I say primary for as with climate no single force alone can be adequately used as a predictor, is the negative state of the Pacific Ocean, called the PDO (Pacific Decadal Oscillation).  A positive PDO has warmer waters in the equatorial Pacific and colder waters in the North Pacific, while a negative PDO has cooler waters in the equatorial Pacific and warmer waters in the North Pacific.  From the above description, intuitively it makes sense that El Nino’s have an “easier” time of it in positive PDO (warmer pool of water near the equator) and that La Nina’s have an “easier” time of it during negative PDO (cooler pool near the equator).   Many climate models in early to mid-2012 were predicting an El Nino to occur by year’s end, and indeed the tropical Pacific warmed, but never had enough to do much more than that, and in fact we are now on the threshold of another La Nina, as the tropical Pacific has cooled yet again, though currently stalled at the moment.  A further bit of La Nina strengthening is expected again as we head into boreal spring, and that is not necessarily good for mid-latitude row crops.  Thus, we are faced with the possibility of additional supply problems in 2013.

 

This is not to say that El Nino’s cannot occur in negative PDO, the historical record shows that they most certainly can.  However, it takes a more complete synchronization of the multiple forcing factors in this type of climate regime to initiate one.  At times in the 1950’s and 60’s, (last period of prolonged negative PDO), the tropical Pacific went 5-7 years without an El Nino.  The state of climate forecasting is not advanced enough to make this bold a statement, but it has been a number of years already.   Once again, several climate models are forecasting an El Nino by the end of 2013.   Will this be the time the models get it right?  In any event, that is a good 9-12 months off, and for the balance of the already in progress Southern Hemisphere growing seasons and the upcoming Northern one, the background climate signal for 2013 will be mostly similar to that of the last few years.  As major droughts have struck globally in each of those years, we must remain on alert that such a possibility exists.   As of this writing, after a very wet start to the growing season in the southern part of South America, dryness has set in from mid-December onwards, and  the prospect for soaking rains in tenuous at best through mid-February if not the whole month.  As “unusual” as this seems to repeatedly have major crop issues, as this was not the case during the positive PDO “global warming” period of the last 30 years….let me repeat this for emphasis…the period from the mid-1980’s until several years ago was notable for its ABSENCE of devastating crop failure with very few major mid-latitude droughts nor Asian monsoon failures…..the current pattern resembles more the period around the 1950’s and 1930’s….which were quite notable, as history attests.  As persons with vested interests in agriculture, we do not have the luxury of worrying about 50-100 years in the future when pressing problems face us in the present.  As relates to climate prediction, a twist on an old phrase…”those who choose to ignore the past, will miss the future”.

 

Flat Earth Risk Management

1.28.13

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