It’s Official NWS says “El Nino coming”

Last fall we had a huge fall of acorns. Now (end of summer another, light so far,  fall of acorns that started about 4 weeks ago (middle of summer). I called Max to gloat that this confirmed my theory about a coming El Nino event this winter. Now NWS has jumped on my bandwagon (non peer reviewed) that Quercus agrifolia predicts future weather events more than a year in the future.

here is an abstract of a paper by Steinberg, Peter D. 2002

He thinks that from the studies he’s seen that there is probably no direct correlation between future (or even past) rainfall and acorn production. I believe that if it was correlated to future El Nino or future drought there might be a connection.  And a convenient predictor 18+ months in advance of El Nino events. At least that’s what I’ve observed here over the last 3 El ninos in Topanga.

Also in a paper by W. Koenig et al;  the researchers were unable to reach a conclusion on a definitive correlation between rainfall and acorn production in subsequent years.

Of course acorn production is a more complicated mechanism than prior years precipitation and depends also on more than just future rainfall projections. It also depends on trailing indicators like insect predation, and possibly subtle temperature and humidity variations during spring pollination. Of course those variations could also be predictors of future high rainfall seasons.

Acorn crops usually fall in November, this year 2009 we are having a large fall now, Aug Sept.

Q. agrifolia crop Sept 09
Q. agrifolia crop Sept 09

But I haven’t seen at least posted on the web a link between acorn production and future El Nino events up to 18 months away.

Need to find acorn crop production chart.

I say mild El Nino 09-10

In some places the oak seedlings are so thick that it looks like six inch high ground cover. The quercus agrifolia last winter dropped a pretty big crop of acorns. Not as many as they dropped in winter 03-04 that preceded the 04-05 El Nino but still quite a lot.

oak seedlings spring-summer 09
oak seedlings spring-summer 09

Since I believe the Quercus agrifolia anticipate the climate and don’t just react to it, the indication of them setting out seedlings in advance of the El Nino shows that they (know?) anticipate a large rain event is coming. They drop a lot of acorns in a relatively dry year to get seedlings established. Over the summer those seedlings will be thinned out and by the time the rains come in the late fall those that survive will be positioned to take advantage of an abundant rain season.

Of course the oaks exist on a different time scale than humans. To them season to season is like another day to us. The last time the El Nino came it seemed like they looked out and (“said”)  “it looks like it’s going to rain tomorrow, we better get these plants started.” And they shook off a bunch of acorns to get the process going. It just so happens that that was in the winter that preceeded the El Nino.  These oaks don’t so much react as adapt to and anticipate  coming weather events. That’s why the statistics of acorn production  may look  like they don’t have any relationship to climate events. Thats because if we would look for the oaks to be a trailing indicator the statistics wouldn’t make sense.