Ocean Science 101: El Nino Update

NOAA’s Climate Prediction Center (CPC) has just issued the latest update on the El Nino conditions…and the current data is showing that the El Nino is strengthening.

When I did my last El Nino update in september, which you can find here…

http://socalforecast.blogspot.com/2009/09/ocean-science-101-effects-of-el-nino-on.html

…the average increase is SST (Sea Surface Temps) was about 0.9 to 1.1 degree Celsius above the seasonal “base” temperature.

Over the last month there has been a pretty sharp jump in SST’s in the areas normally associated with El Nino conditions, particularly the Eastern Equatorial Pacific. The new El Nino strength is showing above average temps around 1.5 to 1.75 degrees Celsius which puts us squarely into the “moderate” range…but edging up into the “strong” category.

Check it out.



And this chart shows the breakdown by subregion…El Nino Zones 3.4 and 4 are both areas that have a direct effect on the West Coast.



Zone 4 is located along the equator over by Hawaii…this areas is pretty important from a “winter storm” standpoint since this is where a lot of the tropical/extra-tropical moisture is fed into the colder high-latitude systems. As this region warms it means that we have a better chance of larger/more-intense storms forming closer and in better position to send swell to Southern California.

Zone 3.4 is the Eastern Pacific Tropical region…where we see most of the tropical storms, that can send Socal S-SE swell, spin up. This isn’t as crucial an area for our winter surf, but it does help to support the increase temps in Zone 4 and add moisture to that sub-tropical jet-stream that sometimes forms during the winter, increasing our local rain (and snow).

Lastly here is a chart that shows how El Nino is affecting water temps at deeper depths.



It shows that El Nino isn’t a shallow phenomenon that could break down quickly, but instead is a well-entrenched shift in both oceanic and atmospheric conditions that will continue to affect us for the next several months.

Current long-term El Nino outlooks are calling for this episode to hold or possibly strengthen through January 2010 and then start a slow cooling trend as we move through the middle to second half of the year.

What this means surfwise?

Like I said in the last update…having El Nino conditions does not guarantee that we will have good winter surf, but it definitely increases the odds. Now that the Nino is strengthening in the areas that directly affect our storm production and positioning, it looks like the odds of getting decen waves are going to get even better. I know one thing for sure…we have already had more waves this winter than we did all of last season, which equals a win in my book.