The Summer Of Our Discontent

By Dr Rob Brander on December 15, 2010 in Other

I hate to put a dampener on things, but this summer ain’t looking so hot – rain, wind, cold water, mediocre surf and bluebottles are all more than likely. I’m hoping I’m wrong, but we are experiencing what is called a La Nina climate phase. Most of us have probably heard of the terms ‘El Nino’ or ‘La Nina’, and may even have had to translate these in a pub trivia competition, but what do they have to do with the beach?

The El Nino/La Nina Southern Oscillation (ENSO) is a large-scale climate phenomenon that fluctuates over three to seven year periods. It’s related to warming and cooling phases of the surface water temperature of the Pacific Ocean between Australia and South America, caused by atmospheric pressure imbalances on each side of the Ocean due to variations in Walker Circulation and Kelvin Cycles*, but I digress. All you need to know is that La Nina is the cold phase, which leads to crap weather for us including lots of rain and an increase in persistent winds from the east and northeast. This is where it gets interesting for us beach addicts because persistent northeasterly winds equal cold water!

If you dig out the May 2010 edition of The Beast from that basket of old mags next to the loo, you will find my article describing how strong northeast winds lasting for a few days or more push nice warm surface water towards the coast, but physical phenomena known as the Coriolis Force (due to the earth spinning) and Ekman Transport (a type of ocean current circulation named after a European bloke) cause this warm water to be deflected offshore. To replace it, cold water rises from the depths in a process known as ‘upwelling’. Remember early December? The wind was howling from the northeast and the water was freezing.

Now aside from cold water temperatures, these winds also tend to bring in lots of bluebottles, which may look like cute pieces of blue bubblegum but have very long tentacles beneath them armed stinging cells that pack a wallop of pain. Bluebottles generally like warm water so they tend to hang out offshore in the East Australian Current. However, those pesky northeasters that last for days tend to blow the ‘blueys’ straight toward us. Remember, if you see them washed up on the beach, they’re probably in the water as well.

To make matters even worse, during a La Nina the surf conditions are usually a whole lot of mush due to all the wind.

Thankfully the news isn’t all bad though. Sometimes there’s nothing better on a rainy day during the holidays than to curl up with a good book, like Dr Rip’s Essential Beach Book, for example, which allows you to immerse yourself vicariously in the joy of beaches without even going outside!

Dr Rip is giving his FREE ‘Science of the Surf’ talks throughout January around the Eastern Suburbs. Check out www.scienceofthesurf.com for more info.

*This is quite possibly my most hardcore scientific statement to date. My book is not nearly as complex as this and has lots of nice pictures.