Why Is The Water So Cold In San Diego

Spring is here...and summer is coming!  That means the water warms up...at least by California standards. Soon, south swells (waves from the south)  pump consistently great waves for beginners along our beaches and it's a prime time for surf lessons in San Diego.

But even in the spring and summer, when air temps are in the low 80's, at just about every lesson we teach we hear the comment, "Whoa-that is some cold water!"  So what's the deal?

Our water temps do warm up to mid 60's and 70's, which, when using one of our top-tier wetsuit rentals, is really pretty comfy.  But it's a far cry from the Atlantic coast which easily reaches the 80's.

The reason is a process called upwelling.  It's a pretty simple idea.  Wind and currents pull the warmer water at the top (warmed by the famous San Diego sunshine of course) away from the beach and that water is replaced by colder water from the bottom of the ocean floor.  And sadly, as soon as that colder water warms up in the sun, it's pulled away again for and colder water replaces it.

The good news?  That colder water is super rich in nutrients picked up from the bottom of the ocean.  That spurs plankton blooms, which attract lots of fish, which is why you'll have a great chance at surfing with dolphins, sea lions, and seals!

Photo Credit: NOAA

 Are you a kid or parent of a kid who digs fun ocean facts like this?  Check out Ocean Adventure Camp where kids learn tons of great marine biology!