A few weeks ago, a student-led research cruise onboard Scripps Institution of Oceanography’s R/V Robert Gordon Sproul was visible from Birch Aquarium. Naturally, guests, staff, and volunteers were all curious about the big blue ship zig zagging off of La Jolla Shores. It turns out, these students were conducting exciting research in the waters over La Jolla Underwater Canyon. Check out the above photo gallery from the ship!
Madeleine Harmann, a Scripps Oceanography student onboard, let us know what the science team onboard the Sproul was up to:
Over the last week, our team has been studying mixing patterns and internal waves in the La Jolla Canyon. Internal waves are waves that occur in the interior of the ocean where there are layers of water with increasing density——on the surface there is warm, fresh water from the sun and the rain and beneath that there is cold, salty water that was formed at the poles. Just like surface waves, internal waves can be generated very far away and travel across entire ocean basins until they reach the coast. And, just like surface wave, they can roll up and break when they do! This breaking creates lots of turbulence and mixing, and that mixing moves things like heat, oxygen, nutrients, carbon dioxide, and even plankton to different depths in the ocean where marine life can utilize them. The movement of heat also influences the way that the ocean interacts with the climate to produce weather patterns and buffer the increasing heat in our atmosphere.
Submarine canyons like the La Jolla Canyon are prime locations for the breaking of internal waves because they are so steep and complex. From our heavy towed instrument, SWIMS (shown in attached pictures), we can see that mixing in real time on the screens in our computer lab. We are working around the clock to chase that turbulence and figure out where it occurs, how strong it is, and how it moves nutrients up into the water column. If you’ve ever been snorkeling or kayaking over the the La Jolla Cove, you can see that there is an abundance of marine life—and that’s because the La Jolla Canyon funnels nutrients into it and allows for lots of plankton and plant life to thrive!
A fun fact about the La Jolla Canyon — in the 1950’s Jaques Cousteau took his flying saucer down into the Scripps canyon (which is the narrow branch of the canyon that ends at Black’s Beach) and saw that it had walls so steep that they were inverted at places. In the 1970’s, Doug Inman and his colleagues put moorings in the canyon that were destroyed by strong currents within a week! It’s a hairy pace, and no one has been back to study its currents since then… until now! When the R/V Robert Gordon Sproul is closest to shore, we are very carefully surveying the canyon with our instrument — and hoping we don’t hit any overhanging ledges!
Thanks to Maddie and the rest of the team for the inside scoop! It’s always exciting when guests can see Scripps Institution of Oceanography science happening in real time. Always keep an eye on the horizon for ships in the Scripps Oceanography Fleet, and don’t miss the excitement surrounding America’s newest research vessel, R/V Sally Ride!