Did I mention that the ocean doesn’t always behave? We have spent years making measurements in the region around Los Angeles and Orange County along with our colleagues from the sanitation districts, USGS, SAIC, UCSD Scripps, etc. So we think we know the region pretty well. Last spring and this spring we have been flying robotic submarines called gliders (no propeller, see picture below) in the region between Seal Beach and Laguna Beach and offshore about 13 miles.
This vehicle doesn’t move quickly, only about 0.3 meters/second or about 0.6 knots. So if the speed of the ocean currents are very strong the glider can’t make the path that it’s supposed to fly. Up to now, we haven’t had a problem with this. But, ……. last week our glider started heading south toward San Diego at a speed of 1-2 knots, and we could not do anything to make it turn back. It was pointing north and heading south. The currents stayed high for the entire week. We had to chase the glider down to Carlsbad – we think it was hoping to have spring break in Mexico with all the other USC students. We were able to retrieve the glider before she crossed the border into Mexico, and will put it back out when the currents have subsided a bit.