July 25, 2014
Since the Exploratorium opened at its waterfront location more than a year ago, we’ve been engaged in a unique experiment with the National Oceanic and Atmospheric Administration. NOAA’s Pacific Marine Environmental Lab in Seattle lent us a beautiful ocean buoy, outfitted with instruments to measure carbon in the ocean and atmosphere. For the last 15 months, it’s been bobbing in all its white and red glory in the lagoon between Piers 15 and 17, occasionally surrounded by mist from the fog bridge art piece.
Instruments mounted on the buoy have been gathering oceanographic and atmospheric data to help scientists understand how the build-up of carbon dioxide in the atmosphere and ocean affect marine ecosystems. Ours is the only one of NOAA’s CO2 buoys so close to an urban center and a major estuary, both of which add carbon to the bay water. The unusual chemistry of San Francisco bay waters can be a living laboratory for the future, when marine environments become increasingly more acidic (more on that in a later post).
We’ve reached a milestone with the experiment, the first time we’ve pulled the buoy out of the water for maintenance. It’s a complex choreography of forklift, mobile crane and a balky metal watercraft dubbed “the angry bathtub” to lift the one ton buoy from the water onto our outdoor plaza. Over the next week, our marine technician, Chris Raleigh, will be swapping out and calibrating instruments, scaping off marine growth and repainting the faded red striping all in view of the public.
I was excited to get a look at what’s been growing below the buoy’s water line and woke early to get down to the Exploratorium and document this momentous occasion. As expected, the bottom of the buoy was covered in leafy green and lacy red algae, with some mussels,
bryozoans and limpets in between the plants. We even found a few oysters and a small scallop. The shells of the mussels and oysters were very fragile and broke apart in my fingers, quite unlike the thick-shelled tide pool mussels I’m used to handling. I wonder if this could this be from the higher acidity of the water or the fact that these shellfish are protected from wave action.
We even saw growth on the chain floats: solitary stalked tunicates attached along with the slimy colonial tunicates, mussels and osyters. Crawling all around were crabs, segmented worms (which resemble aquatic centipedes), ghost shrimp and some tiny iridescent shrimp of the brightest lime green I’ve ever seen. We took samples and plan to share them with scientists who study invasive and native organisms of the bay.
The buoy will be out of the water for a week, getting its yearly make-over before we lift it back into the bay to start collecting live data once more. In my next post, I’ll discuss what we’ve learned from the carbon and oceanographic data we’ve gathered over the last 15 months.