We have safely and successfully returned to land after the end of our 2019 CCE-LTER Process Cruise! On Friday, we sailed back past Point Loma into San Diego Harbor and offloaded our month’s worth of scientific gear and samples. Only time and sample analysis will tell us what we found, but we know we conducted plenty of science! Over the course of 32 days, we did 93 CTD casts (ran out of time for the final 7), 26 MOCNESS tows, 3 SeaSoar deployments, and innumerable Bongo tows and trace metal CTD casts – not to mention Zippy’s solo excursion!
The numbers only capture half the story, though. Going to sea with 57 people on a 280-foot ship inspires you to get to know those around you, and our party bonded across scientific and geographic lines. We look forward to future collaborations around the world! We’ll miss the daily sightings of whales and dolphins, though.
You know you’re off Central California in the summer when you wake up to the ship’s fog horn going off! Overnight, we sailed into thick fog off Monterey, and this morning we could barely see 20 feet away. Amazingly, as we sailed toward land, the fog lifted and we were greeted with stunning views of the mountainous Big Sur coastline gleaming in the morning sun. We even saw a pod of whales feeding several hundred feet off the ship’s bow.
Yesterday we ended our 72-hour SeaSoar transect and recovered the SeaSoar. This morning, we launched the Moving Vessel Profiler (MVP) for another all-day transect. Similar to the SeaSoar, the MVP gets towed behind the ship and completes diving profiles up and down of the upper 200 meters of the ocean. The MVP can go closer to shore, which is advantageous because we want to sample the waters right off the coast – sometimes with the bottom only 50 m deep! We are surveying this area off Big Sur in preparation for two sampling transects tonight and tomorrow night. Transects are where the ship sails in a straight line bisecting an oceanographic feature – in this case, various arms of the upwelled filament that we are tracking – and the science team conducts a series of CTD casts and zooplankton tows (to be explained more in-depth later).
We will be transiting in and out of the fog this afternoon
as we zig zag inshore and offshore on our MVP transect. We are hoping for clear
skies tonight as we start our first transect! In the words of Neil Young, “It’s
better to burn out than to fade away”.
We have officially begun our cruise’s scientific measurements! Tuesday evening, we deployed the SeaSoar, a small yellow airplane-shaped vehicle about the size of a bicycle. We will tow the SeaSoar behind the ship for three days as we sail in a radiator grid pattern (long lines from south to north and back south) off Monterey, California. The SeaSoar descends from the surface down to 300 meters and then back up, changing the pitch of its wings to control its direction. It will repeat this yo-yo pattern continuously the whole time it is deployed. SeaSoar measures water temperature, salinity, oxygen, fluorescence (an indicator of how much chlorophyll is produced by phytoplankton), and several other biogeochemical variables. We combine the SeaSoar dives into cross-sectional profiles to give us an image of what the subsurface waters off central California look like.
We do this profiling transect at the beginning of our cruise to identify and determine the water ‘feature’ that we will sample throughout the month. Our goal is to find a newly-upwelled water filament (think a triangular-shaped parcel of water, with the wide base along the coast and the tip pointing offshore) and to follow that filament as it moves progressively offshore. We have identified a potential filament off Monterey using satellite measurements of sea surface temperature and water currents, so we are cruising through the area with the SeaSoar to get additional information about the subsurface structure of the feature. We hope that this emerging filament continues to grow and move offshore, so that we have time to sample various areas of it!
We have been graced by lots of animal sightings while we do the SeaSoar survey. As we were preparing to deploy the SeaSoar on Tuesday evening, a mola mola floated by at the surface! Molas are oval-shaped bony fish with very flat bodies. They often float on their sides at the surface of the ocean, resembling large pancakes. Sharks and killer whales have been known to sample them (or perhaps use them as frisbees), but overall they are rather unpalatable. We have also seen albatrosses and other seabirds. Wednesday afternoon the sky cleared for a beautiful sunset with pods of dolphins and whales cruising alongside the ship!
We are officially underway on our 2019 CCE-LTER Process Cruise! We left San Diego Harbor yesterday afternoon under sunny skies and smooth sailing conditions, and we are now heading north toward Monterey, California. We won’t see Point Loma again until September!
The goal of our monthlong cruise is to track water filaments that are upwelled in near-coastal waters off central California and flow out to the open ocean several hundred miles offshore. We are measuring various aspects of the biological production associated with filaments: viruses and bacteria, phytoplankton and zooplankton, along with the nutrients that fuel their growth. Our cruise the latest installment in the California Current Ecosystem Long-Term Ecological Research (CCE-LTER) Program, which was started in 2004. The program consists of a core body of scientists from Scripps Institution of Oceanography and collaborators from numerous other institutions, as well as visiting scientists and volunteers from around the world. Our current cruise includes participants from as far away as Canada, France, Luxembourg, and Ghana! Yesterday evening, we stopped 20 miles offshore to test our scientific sampling equipment. Some of our graduate students and volunteers are out on their first sea trip ever, so they got a glimpse of the deployments we will be doing during the cruise. Stay tuned for future features on our various types of sampling equipment and the scientists who use them.
We are sailing on the Research Vessel (R/V) Atlantis, which is operated by Woods Hole Oceanographic Institution (WHOI) out of Massachusetts. Scripps and WHOI are both members of the University-National Oceanographic Laboratory System (UNOLS), under which ships are built for certain institutions but are shared with other institutions based on where in the ocean the ship is and where a given cruise is going. The Atlantis has a unique claim to fame: it is the mother ship of Alvin, a submersible vehicle that can carry scientists to the seafloor to explore deep-sea communities. The Atlantis and Alvin have been sampling hydrothermal vents in the Pacific Ocean for the past year, so the ship was in the right spot for our cruise. We don’t have plans for Alvin dives on our cruise, but you never know what could come up at sea!