Catalina Marine Society Studies Marine Environment

nia and taking up recreational diving as a hobby, Gelpi applied his oceanography experiences from diving to the physics of remote sensing using very sophisticated machinery.

By: KATHERINE M. CLEMENTS

CATALINA ISLAND — Seventy-one percent of the Earth’s surface is water-covered, and the oceans hold about 96.5 of all Earth’s water, making the marine environment a very significant focus for humans.

The Catalina Marine Society (CMS) is a non-profit membership corporation founded in 2009 in Los Angeles by scientist Craig Gelpi with a mission to marshal volunteer resources to study the marine environment of Catalina Island and the Southern California Bight. The Southern California Bight is a 692-kilometer-long stretch of curved coastline that runs along the west coast of the United States and Mexico, from Point Conception in California to Punta Colonet in Baja California, plus the area of the Pacific Ocean defined by that curve.

Since its beginning, the Catalina Marine Society has benefited the island in more ways than one. Projects and work give boaters and divers an excuse to go to the island and engage in assignments supporting local businesses, such as kayak rentals, dive stores, and restaurants. The island’s reputation spreads globally when the results of their work are published in international journals, and the findings showcase how unique Catalina is and how its location in the center of the Southern California Bight contributes to that uniqueness.

Gelpi has a B.S. in physics and math from Tulane University and a Ph.D. in physics (space physics) from the University of Houston. After moving to Califor-

“Wanting to do useful things with my diving, I sought organizations who were collecting data with divers,” said Gelpi in an email to the Log. “Then I found that the diving was fun, but the organizations had little capability to actually analyze the data they collected. The Catalina Marine Society was founded to provide that little extra structure needed to convert the fun of diving to useful scientific products.”

The Catalina Marine Society has several field programs that crucially depend on volunteers. These programs include the David Tsao Continental Thermograph Array, where volunteers deploy temperature recorders on the seabed off both the mainland and Catalina.

Currently, the Catalina Dynamic Ocean Chemistry program (sea-doc) needs divers and boaters to deploy underwater computers that measure ocean chemical parameters at their Dirk Burcham Scientific Mooring in Two Harbors and the Jim Updike Seabed Station. In addition to the projects, actions are needed to sustain such an organization, such as maintaining and expanding the website, organizing fundraisers and social events, helping with grant proposals, and recruiting students and professionals to analyze collected data. The Society has no paid staff, and everything is accomplished through volunteerism.

The CMS has achieved accomplishments, and one with the most significant impact is its analysis of how seasonal temperature changes with depth. From data gathered by temperature recorders deployed and retrieved around the island by hundreds of dives by the Catalina Island Conservancy, the CMS was able to figure out the rate of nutrient flows from the seabed to surface waters, where all plants from giant kelp and phytoplankton use the nutrients to grow and sustain the food web.

According to Gelpi, this nutrient flow process differs at Catalina from that found at the Northern Channel Is- lands and the Northern and Central California Coasts due to Catalina’s unique location within the Southern California Bight. Surprisingly, the research found the numerical values for this flow are the same as required for mixing the very deep, cold water at the bottom of the ocean to the surface, a vital component of climate mechanisms. The oceanography community has expended much effort to measure this, for example, by dispersing chemicals in the water and observing how fast they mix in the water column, being performed economically using temperature measurements.

The Catalina Marine Society has several projects, including:

- The David Tsao Continental Thermograph Array

- The Monterey Bay Thermograph Array

- The Catalina Dynamic Ocean Chemistry program, including the Jim Updike Seabed Station, which was deployed in May this year.

“We also have the Remotely Determined Ocean Conditions (RDOC) program.,” said Gelpi. “Last year, we executed a large RDOC experiment within the Avalon Dive Park, where divers deployed instruments at the bottom that measured the height of waves while a camera above the Casino recorded imagery of the ocean surface above the sensors. The objective is to figure out wave heights and wave directions using camera imagery. The work is ongoing and very promising. If successful, we hope eventually to monitor ocean conditions with cameras at beaches known to be hazardous, such as Monastery Beach near Pacific Grove up north, and give [a] warning when waves are particularly dangerous.”

For more information about the Catalina Marine Society or for those interested in volunteering, please visit https:// www.catalinamarinesociety.org/.