Echoes of the Past, Windows to the Future

An upcoming scientific expedition aboard the global-class Scripps research vessel Melville led by students from Scripps Institution of Oceanography at UC San Diego will seek ecological time capsules off the California coast this fall. 

The cruise, called Cal-Echoes, will focus on the Santa Barbara Basin and California’s changing marine and terrestrial ecosystems along the coast.

“The goal of Cal-Echoes is to explore changes in the ocean. We will be investigating what is occurring today while at the same time looking at what happened in the past, in particular since humans first arrived in California 2,000 years ago and also over the warming period following the last glacial period 12,000 years ago,” said Mindi Summers, a Scripps graduate student and chief scientist of Cal-Echoes. “It’s our hope to be able to combine these time frames to better understand California ecosystems today and also make predictions about where they are going in the future.”

Scientists consider the Santa Barbara Basin an ideal location to explore California’s natural history and to seek clues to its future. The basin’s waters are nearly devoid of oxygen and burrowing creatures, allowing the continuous buildup of sediment on the seafloor to preserve fossils from the region’s past, both from the ocean and nearby land. The sediment layers are not unlike tree rings that reveal the year-by-year history of the area.

Researchers and historians have tracked dynamic shifts in California’s land ecosystems, which have seen cold periods that brought forests 3,000 feet lower than today’s levels and warmer stretches that allowed desert scrub to reach the coast.

Cal-Echoes scientists will travel backward in time, across space and habitats, and study organisms ranging from single cells to marine mammals. Researchers aboard the nine-day cruise, which launches Sept. 25, will perform an interdisciplinary analysis of the basin using traditional oceanographic tools such as nets, water sampling devices, and sediment cores.

But they also will employ cutting-edge genomic analyses to investigate ancient genetic materials. The team will seek out fossil DNA found in sediment cores to study ancient organisms that mixed in sediment layers with ash, pollen, fish teeth, and scales to reveal historical snapshots of the marine and terrestrial region.

The historical perspective could also inform fisheries economics. Cal-Echoes researchers will investigate the marine food web from microbes to fish, squid, and seabirds. The researchers will study the diversity of these organisms and historical effects from climate and environmental changes. The new information will be referenced against the historical context provided by the California Cooperative Oceanic Fisheries Investigations (CalCOFI), the unique ocean monitoring program initiated in 1949 off California by Scripps Oceanography, the California Department of Fish and Game, and NOAA’s National Marine Fisheries Service.

“One of the extremely exciting aspects of oceanography is that it’s always a process of discovery. The oceans are a gigantic environment on the planet and yet we know them very poorly, so there’s always the possibility that we will find things which are completely new to science,” said Richard Norris, a Scripps professor of paleobiology. “The core question for Cal-Echoes is: What was California like in the past and where is it likely to go in the future? We’re particularly interested in knowing how California might change as the climate warms up, our population changes, and coastal marine and terrestrial ecosystems change.”

In addition to 14 graduate student researchers, the cruise also will include five middle and high school teachers who will use the expedition for education outreach by bringing Cal-Echoes science and the experience of researching at sea into the classrooms. The teachers will post lesson plans and activities before, during, and after the cruise under National Ocean Science Standards.

The cruise is sponsored by UC Ship Funds, a University of California and Scripps Oceanography program designed to give early-career researchers opportunities to conduct science at sea on a Scripps research vessel.

—Mario C. Aguilera