Earth and Planetary Science
EPS Near-Surface Geochemistry and Geobiology

UC Berkeley undergraduate Ernesto Martinez returns from 3200 km scientific voyage.

Wednesday, August 1, 2012
Ernesto and the water sampling rosette system he used at sea. Berkeley
Canadian Coast Guard Ship John P Tully returned to it\'s Vancouver Island, British Columbia, port after 16 days at sea surveying carbon-dioxide, ocean biology, and related properties in the waters from the coast of North America to a well studied spot in the ocean named Ocean Station PAPA (50N 145W). Aboard the Tully, EPS marine science undergraduate student and Undergraduate Research Apprentice Program (URAP) intern, Ernesto Martinez conducted an optical survey of particulate organic carbon (POC) and particulate inorganic carbon (PIC) at from surface to seafloor at 26 locations along the 1600 km transect. Along the way he filtered particles from water samples to validate the new optical sensors.
PIC is produced by calcifying organisms, including coccolithophores, foraminifiera, and pteropods and plays an important role in carbon sedimentation. These organisms, which synthesize calcium carbonate minerals, are believed to be sensitive to the effects of fossil fuel acidification of the surface ocean but up to now scientists have had very few observations of PIC in the ocean.
A new ocean profiling optical sensor for PIC addresses this gap of observations. The sensor, developed in Professor Jim Bishop\'s laboratory, uses transmitted cross polarized light to detect photons that interact with biologically produced calcium carbonate minerals calcite and aragonite. This cruise is the first science application of Bishop\'s new PIC sensor. In 2013 Bishop\'s group will launch Carbon Explorer floats outfitted with POC and PIC sensors at PAPA which will operate in real time on a 24/7/365 schedule and return data to shore in real time.
Ernesto Martinez received a summer URAP internship for this work which is also supported by the National Science Foundation. Dr. Marie Robert, of the Institute of Ocean Sciences, BC, Canada led the expedition. WETLabs, Inc. Philomath, OR is our industrial partner on this project.