Earth and Planetary Science
EPS Near-Surface Geochemistry and Geobiology

Berkeley's Carbon Flux Explorers Gain New Key to Poseidon's Carbon Secrets

Thursday, March 28, 2019

Ocean Phytoplankton live for a week before they are eaten, yet this process is the start of a strong transport of sinking organic matter into the deep sea and fosters ocean uptake of atmospheric CO2. So little is known about the fast process of this so-called the Biological carbon pump due to reliance on ships. Berkeley's Carbon Flux Explorers are deep diving autonomous systems designed to measure the hourly variations of the sinking rates of particulate organic matter to kilometer depths and to transmit data in real time to satellites for missions as long as one year. CFE's use transmitted light imaging to quantify the accumulation rate of particles; we needed to calibrate this proxy for particle flux.

Dr. Hannah Bourne (EPS PhD, 2018) has published the first study documenting the strongly correlated relationship of the CFE's optical particle flux proxy with measured carbon and nitrogen flux. In other words, Hannah's work has put the letters C and N into CarboN Flux Explorer. Dr. Bourne's study with EPS Prof. Bishop, LBNL Engineers Todd Wood and Tim Loew and undergraduate engineerig student Yizhuang Liu was funded by the National Science Foundation. It required the design and integration of an entirely new particle sampling system with the CFE. The system - constructed mostly from 3D printed parts fabricated in Jacobs Hall - went from design to the ocean in less than one month. The study took which took place in California coastal waters in August 2016 R/V Oceanus (photo by Jessica Kendall-Bar) and June 2017 aboard R/V Revelle.