Cal Poly Ocean Carbon Lab
Long Term Monitoring
Cal Poly Pier Time-Series
This research produces the first regular carbonate chemistry data on the Central Coast of California. Currently monthly samples are collected and analyzed for pH, dissolved inorganic carbon, and pH. These data are interpreted in combination with ongoing co-located biological and physical characterizations.
This continued time series helps us evaluate local oceanographic variability, relationships, and trends with particular note of expected changes due to accelerating anthropogenic climate change.
Morro Bay Estuary
Morro Bay Estuary
Morro Bay is a small nationally-protected estuary, with seasonally-low fresh water inputs. Since 2007, it has experienced a significant loss of its biogenic habitat, the native seagrass, Zostera marina. Because seagrass photosynthesis decreases carbon dioxide and increases oxygen in the water column, the loss of seagrass has the potential to substantially change short-term biogeochemical variability & long-term carbon fluxes of an estuary.
We are monitoring the carbonate chemistry throughout the Bay to better characterize the local spatial and temporal variability and to understand the potential causes and effects of observed changes to the bay with seagrass loss and recovery.
Sampling Methods
Problems with measurements can occur when there are particulates in the seawater sample to be measured. The particle may interfere with an optical measurement, or dissolve and contribute improperly to an acid titration. Filtration is difficult because seawater pH, pCO2 and dissolved inorganic carbon content are all sensitive to gas exchange. I have developed a method for filtering these samples, without unduly exposing them to the atmosphere, and have proven that accurate measurement is possible post filtration.
Now, we are putting this method into practice, exploring different environments that may be susceptible to measurement interference, such as productive coasts and estuaries.
Ocean Acidification
Understanding the threat of ocean acidification to oceanic organisms is an important component of understanding our world's response to anthropogenic climate change. I've been lucky to work with many biologists studying a variety of organisms (mussels, abalone, oysters, snails, squid) with a variety of response questions. The ability to perform these types of experiments in the laboratory rests on the ability to control an aquarium at the desired environment, which is where my interests lie. I build systems capable of carefully controlling the carbon dioxide levels, oxygen levels, and temperature of a multi-tank system. This allows us to reproduce the typical environment that an organism lives in (even a varying one), and modify it as desired.
Instrument Development
Increasing Efficiency, Quantity and Accessibility of Ocean Monitoring
In addition to monitoring local environments, our research focuses on improving and building instruments to measure pH, dissolved inorganic carbon, and total alkalinity in remote regions at a lower cost.
We develop instruments that measure carbonate parameters directly in the field. This allows us to promote community science, increase available oceanographic data, and reduce error from transporting discrete samples to the laboratory for analysis.
Listed below are a few of our current instrument projects.
pHyter
The pHyter is a hand held in situ pH measuring device that was designed by William Pardis, a previous student of Dr. Long's at Flathead Valley Community College in Montana. Their work was done in collaboration with Sunburst Sensors. This was a milestone achievement that helped increase community engagement and awareness about ocean acidification and carbonate chemistry.
Current work is focused on assessment of the pHyter, its applications, and how to improve its technology for a wide variety of users.
Poly Pod pH
Poly Pod pH builds on the concept of the pHyter and aims to improve the accessibility of field chemistry. It will be submergible to increase accuracy of spectrophotometric pH measurements by allowing for temperature equilibration with surrounding seawater.
Prototypes use an unconventional approach to absorbance spectroscopy to reduce the use of expensive single wavelength LED lights.
DICito
DICito is a portable dissolved inorganic carbon instrument intended to increase in situ non dispersive infrared analysis of DIC in remote field locations. This instrument was designed to reduce the costs associated with ocean monitoring and increase DIC data collection globally.
DICito was used to analyze seawater samples on our study abroad trip to French Polynesia (2026). This allowed for some of the first ever DIC data to be collected in Tetiaroa!
Current work on DICito aims to increase its portability to allow for collection of faster field measurements.
