Research

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.