Photo Caption/Credit: The new buoy measuring ocean acidification parameters in the mouth of the Chesapeake Bay. Credit: Doug Wilson, MARACOOS Board Member, Caribbean Wind LLC
A yellow buoy now sits where the vast open ocean meets freshwater from six different states. Why? To understand acidification in the largest estuary in the United States- the Chesapeake Bay. “This is the first buoy measuring carbon dioxide (CO2) long-term in the Chesapeake Bay” says Dr. Wei-Jun Cai, professor at University of Delaware.
In recent summers, researchers aboard the University of Delaware’s vessel Hugh R. Sharp worked to identify areas of the Bay that may be vulnerable to excess inputs of CO2 . It seems the Chesapeake Bay has a low buffering capacity, or ability to keep a stable pH (a measure of the For Official Use Only-Pre-decisional Deliberative Information-Not for Public Release acidity of the water), during large fluctuations of CO2 . Just like adding Old Bay to a shrimp boil, if too much is added, it can be difficult to remove.
“High nutrient input from wastewater treatment plants; urban, suburban and agricultural runoff; and air pollution, appear to lower the buffering capacity of the Chesapeake Bay, making it particularly vulnerable to swings in pH” said Dr. Jeremy Testa, professor at University of Maryland Center for Environmental Science.
In carbon-dioxide rich waters, research has shown that young shellfish, such as the economically important Eastern oysters, can have difficulty growing and surviving. “Although ocean acidification does not seem to be a primary concern for oyster aquaculture in this region right now, this newly deployed buoy will supply models with the needed information to recognize potential susceptible areas and what future chemical parameters, like CO2 and buffering capacity, may look like in the Bay” said Dr. Testa.
Why here? Why now? “Early on in the NOAA Ocean Acidification Observing Network, we did an assessment of the existing research and observations, and the Chesapeake Bay was a region where we were clearly lacking information” says Dr. Adrienne Sutton, an oceanographer at NOAA’s Pacific Marine Environmental Laboratory (PMEL). “This buoy will be placed in the mouth of the bay to help us understand the complex interface between freshwater rivers and the open ocean” says Sutton. The chemistry in large estuaries like the Chesapeake Bay goes through sizable natural variations, which make it difficult to identify human driven changes in chemistry. A buoy at this interface will help scientists monitor Bay chemistry over days to years, and differentiate human impact from natural variations.
The goal of this partnership between NOAA Ocean Acidification Program (OAP), NOAA PMEL, U.S. IOOS Mid-Atlantic Regional Association Coastal Ocean Observing System (MARACOOS), and the University of Delaware (UDel) is to produce high quality data and models to monitor the Chesapeake Bay. The new buoy is located beside the First Landing Chesapeake Bay Interpretive Buoy System (CBIBS) site to maximize collaborations with existing research and observational efforts, leverage equipment assets, and integrate with ongoing ship-based surveys and outreach activities.
Dr. Testa will use the buoy measurements to inform a model he and other researchers created to address ocean acidification in the Chesapeake Bay. “The big advantage of this model is that it allows us to simulate what we think is changing from day to day and season to season,” says Testa. “The buoy data will help confirm how well the model is performing”. The model can be used to predict how much CO2 these waters absorb from the atmosphere and how much the Bay’s acidity will change in the future.
The buoy will relay information daily to NOAA PMEL. There, Dr. Sutton will manage the data stream and ensure consistent quality of measurements across the NOAA’s National Ocean Acidification Observing network,so that comparisons can be made between different coastal regions of the U.S.. This real-time data can be viewed on the following websites: CBIBS, NOAA PMEL, and MARACOOS.
This information will illuminate if and how the Chesapeake Bay will buffer against changes with
the added “spice” of excess carbon dioxide. It is a key to advancing our understanding of the
drivers behind acidification and susceptibility of this important estuary to acidification, and the
communities tied to it.