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Research Fellowships

Drivers and Impacts of Coastal Acidification in Pacific Northwest Estuaries

EPA Office of Research and Development

EPA National Science Foundation Graduate Research Internship Program (GRIP) & Graduate Research Fellowship Program (GRFP) Opportunities

Opportunity Title:

Drivers and Impacts of Coastal Acidification in Pacific Northwest Estuaries

Research Area:


EPA Lab/Center/Office:

National Health and Environmental Effects Research Laboratory (NHEERL)


Newport, OR


3 - 12 months

Brief Summary:

The intern selected for this position would develop a project focused on the role of eutrophication in influencing coastal acidification and the impact of this acidification on estuarine ecosystems.  

Opportunity Description:

Carbon dioxide levels are causing a decline in oceanic pH, which is impacting marine ecosystems. In coastal and estuarine waters, this acidification may be exacerbated by local processes such as atmospheric emissions, and point and nonpoint nutrient inputs.  EPA has encouraged States to assess whether their waters are impaired due to acidification and incorporate acidification into their listing process. A key need are tools to distinguish causes of acidification in coastal and estuarine waters and effects-based research. The intern selected for this position will contribute to field and lab based studies focused on identifying the causes and impacts of acidification in Pacific Northwest estuaries. Research opportunities could either be based on field studies focused in Oregon estuaries or laboratory mesocosm studies.

Our laboratory is currently conducting a suite of complementary field studies focused in the Tillamook Estuary. As part of this effort, we are focused on quantifying the role of local factors on carbonate chemistry dynamics in this system. We are sampling the tributaries entering Tillamook Estuary for nutrients, natural abundance stable isotopes (dissolved inorganic nitrogen and carbon, and particulate matter), and carbonate chemistry, as well as deploying in-situ carbonate chemistry monitoring instrumentation in the estuary. Laboratory mesocosm studies are focused on the effect of nutrient enrichment and temperature on estuarine communities. We have a range of experimental systems at our laboratory ranging from 6 liter dual compartment chambers to 325 and 3200 liter mesocosms.  Mesocosm facilities at our laboratory allow us to evaluate effects of multiple stressors simultaneously, and are equipped with Honeywell Durafet pH sensors. Currently these mesocosms have the ability to control residence time, nutrient load, irradiance and temperature. In the future, we anticipate adding the capacity to manipulate mesocosm pCO2 levels. Other instrumentation available for use in field and laboratory studies include optical nitrate sensors (ISUS) as well as Sunburst SAMI pH and pCO2 sensors, Shimadzu Total organic carbon analyzer, and a dual pCO2/TCO2 analyzer for carbonate chemistry. 

The successful intern would develop a complementary project embedded within either the field studies or mesocosm experiments. Possible topics may include incorporating an organismal-effects-based component, assessment of impairment associated with organic nutrients, alterations of biogeochemical processing (e.g. ecosystem metabolism, carbon accumulation), or systems modeling. Other ideas are also welcome.

Opportunities for Professional Development:

Professional development opportunities will include being a member of diverse research team working on coastal acidification and mentoring on how science can be used to inform management decisions. Depending upon the intern project, training opportunities may include training on state-of-the-art carbonate chemistry measuring systems and conducting mesocosm experiments. This intern will be at Hatfield Marine Science Center (HMSC), which is a consortium of university, federal and state agencies. The HMSC community provides many professional development opportunities, including seminar series, training and volunteer opportunities, and the ability to interact with diverse research and management community.

Point of Contact or Mentor:

Cheryl Brown (

For more information about EPA Research Fellowship opportunities, visit: