This proposal focuses on collecting and analyzing 13C-DIC samples on the east coast ocean acidification cruise (ecoa) to estimate decadal decreases in 13C-DIC and increases in anthropogenic CO2…

The University of Delaware received a $150,000 cooperative agreement award from the National Oceanic and Atmospheric Administration (NOAA) under the Ocean Acidification Program (OAP, CFDA 11.017), effective September 1, 2025, through August 31, 2028. The institution will collect and analyze carbon-13 dissolved inorganic carbon (13C-DIC) samples during the East Coast Ocean Acidification cruise to quantify decadal decreases in 13C-DIC and track increases in anthropogenic carbon dioxide accumulation rates using extended multiple linear regression methodology.

The project deliverables include high spatial resolution 13C-DIC data collection compared against baseline samples from 2018, 2022, and historical 1996 cruise data to assess the influence of atmospheric history and lateral carbon transfer on anthropogenic CO2 accumulation rates. Additionally, the 13C-DIC analysis will partition carbon sources and identify the physical and biological drivers of subsurface ocean acidification. These research products directly support NOAA's mission to enhance understanding of ocean acidification impacts on marine ecosystems and provide actionable scientific information for coastal resource management.

This proposal focuses on collecting and analyzing 13C-DIC samples on the east coast ocean acidification cruise (ecoa) to estimate decadal decreases in 13C-DIC and increases in anthropogenic CO2 accumulation rates using an extended multiple linear regression method. The objectives of the work are to collect high spatial resolution 13C-DIC data and compare IT to 2018 and 2022 cruise samples, along with 1996 bauer ET AL. Samples, to gauge the influence of atmospheric history and lateral transfer on anthropogenic CO2 accumulation; and to use 13C-DIC to partition the carbon sources and understand physical & biological drivers of subsurface OA.