The Mid-Atlantic Coastal Acidification Network (MACAN): Utilizing the Mid-Atlantic Ocean Data Portal to Identify Monitoring Gaps for Regional Ocean and Coastal Acidification

The quickly rising levels of carbon dioxide (CO₂) in the atmosphere are leading to ocean acidification (OA), as the oceans absorb this excess CO₂. The Mid-Atlantic, the most densely urbanized region in the United States, may be especially vulnerable to acidification in coastal waters, where high nutrient levels from developed areas act to further reduce pH and exacerbate OA. The Mid-Atlantic Coastal Acidification Network (MACAN) seeks to help coastal communities and industries understand and plan for the impacts of acidification. Toward this end, MACAN coordinated with the Mid-Atlantic Ocean Data Portal (Portal) to develop a series of acidification monitoring maps that show the locations of past and present acidification monitoring in the Mid-Atlantic. A MACAN working group then used the maps to identify potential monitoring gaps, which included: a) Sampling frequency is too low to adequately capture short-term episodic events and seasonal variability; b) Lack of multiple carbonate system parameters measured to allow full characterization of acidification; and c) Lack of sampling in subsurface waters. To address these gaps, MACAN recommended several regional monitoring priorities and has been working actively with the wider community through workshops and supporting new research projects to make progress toward optimizing regional acidification monitoring efforts.