Climate Change and Ocean Acidification
Monterey Bay

photo of an anemone with a kelp forest in the background
Global climate change and ocean acidification may impact “key” species such as kelp. Kelp provide important structural features and ecosystem function to coastal marine communities. Credit: Chad King, MBNMS, NOAA

Why is it a concern?

Monterey Bay National Marine Sanctuary is the second largest national marine sanctuary and among the larger marine protected areas in the United States. Global climate change is increasing sea surface temperatures – this increasing temperature combined with increasing concentrations of atmospheric carbon dioxide are causing the world’s oceans to become more acidic. Ocean chemistry is changing at a rapid pace, and by 2100 it is predicted to drop an additional 0.3 pH units and become more acidic. Other impacts from climate change to sanctuary resources include larger and more frequent storms, increased coastal erosion, higher rates of coastal inundation, and a greater threat of saltwater intrusion.

Climate change can also exacerbate other issues within the sanctuary. For example increased sea surface temperature in combination with runoff, sewage, and fertilizers may be interacting to alter the natural pattern of algal blooms, altering their frequency, spatial extent, species composition, and toxicity.

Overview of Research

Project Name PI and contacts Links

Ocean Margin Ecosystems Group for Acidification Studies

Multiple PIs See website

Nearshore water monitoring of oxygen and pH in southern Monterey Bay

J. Ashley Booth, Curtis Deutsch, Brock Woodson

Ocean observing in the Monterey Bay National Marine Sanctuary: CalCOFI and the MBARI time series

Francisco Chavez and Timothy Pennington


photo of a house on a cliff showing erosion
Global climate change may lead to more severe storms with larger waves which may in turn accelerate coastal erosion. Credit: NOAA

Science Needs and Questions

  • What are the human carbon inputs to the sanctuary?

  • What is the net carbon budget for the sanctuary?

  • What is the spatial extent of the aragonite solubility surface and how is that changing?

  • How would sea level change affect sanctuary resources with coastal armoring?

  • How will changes in ocean chemistry affect mussel beds and key planktonic forage species?

Education and Outreach Material

Understanding Ocean Acidification


Doney, S.C. 2006. The dangers of ocean acidification. Scientific American 294(3):58-65.

Gilbert, P.M., S. Seitzinger, C.A. Heil, J.M. Burkholder, M.W. Parrow, L.A. Codispoti, V. Kelly. 2005. The role of eutrophication in the global proliferation of harmful algal blooms: new perspectives and new approaches. Oceanography 18:198-209.