Novel Ocean Futures: Anticipating Great Change in the World's Marine Protected Areas

Abstract

Climate change has far-reaching implications for the continued utility of marine protected areas (MPAs) as the ocean's biogeochemistry is altered. We employed an application of information theory to measure the departure from historical conditions of six key marine biogeochemical variables for all parts of the ocean and the largest MPAs. We analyzed a multi-model ensemble (CMIP6) under three climate change scenarios and found that between 76-97% of the largest MPAs will exhibit significant departures from current conditions in their biogeochemical profiles, with most novel conditions emerging as soon as the 2030s (pH) and most others by 2060. These results suggest that many of the largest MPAs will contain environmental conditions unlike those currently within their boundaries, and, given the likelihood of any of these climate futures unfolding, present-day management may need to consider alterations to current and future MPA planning.