Novel environmental conditions due to climate change in the world's largest marine protected areas

Abstract

•Up to 97% of very large marine protected areas will contain novel conditions •Very large marine protected areas in the tropics most exposed to novelty •Novel conditions for pH emerge as soon as 2030 •44.9% of the ocean will see novel conditions by 2060, up to 87% by 2100 Climate change is altering the biogeochemical conditions of the ocean, leading to the emergence of novel environmental conditions that may drastically affect the performance of very large marine protected areas (VLMPAs) (area > 100,000 km2). Given the prominent role that VLMPAs play in ocean conservation, determining when and where novel conditions will emerge within VLMPAs is vital for ensuring a healthy ocean in the future. Here, using a non-parametric approach to detect novelty, we show that 60%–87% of the ocean and 76%–97% of VLMPAs are expected to contain novel conditions across multiple biogeochemical variables by 2100, with novel conditions in pH emerging by 2030. With most VLMPAs expected to contain environmental conditions unlike those currently within their boundaries, and given the likelihood of any of these climate futures unfolding, present-day management will need to consider alterations to current and future VLMPA design and use. Climate change is altering the biogeochemical conditions of the ocean, leading to the emergence of novel environmental conditions that may drastically affect the performance of very large marine protected areas (VLMPAs) (area > 100,000 km2). Given the prominent role that VLMPAs play in ocean conservation, determining when and where novel conditions will emerge within VLMPAs is vital for ensuring a healthy ocean in the future. Here, using a non-parametric approach to detect novelty, we show that 60%–87% of the ocean and 76%–97% of VLMPAs are expected to contain novel conditions across multiple biogeochemical variables by 2100, with novel conditions in pH emerging by 2030. With most VLMPAs expected to contain environmental conditions unlike those currently within their boundaries, and given the likelihood of any of these climate futures unfolding, present-day management will need to consider alterations to current and future VLMPA design and use.