Climate change and Ocean Acidification (OA) are two of the largest threats to oceans today.
Determining where to place conservation areas that will protect the ocean now, and as it changes into the future, requires an understanding of how these threats will alter ocean ecosystems, and what uses humans place on, for example fisheries or energy production, in each region. Despite us recognising this however, studies addressing these elements together are still lacking.
In a new study, PML scientists sought to fill these gaps in knowledge through the combined analysis of a large number of mathematical models which focused on the impact of climate change for low and high foodweb levels and human uses, focusing on the NE Atlantic region.
Using a novel method, the scientists were able to determine where the ocean ecosystem will change as a whole due to climate change and ocean acidification by the middle of the 21st century. Also, by combining this analysis with the current (and foreseen) distribution of Marine Protected Areas, (MPAs) and windfarms in the region, the team were able to conclude whether these current conservation plans would actually protect the ocean against these changes, into the future.
A second innovation of the study was that the team considered explicitly, in their analysis, the changes at the very bottom of the marine food web triggered by climate change and OA, as well as those in species more traditionally considered in conservation plans, for example fish. This is because evidence from experimental studies in climate change has shown that the survival of animals experiencing environmental change (like warming and ocean acidification) requires the reliable availability of food resources like plankton at the base of the marine food web in order to support the stress processes that these changes trigger, as well as other standard processes involved in species survival, like the generation of offspring.
The study found that whilst in many areas MPAs are currently placed in regions of the NE Atlantic that will not change significantly due to climate and acidification, however many other areas that will change are not currently foreseen in MPA design for the region. These include new habitats the scientists identified as areas where species will move to as climate change and acidification unfold, as well as some of the most productive areas of the NE Atlantic. This means that regions that may become fundamental habitat shelters for ocean species (and the ecosystem as a whole) in the near future, as climate change and OA develop, are currently open and vulnerable to other pressures such as fisheries and wind farms.
Through these findings this study aims to inform the positioning MPAs with consideration for how climate change and ocean acidification will modify the structure of ocean systems over time, in order to create better conservation plans to protect our changing oceans now, and in the future.