Understanding the consequences of rising CO2 and warming on marine ecosystems is a pressing issue in ecology. Manipulative experiments that assess responses of biota to future ocean warming and acidification conditions form a necessary basis for
expectations on how marine taxa may respond. Although designing experiments in the context of local variability is most
appropriate, local temperature and CO2 characteristics are often unknown as such measures necessitate significant resources,
and even less is known about local future scenarios. To help address these issues, we summarize current uncertainties in CO2
emission trajectories and climate sensitivity, examine regionspecific changes in the ocean, and present a straightforward global framework to guide experimental designs. We advocate for the inclusion of multiple plausible future scenarios of predicted levels of ocean warming and acidification in forthcoming experimental research. Growing a robust experimental base is crucial to understanding the prospect form
and function of marine ecosystems in the Anthropocene.