Natural adaptation to climate change in ocean and coastal systems includes an array of responses taking place at scales from cells to ecosystems. Previous IPCC assessments have established that many marine species 'have shifted their geographic ranges, seasonal activities, migration patterns, abundances and species interactions in response to climate change'  , which has had global impacts on species composition, abundance and biomass, and on ecosystem structure and function  . Warming and acidification have affected coastal ecosystems in concert with non-climate drivers , which have affected habitat area, biodiversity, ecosystem function and services  . Confidence has grown in these assessments over time as observational datasets have lengthened and other lines of evidence have corroborated observations. AR5 and SROCC assessed how physiological sensitivity to climate-induced drivers is the underlying cause of most marine organisms' vulnerability to climate  . Since those assessments, more evidence supports the empirical physiological models of tolerance and plasticity  and of interactions among multiple  drivers at individual to ecosystem scales . New experimental evidence about evolutionary adaptation  bolsters previous assessments that adaptation options to climate change are limited for eukaryotic organisms. Tools such as ecosystem models can now constrain probable ecosystem states . Observations have increased understanding of how extreme events affect individuals, populations and ecosystems, helping refine understanding of both ecological tolerance to climate impacts and ecological transformations .
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report