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Pteropods, also called sea butterflies, are tiny snails living in the water column that play a critical role in various ecosystems as prey for a variety of predators. There is a great concern about the potential impact of global change – and particularly ocean acidification – on these organisms as they exhibit an external shell, which is sensitive to changes in ocean chemistry. To represent the impact of both ocean acidification and global warming on pteropods, risk indicators have been calculated for three widely spread taxa that are dominant in high latitudes (Limacina helicina), temperate (Limacina retroversa), and warm waters (Creseis spp.). To create the indicators, experimental and observational data on pteropods’ response to global change were coupled with models describing chemical (aragonite saturation state) and physical (temperature) conditions of the ocean at present, in 2030 and 2050, under the “business as usual” carbon dioxide (CO2) emission scenario (RCP 8.5) and the “two degree stabilization” CO2 emission scenario (RCP 4.5). The present results confirm that global change is a very serious threat for high latitude pteropods: by 2050 under the CO2 emissions scenario RCP 8.5, they likely will not be able to thrive in most of the Arctic Ocean and some regions of the Southern Ocean.