Changes in the Arctic atmosphere, cryosphere and Ocean are drastically altering the dynamics of phytoplankton, the base of marine ecosystems. This Review addresses four major complementary questions of ongoing Arctic Ocean changes and associated impacts on phytoplankton productivity, phenology and assemblage composition. We highlight trends in primary production over the last two decades while considering how multiple environmental drivers shape Arctic biogeography. Further, we consider changes to Arctic phenology by borealization and hidden under-ice blooms, and how the diversity of phytoplankton assemblages might evolve in a novel Arctic ‘biogeochemical landscape’. It is critical to understand these aspects of changing Arctic phytoplankton dynamics as they exert pressure on marine Arctic ecosystems in addition to direct effects from rapid environmental changes.

北极大气，冰冻圈和海洋的变化极大地改变了海洋生态系统基础浮游植物的动态。本评论探讨了北冰洋持续变化及其对浮游植物生产力，物候和组合物组成的相关影响的四个主要补充问题。在考虑多种环境驱动因素如何塑造北极生物地理学的同时，我们着重介绍了过去二十年来初级生产的趋势。此外，我们考虑了北极化和冰层下暗藏花蕾对北极物候的变化，以及浮游植物组合的多样性如何在新颖的北极“生物地球化学景观”中演化。