Brief communication: Intercomparison study reveals pathways for improving the representation of sea-ice biogeochemistry in models

Abstract. Sea-ice biogeochemical models are key to understanding polar marine ecosystems. We present an intercomparison of six one-dimensional sea-ice biogeochemical models, assessing their ability to simulate algal phenology and nutrient dynamics by comparing them with sea-ice physical-biogeochemical data collected during the N-ICE2015 expedition. While no model fully captured observed bloom dynamics without tuning, adjustments improved biomass simulations but had a limited impact on nutrient representation. Variability in tuning strategies underscores key knowledge gaps and the need for further model development in more harmonised ways. Our findings can inform future efforts to enhance the reliability and predictive capacity of sea-ice biogeochemical models.