Commentary on the outputs and future of Biogeochemical Exchange Processes at Sea-Ice Interfaces (BEPSII)

Abstract

Biogeochemical processes associated with sea ice are still inadequately described and poorly represented in models, making it difficult to properly quantify the impacts of climate change in polar regions. Within the framework of the international Scientific Committee of Ocean Research (SCOR) working group 140, BEPSII, a community of sea-ice biogeochemical scientists established guidelines for the measurement of biogeochemical processes in sea ice, collated observed data, synthesized knowledge of sea-ice biogeochemical processes, and identified the feedbacks between biogeochemical and physical processes at the terrestrial-ocean-ice-snow-atmosphere interfaces and within the sea-ice matrix. Many of these results are presented in Elementa’s Special Feature on BEPSII. By bringing together experimentalists and modelers, major improvements of sea-ice biochemistry models have been achieved which are anticipated to affect models on micro- to global scales. However, large gaps still exist in our understanding of detailed biogeochemical processes in sea ice, their seasonal evolution and their interactions with surrounding environments. The BEPSII community recommends continued focus on the development of reproducible methods and techniques for reliable inter-study comparisons, to enhance our understanding in areas where gaps have been identified via coordinated process studies combining modeling tools, laboratory experiments and field studies, and on the use of such studies to develop conceptual models helping us to understand the overall system.

Multi‐Model Intercomparison of the Pan‐Arctic Ice‐Algal Productivity on Seasonal, Interannual, and Decadal Timescales

“…Many uncertainties still remain with respect to ice‐algal model parameterizations, for example, photo‐acclimation, nutrient uptake, seeding to phytoplankton, zooplankton grazing pressure, and assemblage sinking speed (Steiner et al, ). International studies on sea‐ice biogeochemistry are progressing within the research community on Biogeochemical Exchange Processes at the Sea‐Ice Interfaces (BEPSII) (e.g., Steiner & Stefels, ) and on Measuring Essential Climate Variables in Sea Ice (ECV‐Ice). The physiological response to future climate changes may differ among a couple of functional algal groups (e.g., pennate diatom, centric diatom, flagellate, and sub‐ice strands) (van Leeuwe et al, ).…”

“…Many uncertainties still remain with respect to ice-algal model parameterizations, for example, photo-acclimation, nutrient uptake, seeding to phytoplankton, zooplankton grazing pressure, and assemblage sinking speed . International studies on sea-ice biogeochemistry are progressing within the research community on Biogeochemical Exchange Processes at the Sea-Ice Interfaces (BEPSII) (e.g., Steiner & Stefels, 2017)…”

Annual patterns in phytoplankton phenology in Antarctic coastal waters explained by environmental drivers

“…The Antarctic coastal zones belong to the most productive areas of the planet, and play a very important role in marine biogeochemical cycles (Arrigo et al 2017;Steiner and Stefels 2017). The Western Antarctic Peninsula (WAP) is such a hot spot for primary production.…”

Mapping the in situ microspatial distribution of ice algal biomass through hyperspectral imaging of sea-ice cores

“…In particular there is the lack of efficient methods capable of non-invasively tracking algal biomass across different scales, both vertically and horizontally, and concurrently with its physical drivers 11 , 12 . There is now evidence that variation in under-ice biophysical properties can range from the microscale (0.001 m 2 ) to the mesoscale (10 m 2 ) 13 – 15 , and this cannot be satisfactorily resolved using point-based sampling methods 16 , 17 .…”