EU project OCEAN:ICE Deliverable: D1.4 Gridded European circumpolar sea ice production fluxes

This deliverable is a new dataset of sea ice production (SIP) in Antarctic coastal polynyas, critical regions for sea ice formation and dense water formation. Using Earth Observation data and atmospheric reanalysis, we use a heat budget method to estimate the SIP. We use sea ice concentration (SIC) from passive microwave sensors and ECMWF ERA5 reanalysis for near-surface wind speed and surface air temperature. Comparison against previous literature shows broad consistency in spatial patterns and magnitude of ice production, with notable variations across larger polynyas. Despite simplifications and thereby increased uncertainties in the absolute ice production values, the data set provides valuable insights into the dynamics and variability of Antarctic polynya SIP for the period 1992-2023.

本交付成果为一套全新的南极沿岸冰间湖（Antarctic coastal polynyas）海冰生成量（Sea Ice Production, SIP）数据集，而冰间湖是海冰形成与高密度水形成的关键区域。本研究借助地球观测（Earth Observation）数据与大气再分析资料，采用热量收支法对海冰生成量进行估算。我们采用被动微波传感器（passive microwave sensors）获取的海冰密集度（Sea Ice Concentration, SIC），以及欧洲中期天气预报中心（ECMWF）ERA5再分析资料来获取近地表风速与地表气温数据。与已有文献的对比结果表明，该数据集在海冰生成的空间分布格局与数值量级上整体吻合度较高，但在大型冰间湖区域存在显著差异。尽管本数据集采用了简化假设，导致绝对海冰生成量的估算不确定性有所提升，但它仍为1992年至2023年期间南极冰间湖海冰生成的动力学过程与年际变率提供了极具价值的研究视角。