Impact of horizontal resolution on global ocean-sea-ice model simulations based on the experimental protocols of the Ocean Model Intercomparison Project phase 2 (OMIP-2)

Datasets for the Geoscientific Model Development publication: "Impact of horizontal resolution on global ocean-sea-ice model simulations based on the experimental protocols of the Ocean Model Intercomparison Project phase 2 (OMIP-2)" Abstract: This paper presents global comparisons of fundamental global climate variables from a suite of four pairs of matched low- and high-resolution ocean and sea-ice simulations that are obtained following the OMIP-2 protocol (Griffies et al., 2016) and integrated for one cycle (1958-2018) of the JRA55-do atmospheric state and runoff dataset (Tsujino et al., 2018). Our goal is to assess the robustness of climate-relevant improvements in ocean simulations (mean and variability) associated with moving from coarse (~1º) to eddy-resolving (~0.1º) horizontal resolutions. The models are diverse in their numerics and parameterizations, but each low-resolution and high-resolution pair of models is matched so as to isolate, to the 20 extent possible, the effects of horizontal resolution. A variety of observational datasets are used to assess the fidelity of simulated temperature and salinity, sea surface height, kinetic energy, heat and volume transports, and sea ice distribution. This paper provides a crucial benchmark for future studies comparing and improving different schemes in any of the models used in this study or similar ones. The biases in the low-resolution simulations are familiar and their gross features – position, strength, and variability of western boundary currents, equatorial currents, and Antarctic Circumpolar Current – are 25 significantly improved in the high-resolution models. However, despite the fact that the high-resolution models “resolve’’ most of these features, the improvements in temperature or salinity are inconsistent among the different model families and some regions show increased bias over their low-resolution counterparts. Greatly enhanced horizontal resolution does not deliver unambiguous bias improvement in all regions for all models.用于《地球科学模式发展》（Geoscientific Model Development）期刊发表论文的配套数据集：《基于海洋模式比对计划第二阶段（Ocean Model Intercomparison Project phase 2, OMIP-2）实验规程的水平分辨率对全球海洋-海冰模式模拟的影响》 摘要：本研究针对四组匹配的高低分辨率海洋与海冰模拟试验对，基于海洋模式比对计划第二阶段（OMIP-2）规程（Griffies等，2016）开展，以JRA55-do大气状态与径流数据集（Tsujino等，2018）1958-2018年完整周期作为强迫场进行积分，进而对核心全球气候变量开展全球尺度对比分析。本研究的核心目标为评估：当海洋模式水平分辨率从粗分辨（约1°）提升至涡旋分辨尺度（约0.1°）时，海洋模拟（平均态与变率）中与气候相关的改善效果的稳健性。参与试验的各模式在数值方法与参数化方案上存在显著差异，但每一组高低分辨率模式对均经过严格匹配，从而尽可能剥离其他因素的干扰，单独分析水平分辨率的影响。本研究采用多套观测数据集，对模拟得到的温度、盐度、海表高度、动能、热与体积输送以及海冰分布的模拟保真度进行评估。本数据集可为未来针对本研究所用模式或同类模式中不同方案的对比与优化研究提供关键基准参考。粗分辨率模拟中存在的偏差特征为学界所熟知，而高分辨率模式对西边界流、赤道流与南极绕极流的位置、强度及变率等宏观特征的模拟精度均得到显著提升。尽管高分辨率模式能够解析绝大多数上述海洋特征，但不同模式家族间，温度与盐度模拟的改善效果并不一致，部分区域的高分辨率模拟偏差甚至较粗分辨率试验更为显著。大幅提升水平分辨率并不能保证所有模式在所有区域的模拟偏差都得到明确改善。