OPP-PRF: The predictive capacity of ocean heat gain and autumn freeze up dates on seasonal sea ice extent from three reanalyses and the CESM2 Large Ensemble

该项目的重点是提高北极海冰范围的可预测性。这项研究将利用大量模拟中免费提供的数据，利用海洋热量模式来评估秋季海冰冻结的时间与季节性可预测性的关系。研究人员希望该项目通过应用统计数据来评估哪些环境变量对海冰损失最重要，从而为了解北冰洋海冰变化的环境影响做出重大贡献。在过去的40年里，海冰在所有月份都在减少，留下了更薄更小的浮冰，由于气候变暖，这种变化预计将继续下去。这些变化不仅会产生气候影响，还会产生经济影响，这就是为什么准确预测季节尺度上的海冰范围很重要。随着北极失去海冰覆盖，航运和资源开采变得更加容易，但对依赖冰的土著社区和受威胁物种来说也不那么可靠。海冰可以长到几米厚，导致北极地区无法通行，除非该实体可以使用破冰船。更好地了解导致海冰变化的因素将改善模型并告知公众，以便他们能够更有效地进行规划。该项目旨在吸引少数群体的参与，并鼓励不同教育水平的人们对北极气候有更深入的科学了解。这将通过为高中和初中学生创建一个名为“数据拼图”的短期课程（https：//datapuzzles.org/）并雇用一名本科实习生来完成。虽然影响北极海冰损失的基本物理过程得到了很好的认识，但关于季节性北冰洋热量吸收和释放的幅度、变化和趋势的定量信息很少。该项目将结合新提供的社区地球系统模型第2版大型Ensemble（CESM 2-LE）的输出，对三个回顾性模型的海洋得热数据进行新的利用。使用来自综合被动微波海冰记录的海冰浓度（SIC）数据，将计算每个网格单元的开放水域总天数，以评估开放水域天数和秋季冻结日期的变化和变化。最后，将使用季节性自回归综合移动平均模型（SARIMA）预测提前一个月、两个月和三个月的季节性SIC。在多变量模型中，将使用总海洋得热、平均云量、总水柱和开放水域天数作为预测因子。研究人员将使用统计模型来估计各种北极气候特征对海冰范围和未来季节预测的影响。该项目将大大有助于了解北极气候和帮助改进模型。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。

This project focuses on improving sea ice extent predictability in the Arctic. Using freely available data from a number of simulations, this research will use ocean heat patterns to assess how the timing of autumn sea ice freeze up relates to seasonal predictability. The researcher expects this project to contribute significantly to the understanding of environmental influences on sea ice change across the Arctic Ocean, by applying statistics to evaluate which environmental variables are the most significant for sea ice loss. Over the last 40 years, sea ice has declined in all months, leaving thinner and smaller sea ice floes, and such changes are expected to continue due to climate warming. These changes produce not only climate impacts, but also economic impacts, which is why accurately forecasting sea ice extent on seasonal scales is important. As the Arctic loses sea ice cover, it becomes more accessible to shipping and resource extraction but also less reliable for Indigenous communities and threatened species that depend on the ice. Sea ice can grow to be multiple meters thick causing regions of the Arctic to be impassible, unless the entity has access to an icebreaker ship. Better knowing the factors contributing to sea ice change will improve models and inform the public so they can plan more efficiently. This project aims to engage minority groups and encourage the development of greater scientific understanding of the Arctic climate for people at many educational levels. This will be done by creating a short course for high school and middle school students called a Data Puzzle (https://datapuzzles.org/) and employing an undergraduate intern. While basic physical processes impacting sea ice loss in the Arctic are well recognized, little quantitative information exists on the magnitudes, variability, and trends in seasonal Arctic Ocean heat uptake and release. This project will make novel use of ocean heat gain data from three retrospective models in conjunction with output from the newly available Community Earth System Model version 2 Large Ensemble (CESM2-LE). Using sea ice concentration (SIC) data from the combined Passive Microwave sea ice record, the total days with open water at each grid cell will be calculated to assess how open water days and the date of autumn freeze up have varied and changed. Lastly, a seasonal autoregressive integrated moving average model (SARIMA) will be used to predict seasonal SIC at lead times of one, two and three months. Total ocean heat gain, average cloud cover, total column water, and number of open water days will be used as predictors in the multivariate model. The researcher will use statistical models to estimate the influence of various Arctic climate characteristics on sea ice extent and future seasonal predictions. This project will significantly contribute to the understanding of the Arctic climate and aid in model improvement.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.