2019-20 Honours project - Environmental Drivers of Antarctic Landfast Sea Ice Formation and Breakout

Antarctic Landfast sea ice (fast ice) is important climatologically, biologically and for logistics for short time-scale anomalies. Until recently, there hasn’t been an accurate, high-resolution fast ice extent dataset which can support an analysis on drivers of fast ice and most studies only investigate fast ice on limited regions of Antarctica in a limited time scale. There is a need to extend the spatial and temporal studying coverage to provide detailed information on the Antarctic coast over a longer period. This is the first detailed analysis to identify and quantify correlation between the environmental anomaly and fast ice anomaly mainly in the east Antarctic coast. By examining regional/local fast ice extent in in east Antarctic coast in the context of the broader and/or remote-teleconnected atmospheric circulation/properties using spatial correlation techniques, a strong correlation between NINO3 region and Lützow-Holm Bay fast ice and similar and significant correlation of regional scale factors from Lützow-Holm Bay to Mawson Coast mainly are found. The results of this thesis suggest that the pack ice, atmospheric factors and oceanic factors are important for interpreting fast ice anomalies. To identify and quantify correlation between the pack ice, temperature at 2m, wind at 10m, snow fall anomaly, sea surface temperature anomaly, ocean heat content anomaly and fast ice anomaly, backward multiple linear regression is conducted to demonstrate some predictive fast ice driver information by quantifying the correlation between different drivers and fast ice anomaly. The multiple linear regression also suggests that oceanic influences including pack ice are generally more important than atmospheric influences. Future experiments could be conducted to interpret fast ice anomalies in the context of the ocean mainly.

南极陆架固定海冰（fast ice）在气候学、生物学领域以及短时尺度异常的后勤保障工作中均具有重要意义。直至近期，尚无能够支撑固定冰驱动因子分析的高精度高分辨率固定冰范围数据集，且绝大多数现有研究仅针对南极有限区域开展了有限时间尺度内的固定冰研究。有必要拓展研究的时空覆盖范围，以在更长时间尺度上提供南极沿岸区域的详细海冰信息。本研究首次针对南极东海岸区域开展系统性详细分析，旨在识别并量化环境异常与固定冰异常之间的关联关系。本研究借助空间相关性分析技术，结合大尺度乃至远程遥相关大气环流特征，对南极东海岸的局地/区域固定冰范围展开研究，结果发现尼诺3（NINO3）海区与吕佐夫-霍尔姆湾（Lützow-Holm Bay）固定冰之间存在显著相关性，同时在吕佐夫-霍尔姆湾至莫森海岸（Mawson Coast）区域也观测到了尺度相当的显著关联因子。本研究结果表明，浮冰群（pack ice）、大气因子与海洋因子均是解释固定冰异常的关键要素。为识别并量化浮冰群、2米气温、10米风速、降雪异常、海表温度异常、海洋热含量异常与固定冰异常之间的关联，本研究采用向后多元线性回归方法，通过量化各类驱动因子与固定冰异常之间的相关性，揭示了部分可用于预测固定冰异常的驱动因子信息。多元线性回归分析结果同样表明，包含浮冰群在内的海洋影响因子总体上较大气影响因子更为关键。未来可开展聚焦海洋要素的相关研究，以进一步阐释固定冰异常的形成机制。