Short-term forecasting method for prevailing orientation of leads in the Laptev Sea ice cover during winter-spring season

• Main Authors: L. N. Dyment, A. A. Ershova, V. S. Porubaev, Л. Н. Дымент, А. А. Ершова, В. С. Порубаев
• Other Authors: The research was carried out within the framework of the scientific research and technology works 5.1.1 of Roshydromet for 2020–2024. “Development of models, methods and technologies for monitoring and forecasting the state of the atmosphere, ocean, sea ice cover, glaciers and permafrost (cryosphere), processes of interaction of ice with natural objects and engineering structures for the Arctic and technologies for hydrometeorological provision of consumers”., Исследования выполнены в рамках НИТР 5.1.1 Росгидромета на 2020–2024 гг. «Развитие моделей, методов и технологий мониторинга и прогнозирования состояния атмосферы, океана, морского ледяного покрова, ледников и вечной мерзлоты (криосферы), процессов взаимодействия льда с природными объектами и инженерными сооружениями для Арктики и технологий гидрометеорологического обеспечения потребителей».
• Format: Article in Journal/Newspaper
• Language: Russian
• Published: Государственный научный центр Российской Федерации Арктический и антарктический научно-исследовательский институт 2024
• Subjects: эллипс деформации; analog method; forecast verification; ice discontinuities; ice drift; modal orientation; satellite images; strain ellipse; дрейф льда; метод аналогов; модальная ориентация; нарушения сплошности льда; оправдываемость прогноза; спутниковые снимки; Annals of Glaciology; Arctic; laptev; Laptev Sea; Sea ice
• Online Access: https://www.aaresearch.science/jour/article/view/595; https://doi.org/10.30758/0555-2648-2024-70-1-87-102

Sea ice leads are potential routes of easier navigation in the Arctic seas during winter-spring season. Forecasts of the prevailing orientation of ice leads are required for the early selection of the optimal route of a ship in ice. An automated method for short-term forecasting of the prevailing orientation of leads in the Laptev Sea is developed in AARI based on the analog method. Data sources for making a forecast include predictive fields of atmospheric pressure up to 3 days in advance and historical data on surface atmospheric pressure, ice drift and sea ice leads. The data on ice leads are obtained by interpreting SuomiNPP satellite images in a visible and infrared range at 375 m spatial resolution for the cold seasons 2016–2022. The ice drift data are freely available OSI SAF data. In order to make a forecast of the prevailing orientation of leads by a predictive atmospheric pressure field, it is necessary to select from an electronic data archive a historical field of atmospheric pressure that is the most similar to the predictive field. The lead characteristics on the selected date are taken as the predictive ones. Automated selection of an analog consists in searching for an atmospheric pressure field from the electronic data archive which has minimal metrics for the forecast date together with 2 previous days. The metric is calculated as the sum of the squared differences between the change in atmospheric pressure per 1 km in the latitudinal and meridional directions between the predictive atmospheric pressure field and the potential analog field. Actual lead data for a date of the selected analog may not be available due to thick clouds. In this case, the direction of the minor axis of the strain ellipse calculated from ice drift data is taken as the prevailing orientation of leads. The success ratio of diagnostic forecasts by the method developed is 72 %. Comparison of the success ratio of the diagnostic forecasts with the results of inertial and climatic forecasts demonstrates a high effectiveness ...