Change in the time of stable ice formation in the Russian Eastern Arctic seas at the beginning of 21st century

• Published in: Arctic and Antarctic Research
• Main Authors: A. Egorov G., E. Pavlova A., А. Егоров Г., Е. Павлова А.
• Format: Article in Journal/Newspaper
• Language: Russian
• Published: Государственный научный центр Российской Федерации Арктический и антарктический научно-исследовательский институт 2019
• Subjects: autumn period; ice cover of the Russian Arctic seas; multi-year variations; the Chukchi sea; the Laptev sea; the East-Siberian sea; time of stable ice formation; Восточно-Сибирское море; ледяной покров арктических морей России; многолетняя изменчивость ледовых условий; море Лаптевых; срок устойчивого ледообразования; позднее ледообразование; Чукотское море; Arctic; Chukchi Sea; East Siberian Sea; Laptev Sea; Chukchi; laptev
• Online Access: https://www.aaresearch.science/jour/article/view/216; https://doi.org/10.30758/0555-2648-2019-65-4-389-404

The purpose of the paper is to analyze the spatial-temporal variability of the time of stable ice formation in the Russian Eastern Arctic seas (the Laptev Sea, the East-Siberian Sea, the Chukchi Sea) in autumn period during 1942–2018, as well as the climatic changes for the last 20 years. The specialized information archive containing the dates of stable ice formation in the elements of regular grid (5 degrees along the parallel and 1 degree along the meridian) based on the AARI observations and satellite imagery was developed. The archive covers 2.2 million km2 of the Arctic area. During the period from 1942 to 2018 one can reveal 4 consecutive climatic periods: mean dates of ice formation (1942–1953), anomaly early dates of ice formation (1954–1988), mean dates of ice formation (1989–2002) and anomaly late dates of ice formation (2003–2018). Notice that the ice formation regime in the 21st century, by its abnormality, differs radically from that in the 20th one. For the total area of three seas, the mean date of ice formation in the 21st century became 21 days later than in the 20th one. The most significant changes (up to 45 days) take place in the Chukchi Sea. The transformation of the ice formation regime typical for the 1942–2002 to the regime of 2003–2018 happened rather quickly — approximately within 5 years. The anomaly late time of ice formation began in the Chukchi Sea in 2003, and then this anomaly propagated to the East-Siberian Sea (in 2005) and to the Laptev Sea (in 2009). The 16-year period of anomaly late ice formation consists of three 5–6-year periods depending on location of the maximum anomalies: 2003–2008 (the Chukchi Sea), 2009–2013 (the Laptev Sea), and 2014–2018 (the Chukchi Sea again). As a consequence, the period of autumn warming, which has begun in 2003, is going on till present, and the latest date of ice formation in the eastern Arctic seas for the entire 77-year period was registered just in 2018. По данным наблюдений за 1942–2018 гг. проведен анализ сроков устойчивого ледообразования в восточных морях Российской Арктики (Лаптевых, Восточно-Сибирском, Чукот­ском). Выполнено описание среднемноголетнего варианта пространственного распределения изохрон устойчивого ледообразования в осенний период. Установлено, что начиная с 2003 г. наблюдается новый многолетний период аномально позднего появления льдов осеннего об­разования. Область очень позднего ледообразования впервые появилась в Чукотском море в 2003 г. и затем постепенно смещалась с востока на запад, до акватории моря Лаптевых в 2009 г. Осеннее потепление продолжается, и осенью 2018 г. было зафиксировано абсолютно позднее ледообразование за весь 77-летний ряд наблюдений.