PHYSICAL OCEANOGRAPHY PHYSICAL OCEANOGRAPHY Морской гидрофизический журнал 0233-7584 1573-160X 106371 ORSZRM СПУТНИКОВАЯ ГИДРОФИЗИКА SATELLITE HYDROPHYSICS СПУТНИКОВАЯ ГИДРОФИЗИКА Enhancing the Spatial Resolution of the AMSR2 C-Band Radiometer Channels for Monitoring the Arctic Seas Using the 36.5 Ghz Measurement Channels Повышение пространственного разрешения каналов С-диапазона радиометра AMSR2 для мониторинга арктических морей с использованием каналов измере-ний на 36,5 ГГц https://orcid.org/0000-0003-4500-776X Заболотских Елизавета Валериановна Zabolotskih Elizaveta Valerianovna liza@rshu.ru https://orcid.org/0000-0001-6088-8775 Шапрон Бертран Shapron Bertran bertrand.chapron@ifremer.fr Российский государственный гидрометеорологический университет Россия Russian State Hydrometeorological University Russian Federation Французский научно-исследовательский институт исследований моря Россия Institut Français de Recherche Pour l’exploitation de la mer, Ifremer, Plouzané Russian Federation 11 07 2025 11 07 2025 41 5 694 714 05 03 2025 20 04 2025 https://ras.editorum.ru/en/nauka/article/106371/view

Цель. Исследована возможность улучшения пространственного разрешения радиометра Advanced Microwave Scanning Radiometer 2 (AMSR2) на каналах С-диапазона с помощью измере-ний на частоте 36,5 ГГц для изучения параметров подстилающей поверхности морей Арктики. Методы и результаты. Использовались результаты численного моделирования радиояркост-ной температуры (Тя) микроволнового излучения системы морской лед – океан – атмосфера в условиях нерассеивающей атмосферы Арктики и расчеты Тя для параметров атмосферы и океана по данным реанализа ERA5. В качестве эффективных коэффициентов излучения морско-го льда подставлялись рассчитанные ранее значения для всего региона Арктики. Оценивалась чувствительность Тя к атмосферному излучению, температуре поверхности и коэффициенту излучения подстилающей поверхности на каналах измерений на частоте 6,9 и 36,5 ГГц на гори-зонтальной и вертикальной поляризации, а также изменчивость указанных параметров в Аркти-ке. В зависимости от типа поверхности на основании результатов моделирования предложены формулы расчета полей Тя на частоте 6,9 ГГц повышенного пространственного разрешения, использующие Тя на частоте 6,9 ГГц исходного разрешения и Тя на частоте 36,5 ГГц спутнико-вого продукта уровня Level 1R. Выводы. Разработанный подход расширяет возможности использования данных AMSR2 для детального изучения параметров морей Арктики, частично или полностью покрытых однолет-ними льдами разного типа и сплоченности. Над областями сплошного многолетнего льда улуч-шение пространственного разрешения измерений на 6,9 ГГц, особенно на вертикальной поляри-зации, с помощью описанного подхода не представляется возможным. Ошибки и возможность применения данного подхода определяются изменчивостью параметров влагосодержания атмо-сферы в элементе низкого пространственного разрешения измерений на частоте 6,9 ГГц.

Purpose. The purpose of the work is to study the possibility of improving spatial resolution of the Ad-vanced Microwave Scanning Radiometer 2 (AMSR2) on the C-band channels using the measurements at the 36.5 GHz frequency for investigating the underlying surface parameters of the Arctic seas. Methods and Results. The results of numerical modeling of the brightness temperature (T) of the sea ice-ocean-atmosphere system microwave radiation under conditions of the non-scattering Arctic atmos-phere, as well as the calculations of T for the atmospheric and oceanic parameters based on the ERA5 reanalysis data were used. The values of sea ice effective emission coefficients previously calculated for the entire Arctic region were applied in calculations. The T sensitivity to atmospheric radiation, surface temperature and underlying surface emission coefficients at the 6.9 and 36.5 GHz measurement chan-nels at the horizontal and vertical polarizations, and also variability of the above parameters in the Arctic were assessed. Depending on the surface type and based on the modeling results, proposed are the for-mulas for calculating the T fields at the 6.9 GHz frequency at the enhanced spatial resolution, in which T at the 6.9 GHz frequency of the original resolution and T at the 36.5 GHz frequency of the Level 1R satellite product were used. Conclusions. The developed approach expands the possibilities of using the AMSR2 data for a detailed study of the parameters of Arctic seas partially or completely covered with first-year ice of various types and concentration. For the areas of continuous multi-year consolidate ice, application of the described method to improving the spatial resolution of measurements at 6.9 GHz, especially in vertical polariza-tion, seems impossible. The errors and applicability of the above approach are conditioned by the varia-bility of atmospheric water content parameters in a low spatial resolution pixel of measurements at the 6.9 GHz frequency.

 AMSR2 радиояркостная температура пространственное разрешение Арктика система морской лед – океан – атмосфера физическое моделирование морской лед AMSR2 brightness temperature spatial resolution Arctic sea ice-ocean-atmosphere system physical modeling sea ice работа выполнена в рамках государственного задания Министерства науки и высшего образова-ния РФ № FSZU-2025-0005 «Система „морской лед – океан – атмосфера“ Арктики: развитие спутниковых методов и моделей». The study was carried out within the framework of state assignment of the Ministry of Science and Higher Education of RF No. FSZU-2025-0005 “The Arctic sea ice-ocean-atmosphere system: Devel-opment of satellite methods and models”.

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