Russian Journal of Earth Sciences Russian Journal of Earth Sciences Russian Journal of Earth Sciences 1681-1208 46577 10.2205/2021ES000767 ОРИГИНАЛЬНЫЕ СТАТЬИ ORIGINAL ARTICLES ОРИГИНАЛЬНЫЕ СТАТЬИ Measuring sea ice thickness with the LOZA georadar Measuring sea ice thickness with the LOZA georadar Morozov P A Morozov P A Berkut A I Berkut A I Vorovsky P L Vorovsky P L Morozov F P Morozov F P Pisarev S V Pisarev S V pisarev@ocean.ru Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation RAS ru Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation RAS ru LLC "Company VNIISMI" ru LLC "Company VNIISMI" ru LLC "Company VNIISMI" ru LLC "Company VNIISMI" ru LLC "Company VNIISMI" ru LLC "Company VNIISMI" ru Shirshov Institute of Oceanology RAS ru Shirshov Institute of Oceanology RAS ru 21 4 29 10 2021 https://rjes.ru/en/nauka/article/46577/view

This article documents the use of portable georadar for measuring the thickness of sea ice. This device was developed to replace the method for measuring ice thickness by drilling ice holes. The device based on the use of the LOZA georadar (ground penetrating radar, GPR) and a specially developed method of field measurements when landing on the studied ice formations. The study of the thickness and structure of sea ice by radar method is a complex problem. The salinity of sea ice determines its significant conductivity, which, in turn, causes a large attenuation of the electromagnetic signal of the georadar. The widespread GPR with a pulse power of 50-100 W are not applicable for sounding sea ice precisely because of the large signal attenuation. The LOZA instrument is equipped with a transmitter with a pulse power of 1 MW. This is, on average, 10,000 times greater than that of "traditional" GPRs. Multiple measurements of the thickness of ice formations, carried out on the one-year ice of the eastern shelf of Sakhalin Island during winter expeditions of 2016 and 2019, have shown that the device can quickly, accurately and with a high spatial resolution measure the thickness of both flat and highly deformed ice (hummocks, rafted ice, and rubble field) over large areas.

This article documents the use of portable georadar for measuring the thickness of sea ice. This device was developed to replace the method for measuring ice thickness by drilling ice holes. The device based on the use of the LOZA georadar (ground penetrating radar, GPR) and a specially developed method of field measurements when landing on the studied ice formations. The study of the thickness and structure of sea ice by radar method is a complex problem. The salinity of sea ice determines its significant conductivity, which, in turn, causes a large attenuation of the electromagnetic signal of the georadar. The widespread GPR with a pulse power of 50-100 W are not applicable for sounding sea ice precisely because of the large signal attenuation. The LOZA instrument is equipped with a transmitter with a pulse power of 1 MW. This is, on average, 10,000 times greater than that of "traditional" GPRs. Multiple measurements of the thickness of ice formations, carried out on the one-year ice of the eastern shelf of Sakhalin Island during winter expeditions of 2016 and 2019, have shown that the device can quickly, accurately and with a high spatial resolution measure the thickness of both flat and highly deformed ice (hummocks, rafted ice, and rubble field) over large areas.

 Sea ice thickness ice formations georadar GPR Sea ice thickness ice formations georadar GPR This research was supported by the State Task of the Shirshov Institute of Oceanology (0128-2021-0002).

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