Using satellite images from the KeyHole 1977 and Sentinel-2B 2020 satellites, the dynamics of the tidal delta of the Northern Dvina River was investigated. When choosing images, it is necessary to take into account seasonal and tidal fluctuations in the water level; images for the dry season with a close tide phase at the moments of shooting in different years were selected. The first compiled map of delta dynamics for the period 1977–2020 shows that the growth of delta, noted by researchers earlier, continues – the attachment of islands along the sea edge to it, the accumulation of sediments and an increase in the area of channel islands in the main river-branches, narrowing and disappearance of small streams on the delta islands. But to the long-term tendency of delta growth, the processes of erosion of the coast on the islands of the sea edge are added from the side of the Dvina Bay.

Valentina Iv. Kravtsova
Doctor of geographical sciences, leading researcher of Faculty of Geography Lomonosov Moscow State University;
1, Leninskie Gory, Moscow, 119991, Russia
e-mail: valentinamsu@yandex.ru
SPIN code: 7097-6541

Olga V. Vachnina
Research scientist of Faculty of Geography Lomonosov Moscow State University;
1, Leninskie Gory, Moscow, 119991, Russia
e-mail: vachnina-ov@yandex.ru
SPIN code: 2303-0446

Serafimа V. Lebedeva
Ph.D. Geography, hydrologist of the River and Marine Forecasts Department, Northern Agency for Hydrometeorology and Environmental Monitoring;
2, Mayakovskogo str., Arkhangelsk, 163020, Russia
researcher of the Department of Information Support of Marine and Water Management, Zubov State Oceanographic Institute;
6, Kropotkinskiy pereulok, Moscow, 119034, Russia
e-mail: hydrosima@gmail.com
SPIN code: 8356-4159

Evgeniy G. Charkovets
Senior research scientist of Faculty of Geography Lomonosov Moscow State University;
1, Leninskie Gory, Moscow, 119991, Russia
e-mail: e_x@geogr.msu.ru
SPIN code: 4888-8144

Ekaterina R. Chalova 
Ph.D.Geography, leading researcher of Faculty of Geography Lomonosov Moscow State University;
1, Leninskie Gory, Moscow, 119991, Russia
e-mail: ekar28@yandex.ru
SPIN code: 8965-4284

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