White Sea

The White Sea is a southern inlet of the Barents Sea situated along the northwest coast of Russia. Enclosed by the Republic of Karelia to the west, the Kola Peninsula to the north and the Kanin Peninsula to the northeast, it lies entirely within Russian internal waters. Modern administrative divisions place its coastline within Arkhangelsk Oblast, Murmansk Oblast and the Republic of Karelia. Historically significant as Russia’s early maritime gateway to Europe, the White Sea remains strategically important and is linked to the Baltic Sea by the White Sea–Baltic Canal.

Geography and Major Features

The International Hydrographic Organization delineates the northern limit of the White Sea along a line from Cape Svyatoy Nos on the Murmansk coast to Cape Kanin. Its shoreline is deeply indented, forming four major bays that together frame the transition to the Barents Sea through the narrow White Sea Throat or gorlo. Key gulfs include:

• Kandalaksha Gulf, the deepest part of the sea, reaching around 340 metres.
• Onega Bay, fed by the Onega River.
• Dvina Bay, receiving the Northern Dvina and hosting the port of Arkhangelsk.
• Mezen Bay, fed by the Mezen and Kuloy rivers.

Other important rivers entering the sea include the Vyg, Niva, Umba, Varzuga and Ponoy. The seabed varies from silt and sand in central areas to mixed stone and sand in the northern gulfs, with glacial deposits commonly exposed along the shores. The western and northern coasts are steep and rocky, while southeastern areas slope more gently.
The sea contains numerous islands, most of them small. The Solovetsky Islands, lying near Onega Bay, form the most prominent archipelago and are home to the historic Solovetsky Monastery. Kiy Island in Onega Bay and Velikiy Island in the Kandalaksha Gulf are also of note.

Hydrography and Bathymetry

The White Sea occupies a depression within the Baltic Shield, resulting in an irregular seabed with marked hollows in the northwest and around the Solovetsky region. Depths in the gorlo and the opening to the Barents Sea rarely exceed 50 metres, and an underwater ridge in the northern part further restricts deep-water exchange.
Tides are semidiurnal, with amplitudes ranging from about 1 metre in the south to as much as 10 metres in Mezen Bay. Tidal currents are strong within the bays, far exceeding the weaker currents of the open sea. Freshwater inflow averages 215 cubic kilometres per year, with major contributions from the Northern Dvina and other large rivers. Seasonal snowmelt dramatically increases freshwater input, reducing surface salinity to 23‰ in the eastern sea and as low as 10–12‰ in Dvina Bay. These variations influence nutrient content, particularly silicon and silicates, and contribute to complex circulation patterns.
The annual water exchange with the Barents Sea is substantial, with inflows and outflows each exceeding 2,000 cubic kilometres. Storms are most frequent and severe during October and November, though the shallow nature of the sea limits wave height to generally around 1 metre.

Climate and Ice Conditions

The climate ranges from polar to subarctic. Winters are long, cloudy and dominated by southwesterly winds that maintain average February temperatures around –15°C, though Arctic anticyclones can reduce temperatures to –25°C or lower. Summers are cool and humid, with average July temperatures between 8°C and 10°C. Occasional southern airflows may raise temperatures to between 17°C and 30°C.
The sea typically freezes from late autumn to late spring. Salinity differences strongly influence freezing behaviour: the lower-salinity bays freeze earlier, while the saltier waters nearer the Barents Sea freeze later. Ice thickness averages about 40 centimetres but can exceed one metre during severe winters. Since most sea ice is mobile, approximately 90% drifts northwards into the Barents Sea. Summer surface water reaches roughly 15°C in central areas but remains much cooler in the north.
Vertical temperature distributions vary dramatically. In Dvina Bay, temperatures approach 0°C at depths of around 12–15 metres, while in the Kandalaksha Gulf similar temperatures occur only at depths near 65 metres. Waters deeper than 100 metres maintain stable temperatures of 1–4°C and salinities around 30‰.

Historical Significance and Early Navigation

Knowledge of the White Sea dates back at least to the 11th century among the people of Veliky Novgorod, who recognised its value for navigation and the lucrative fur trade. One of the earliest significant settlements on its shores formed at Kholmogory in the late 14th century. In 1492 a Russian merchant fleet departed from there to Denmark, marking the establishment of Russia’s first international seaport.
Foreign interest in the region increased rapidly. In 1553 the English vessel Edward Bonaventure, commanded by Richard Chancellor, reached Kholmogory during an expedition seeking a northern route to Asia. Chancellor’s subsequent journey to Moscow initiated diplomatic and commercial relations between England and Russia. A royal charter in 1555 authorised the Muscovy Company to trade via the White Sea, stimulating significant English activity. Dutch traders soon followed, and Kholmogory developed into a thriving centre for fur and fish commerce.
As trade expanded, the shallow waters of the Northern Dvina near Kholmogory proved inadequate for growing maritime needs. In 1584 Ivan IV established a new port downstream, initially called New Kholmogory and renamed Arkhangelsk in 1596. From the 15th to the early 18th century, Arkhangelsk served as Russia’s primary window to Europe, preceding the foundation of St Petersburg.