The Bothnian Bay or Bay of Bothnia (Swedish: Bottenviken; Finnish: Perämeri) is the northernmost part of the Gulf of Bothnia, which is in turn the northern part of the Baltic Sea. The land holding the bay is still rising after the weight of ice-age glaciers has been removed, and within 2,000 years the bay will be a large freshwater lake since its link to the south Kvarken is mostly less than 20 metres (66 ft) deep. The bay today is fed by several large rivers, and is relatively unaffected by tides, so has low salinity. It freezes over each year for up to six months. Compared to other parts of the Baltic, it has little plant or animal life.
| Bothnian Bay | |
|---|---|
| Bay of Bothnia | |
 The rocky shoreline of Ohtakari, in the southeast of the bay | |
  Bothnian Bay Location of the Bothnian Bay in Europe | |
| Location | Fennoscandia |
| Coordinates | 65°N 023°E / 65°N 23°E |
| Type | Sea |
| Primary outflows | Bothnian Sea |
| Catchment area | 260,675 km2 (100,647 sq mi) |
| Basin countries | Finland, Norway, and Sweden |
| Surface area | 36,800 km2 (14,200 sq mi) |
| Average depth | 43 m (141 ft) |
| Max. depth | 147 m (482 ft) |
| Water volume | 1,490 km3 (360 cu mi) |
| Frozen | 110–190 days annually |
Extent
The bay is divided from the Bothnian Sea, the southern part of the Gulf of Bothnia, by the Northern Quark (Kvarken) strait. The Northern Quark has a greatest depth of 65 metres (213 ft), with two ridges that are just 25 metres (82 ft) deep. It lies between a group of islands off Vaasa in Finland and another group at Holmöarna in Sweden. The bay is bounded by Finland to the east and Sweden to the west. The bay is asymmetric, with a smoother and shallower bottom slope on the Finnish side, and a deeper bottom with a steeper and more rugged coast on the Swedish side.
The Bothnian Bay has a catchment area of 260,675 square kilometres (100,647 sq mi). Of this, 56% lies in Finland, 44% in Sweden and less than 1% in Norway. The catchment contains about 11,500,000 hectares (28,000,000 acres) of forest, split roughly equally between Sweden and Finland.
The average depth is 41 metres (135 ft). The Luleå Deep is the deepest part of the bay, at 146 metres (479 ft), southeast of the town of Luleå. On the Finnish side the average depth is 30 metres (98 ft). The deepest part is near the island of Lönkytin, with a depth of 50 metres (160 ft).
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Map of the Gulf of Bothnia showing location of Bothnian Bay (shaded and labelled Bottenviken) -
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Finnish map of the bay – click to enlarge -
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Satellite image of Fennoscandia with sea ice covering the Bothnian Bay (white region in center)
Isostatic rebound
The bay lies in the area in Northern Europe where the ice was at its thickest during the last ice age. The Bay of Bothnia was under ice until the "Ancylus Lake" period (7500–6000 BC), when the ice sheet withdrew to the mountains of Northern Scandinavia. The land is now rising by post-glacial rebound at the highest rate in the Baltic Sea, at an estimated rate of 9 millimetres (0.35 in) a year. Today the Bothnian Bay lies around 300 metres (980 ft) higher than it did at the end of the Last Ice Age. The local population has seen the sea retreating during their lifetimes from piers and boathouses, leaving them stranded on land. Some former islands such as Porsön and Hertsön near the city of Luleå are still called islands, but are now connected to the mainland.
The maximum depth at the Kvarken sound today is around 20 metres (66 ft). Within 2,000 years, the exit from the bay at Kvarken will be raised above sea level, which will result in it becoming Europe's largest lake.
Hydrology
The Bothnian Bay has a harsher environment than other parts of the greater Baltic Sea. The bay is ice-covered for 110 to 190 days each year. Tides have little effect, but high winds driving the water from the south or north may cause the water level to rise or fall by 1.5 metres (4 ft 11 in).
Major rivers that flow into the bay include:
| River | Country | Discharge |
|---|---|---|
| Kemijoki | Finland | 556 m3/s (19,600 cu ft/s) |
| Lule River | Sweden | 506 m3/s (17,900 cu ft/s) |
| Torne River | Sweden and Finland | 388 m3/s (13,700 cu ft/s) |
| Kalix River | Sweden | 295 m3/s (10,400 cu ft/s) |
| Oulujoki | Finland | 250 m3/s (8,800 cu ft/s) |
| Pite River | Sweden | 167 m3/s (5,900 cu ft/s) |
| Skellefte River | Sweden | 162 m3/s (5,700 cu ft/s) |
| Iijoki | Finland | 164 m3/s (5,800 cu ft/s) |
The salinity is only about 0.2 psu in the northern part of the bay, dropping almost to zero in some of the archipelagos with large river inflows. The low salinity and cold temperatures in winter results in ice that is considerably stronger than more saline or warmer ice.
Islands
If an island is defined as an area of land more than 20 square metres (220 sq ft) that is surrounded by water, the Bay of Bothnia has 4,001 islands. The largest island is Hailuoto. The north of the bay contains a large archipelago area. The Swedish portion of this area is the Norrbotten archipelago. This is divided into the Piteå, Luleå, Kalix and Haparanda archipelagos. Many of the islands are uninhabited and in a natural state. In the winter the larger islands may be accessed via ice roads. Some of them are inhabited or have seasonal fishing villages used by people from the mainland.
The Swedish Haparanda Archipelago National Park (Swedish: Haparanda skärgårds nationalpark) occupies the Haparanda group of islands, bordering the Finnish Bothnian Bay National Park. It includes the larger islands of Sandskär and Seskar Furö, and some smaller islands and skerries. All of these islands have emerged in the last 1,500 years as the bed of the bay has risen. The Bay of Bothnia National Park in the Finnish section (Finnish: Perämeren kansallispuisto, Swedish: Bottenvikens nationalpark), established in 1991, is located in the archipelago offshore from Tornio and Kemi. It covers 157 square kilometres (61 sq mi) of which about 2.5 square kilometres (0.97 sq mi) is land.
Climate
The immediate coastal areas of the Bothnian Bay tend to be bordering between humid continental and subarctic climates. The summers on the coastlines are the northernmost coastlines to average above 20 °C (68 °F) in summer. In winter the sea freezes over, many times completely. This means that there is vast seasonal lag offshore such as on the island of Rödkallen on the Swedish side. Due to the mild nature of summers and the low diurnals, offshore islands tend to be humid continental since September usually stays above 10 °C (50 °F) means.
| Climate data for Luleå Airport, 2002–2020 averages; extremes since 1944 | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Record high °C (°F) | 10.3 (50.5) | 9.8 (49.6) | 13.4 (56.1) | 18.1 (64.6) | 28.4 (83.1) | 32.2 (90.0) | 32.1 (89.8) | 29.2 (84.6) | 22.5 (72.5) | 16.9 (62.4) | 13.0 (55.4) | 8.5 (47.3) | 32.2 (90.0) |
| Mean maximum °C (°F) | 4.0 (39.2) | 5.3 (41.5) | 8.7 (47.7) | 13.3 (55.9) | 21.4 (70.5) | 24.3 (75.7) | 26.7 (80.1) | 24.1 (75.4) | 18.8 (65.8) | 12.5 (54.5) | 7.2 (45.0) | 5.3 (41.5) | 27.8 (82.0) |
| Mean daily maximum °C (°F) | −5.2 (22.6) | −4.5 (23.9) | 0.2 (32.4) | 5.6 (42.1) | 12.3 (54.1) | 17.4 (63.3) | 20.5 (68.9) | 18.7 (65.7) | 13.4 (56.1) | 5.9 (42.6) | 0.6 (33.1) | −2.0 (28.4) | 6.9 (44.4) |
| Daily mean °C (°F) | −9.1 (15.6) | −8.7 (16.3) | −4.2 (24.4) | 1.5 (34.7) | 7.7 (45.9) | 13.3 (55.9) | 16.6 (61.9) | 15.0 (59.0) | 9.9 (49.8) | 2.9 (37.2) | −2.4 (27.7) | −5.6 (21.9) | 3.1 (37.5) |
| Mean daily minimum °C (°F) | −13.0 (8.6) | −12.9 (8.8) | −8.5 (16.7) | −2.6 (27.3) | 3.1 (37.6) | 9.1 (48.4) | 12.6 (54.7) | 11.2 (52.2) | 6.3 (43.3) | −0.2 (31.6) | −5.4 (22.3) | −9.1 (15.6) | −0.8 (30.6) |
| Mean minimum °C (°F) | −26.6 (−15.9) | −25.7 (−14.3) | −20.1 (−4.2) | −10.2 (13.6) | −3.1 (26.4) | 3.5 (38.3) | 7.3 (45.1) | 4.3 (39.7) | −0.9 (30.4) | −9.7 (14.5) | −15.8 (3.6) | −21.2 (−6.2) | −29.2 (−20.6) |
| Record low °C (°F) | −42.3 (−44.1) | −38.2 (−36.8) | −32.3 (−26.1) | −20.4 (−4.7) | −8.8 (16.2) | −1.2 (29.8) | 3.2 (37.8) | −0.2 (31.6) | −8.4 (16.9) | −20.7 (−5.3) | −30.3 (−22.5) | −33.7 (−28.7) | −42.3 (−44.1) |
| Average precipitation mm (inches) | 57.9 (2.28) | 36.8 (1.45) | 30.2 (1.19) | 31.3 (1.23) | 45.1 (1.78) | 65.8 (2.59) | 67.6 (2.66) | 69.5 (2.74) | 66.0 (2.60) | 52.9 (2.08) | 52.6 (2.07) | 56.3 (2.22) | 632 (24.89) |
| Average extreme snow depth cm (inches) | 55 (22) | 72 (28) | 75 (30) | 64 (25) | — | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 5 (2.0) | 16 (6.3) | 30 (12) | 79 (31) |
| Mean monthly sunshine hours | 21 | 78 | 172 | 225 | 289 | 305 | 310 | 245 | 154 | 92 | 38 | 3 | 1,932 |
| Source 1: SMHI | |||||||||||||
| Source 2: SMHI | |||||||||||||
| Climate data for Rödkallen, (2002–2020 averages; extremes from available data since 1961; sunshine from Luleå 2002–2020) | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Record high °C (°F) | 7.1 (44.8) | 7.0 (44.6) | 6.9 (44.4) | 10.2 (50.4) | 21.9 (71.4) | 26.2 (79.2) | 28.9 (84.0) | 25.0 (77.0) | 19.2 (66.6) | 13.3 (55.9) | 10.0 (50.0) | 5.6 (42.1) | 28.9 (84.0) |
| Mean maximum °C (°F) | 2.5 (36.5) | 2.6 (36.7) | 4.2 (39.6) | 7.3 (45.1) | 15.7 (60.3) | 20.1 (68.2) | 22.4 (72.3) | 21.1 (70.0) | 16.5 (61.7) | 11.1 (52.0) | 6.4 (43.5) | 3.8 (38.8) | 23.4 (74.1) |
| Mean daily maximum °C (°F) | −3.4 (25.9) | −4.1 (24.6) | −1.4 (29.5) | 2.6 (36.7) | 8.3 (46.9) | 14.2 (57.6) | 18.1 (64.6) | 17.2 (63.0) | 12.8 (55.0) | 6.7 (44.1) | 2.5 (36.5) | −0.6 (30.9) | 6.1 (42.9) |
| Daily mean °C (°F) | −6.1 (21.0) | −7.4 (18.7) | −4.7 (23.5) | 0.2 (32.4) | 5.9 (42.6) | 12.0 (53.6) | 16.2 (61.2) | 15.5 (59.9) | 11.1 (52.0) | 5.1 (41.2) | 0.8 (33.4) | −2.7 (27.1) | 3.8 (38.9) |
| Mean daily minimum °C (°F) | −8.7 (16.3) | −10.6 (12.9) | −8.0 (17.6) | −2.3 (27.9) | 3.4 (38.1) | 9.8 (49.6) | 14.2 (57.6) | 13.7 (56.7) | 9.4 (48.9) | 3.5 (38.3) | −1.0 (30.2) | −4.8 (23.4) | 1.5 (34.8) |
| Mean minimum °C (°F) | −20.9 (−5.6) | −22.3 (−8.1) | −17.7 (0.1) | −8.6 (16.5) | −1.3 (29.7) | 5.6 (42.1) | 10.4 (50.7) | 9.2 (48.6) | 4.1 (39.4) | −2.6 (27.3) | −7.4 (18.7) | −13.8 (7.2) | −25.3 (−13.5) |
| Record low °C (°F) | −38.0 (−36.4) | −33.1 (−27.6) | −27.0 (−16.6) | −19.7 (−3.5) | −9.0 (15.8) | 1.7 (35.1) | 6.5 (43.7) | 5.6 (42.1) | −0.4 (31.3) | −10.3 (13.5) | −20.5 (−4.9) | −27.7 (−17.9) | −38.0 (−36.4) |
| Average precipitation mm (inches) | 25.5 (1.00) | 19.3 (0.76) | 18.6 (0.73) | 21.7 (0.85) | 32.8 (1.29) | 47.0 (1.85) | 49.2 (1.94) | 46.8 (1.84) | 47.6 (1.87) | 50.0 (1.97) | 44.8 (1.76) | 40.0 (1.57) | 443.3 (17.43) |
| Mean monthly sunshine hours | 21 | 78 | 172 | 225 | 289 | 305 | 310 | 245 | 154 | 92 | 38 | 3 | 1,932 |
| Source 1: SMHI Open Data | |||||||||||||
| Source 2: SMHI Open Data | |||||||||||||
| Climate data for Haparanda (2002–2020; extremes since 1901) | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Record high °C (°F) | 8.4 (47.1) | 7.8 (46.0) | 10.3 (50.5) | 18.5 (65.3) | 28.8 (83.8) | 31.4 (88.5) | 33.6 (92.5) | 29.7 (85.5) | 24.0 (75.2) | 17.0 (62.6) | 11.5 (52.7) | 7.0 (44.6) | 33.6 (92.5) |
| Mean maximum °C (°F) | 2.5 (36.5) | 3.4 (38.1) | 7.5 (45.5) | 12.7 (54.9) | 22.3 (72.1) | 25.2 (77.4) | 27.1 (80.8) | 24.6 (76.3) | 18.7 (65.7) | 11.8 (53.2) | 6.4 (43.5) | 3.7 (38.7) | 28.1 (82.6) |
| Mean daily maximum °C (°F) | −5.9 (21.4) | −5.1 (22.8) | −0.3 (31.5) | 5.4 (41.7) | 12.3 (54.1) | 17.8 (64.0) | 21.1 (70.0) | 18.7 (65.7) | 13.3 (55.9) | 5.6 (42.1) | 0.4 (32.7) | −2.4 (27.7) | 6.7 (44.1) |
| Daily mean °C (°F) | −9.8 (14.4) | −9.1 (15.6) | −4.9 (23.2) | 1.1 (34.0) | 7.4 (45.3) | 12.9 (55.2) | 16.5 (61.7) | 14.4 (57.9) | 9.4 (48.9) | 2.4 (36.3) | −2.4 (27.7) | −5.8 (21.6) | 2.7 (36.8) |
| Mean daily minimum °C (°F) | −13.6 (7.5) | −13.1 (8.4) | −9.5 (14.9) | −3.3 (26.1) | 2.5 (36.5) | 8.0 (46.4) | 11.8 (53.2) | 10.1 (50.2) | 5.5 (41.9) | −0.8 (30.6) | −5.1 (22.8) | −9.1 (15.6) | −1.4 (29.5) |
| Mean minimum °C (°F) | −27.6 (−17.7) | −27.3 (−17.1) | −22.3 (−8.1) | −12.1 (10.2) | −4.3 (24.3) | 1.8 (35.2) | 5.3 (41.5) | 2.0 (35.6) | −2.5 (27.5) | −10.1 (13.8) | −16.0 (3.2) | −21.5 (−6.7) | −29.7 (−21.5) |
| Record low °C (°F) | −40.8 (−41.4) | −41.7 (−43.1) | −37.5 (−35.5) | −26.0 (−14.8) | −10.5 (13.1) | −1.5 (29.3) | 2.2 (36.0) | −1.8 (28.8) | −8.1 (17.4) | −23.0 (−9.4) | −32.3 (−26.1) | −37.3 (−35.1) | −41.7 (−43.1) |
| Average precipitation mm (inches) | 56.5 (2.22) | 44.9 (1.77) | 35.8 (1.41) | 32.4 (1.28) | 45.5 (1.79) | 52.8 (2.08) | 60.7 (2.39) | 57.2 (2.25) | 64.8 (2.55) | 59.2 (2.33) | 68.9 (2.71) | 63.6 (2.50) | 642.3 (25.28) |
| Average extreme snow depth cm (inches) | 47 (19) | 67 (26) | 76 (30) | 62 (24) | 7 (2.8) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 4 (1.6) | 13 (5.1) | 26 (10) | 77 (30) |
| Source 1: SMHI Open Data | |||||||||||||
| Source 2: SMHI Monthly Data | |||||||||||||
| Climate data for Oulu, 1981-2010 normals, records 1921 - present | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Record high °C (°F) | 9.3 (48.7) | 7.8 (46.0) | 11.5 (52.7) | 23.9 (75.0) | 29.9 (85.8) | 32.3 (90.1) | 33.3 (91.9) | 30.5 (86.9) | 25.4 (77.7) | 20.5 (68.9) | 11.2 (52.2) | 8.2 (46.8) | 33.3 (91.9) |
| Mean daily maximum °C (°F) | −6 (21) | −5.7 (21.7) | −0.9 (30.4) | 5.6 (42.1) | 12.5 (54.5) | 17.9 (64.2) | 20.9 (69.6) | 18.3 (64.9) | 12.5 (54.5) | 5.8 (42.4) | −0.4 (31.3) | −4 (25) | 6.4 (43.5) |
| Daily mean °C (°F) | −9.6 (14.7) | −9.3 (15.3) | −4.8 (23.4) | 1.4 (34.5) | 7.8 (46.0) | 13.5 (56.3) | 16.5 (61.7) | 14.1 (57.4) | 8.9 (48.0) | 3.3 (37.9) | −2.8 (27.0) | −7.1 (19.2) | 2.7 (36.8) |
| Mean daily minimum °C (°F) | −13.6 (7.5) | −13.3 (8.1) | −8.8 (16.2) | −2.6 (27.3) | 3.3 (37.9) | 9.0 (48.2) | 12.2 (54.0) | 10.1 (50.2) | 5.4 (41.7) | 0.8 (33.4) | −5.5 (22.1) | −10.8 (12.6) | −1.2 (29.9) |
| Record low °C (°F) | −37.5 (−35.5) | −41.5 (−42.7) | −32 (−26) | −21.4 (−6.5) | −9.1 (15.6) | −6.1 (21.0) | 3.6 (38.5) | −1.5 (29.3) | −8 (18) | −20.6 (−5.1) | −33 (−27) | −37.2 (−35.0) | −41.5 (−42.7) |
| Average precipitation mm (inches) | 31 (1.2) | 26 (1.0) | 26 (1.0) | 20 (0.8) | 37 (1.5) | 46 (1.8) | 71 (2.8) | 65 (2.6) | 44 (1.7) | 45 (1.8) | 36 (1.4) | 30 (1.2) | 477 (18.8) |
| Average precipitation days | 10 | 8 | 8 | 6 | 7 | 7 | 9 | 10 | 9 | 10 | 11 | 10 | 105 |
| Average relative humidity (%) (daily average) | 87 | 86 | 82 | 73 | 67 | 66 | 71 | 76 | 82 | 86 | 90 | 89 | 80 |
| Mean monthly sunshine hours | 24 | 69 | 137 | 208 | 273 | 296 | 283 | 212 | 133 | 69 | 28 | 8 | 1,740 |
| Source 1: FMI | |||||||||||||
| Source 2: FMI (record highs and lows 1961–present) FMI(record highs and lows 1921–1961) | |||||||||||||
Ecology
The Quark ridge at the south of the bay defines the dividing line beyond which many salt water species are unable to survive. Instead of the red and brown algae found further south, the bay has predominantly green algae and phanerogams. Annual plant species are almost completely dominant. The only perennials are a few specimens of the freshwater cryptogam Isoetes echinospora and the moss Fontinalis dalecarlica. Often the green algae have a dense covering of epiphytic diatoms. The shores, beaches and shallows include a variety of northern plant species including the endemic yellow hair grass (Deschampsia bottnica).
The only filter feeders are Ephydatia and, at the river mouths, small numbers of freshwater mussels. Bivalves make up 9% of animal biomass. Crustaceans, mostly Saduria entomon make up 45% and gastropoda 30%. The gastropoda are grazing snails related to freshwater species.
Fish species found in the area's lakes and rivers also live in the bay, including roach, perch, pike and grayling.
Ringed seal, grey seal, cod, herring and salmon may also be found in the bay. In the 16th century seals were hunted in the Bay of Bothnia. Ringed seals were captured using nets in the inshore open water, and were stalked and captured in their dens or at breathing holes. Both grey and ringed seals were hunted along the edge of the ice. Wild vendace roe harvested from the Kalix River, known as Kalix Löjrom or as sea gold, is a delicacy with a European protected designation of origin.
Birdlife includes the black guillemot, velvet scoter, oystercatcher, lesser black-backed gull, western capercaillie and willow ptarmigan. Moose and hare are found on the islands, as on the mainland.
Occasionally, whales have been observed in the Bothnian Sea and remains of extinct Atlantic gray whale was found from Gräsö while it is not clear whether or not whales might once have reached Bothnian Bay historically.
Population
Ports on the Finnish side include Haukipudas, Jakobstad, Kemi, Kokkola, Oulu, Raahe and Tornio. The largest towns by population on the Finnish side as of 2013 were Oulu (192,680), Tornio (22,374), Kemi (22,157), Kempele (16,549), Raahe (25,641), Kalajoki (12,637), Kokkola (46,697) and Jakobstad (19,636). In Finland the catchment area included about 544,000 hectares (1,340,000 acres) of arable land as of 1993. There were four Finnish pulp and paper mills, of which two (Veitsiluoto Oy and Metsä Botnia Oy) were producing bleached kraft paper.
On the Swedish side ports include Haparanda, Karlsborg, Kalix, Luleå, Piteå and Skellefteå. The largest towns on the Swedish side as of 2013 were Luleå (74,000), Skellefteå (71,641), Piteå (40,860) and Kalix (16,926). Luleå is the largest city in Norrbotten, with the largest airport. The 1,312 islands of the Luleå archipelago are an important tourist attraction, as is the Gammelstad church village, listed as a Unesco World Heritage site. As of 1993 there were about 113,000 hectares (280,000 acres) of arable land in the Swedish part of the catchment basin, mostly used for small-scale low-intensity farming. There were five pulp and paper mills, of which one produced bleached kraft paper.
In the late 1960s the bay was being used to transport fuel oil to the Finnish settlements around the bay. In 1968 about 950,000 tons of cellulose and 230,600 tons of paper and cardboard were exported, a figure that was rising. In 1968 ships calling at the Finnish ports carried about 388,872 tons of iron bars and 64,326 tons of steel sheets. Mining and mineral products such as coal and ore were carried to and from the ports, and steel products were exported. Sea transport continued throughout the winter. In 1993 there were two non-ferrous heavy metal smelters, in Rönnskär and Kokkola, emitting significant quantities of heavy metals. Efforts were being made to reduce emissions. The drainage basin also held three iron and steel plants and a number of mines.
Human activities have affected the fragile sub-arctic environment. Dredging and other activities related to sea transport affect marine life. Agriculture, forestry and peat mining in the catchment basin add nutrients to the bay, affecting the ecological balance, while pollutants are delivered from steel mills and from pulp and paper mills around the bay, as well as from sewage treatment plants. Steel mills and stainless steel plants may have released nickel and chromium. Efforts have been made to reduce pollution through improved technology, but some areas along the Finnish coastline show evidence of eutrophication. Compared to other parts of the Baltic, higher levels of nitrate have been found in the Bothnian Bay and lower levels of phosphate and silicates.
Gallery
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![image]()
The bridge to Seskarö, Sweden -
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Finnish icebreaker MSV Fennica in the Bay -
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Looking back from the Icebreaker Sampo near Kemi, Finland -
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Outokumpu mill in Tornio -
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Old mill buildings and harbour in Toppila, Oulu, Finland -
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Buildings and the birdwatching tower at Varessäikkä harbour, Siikajoki, Finland -
![image]()
Old fisherman's cottage -
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Lönkytin island -
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The island of Kahvankari in Oulu, Finland -
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The eastern shore of the Kellon Kraaseli island, Haukipudas, Finland -
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Bothnian Bay in Kemi, Finland -
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Sunset at Hiekkasärkät, Kalajoki, Finland
References
Citations
- Leppäranta & Myrberg 2009, p. 55.
- Szefer 2002, p. 11.
- Baltic Sea Joint Comprehensive Environmental Action, pp. 2–3.
- Leppäranta & Myrberg 2009, p. 56.
- Merikartta Perämeri osa 57.
- Røed 2011.
- Leppäranta & Myrberg 2009, p. 11.
- Nesje 2006.
- About the Bay ... Bottenvikens skärgård.
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The Bothnian Bay or Bay of Bothnia Swedish Bottenviken Finnish Perameri is the northernmost part of the Gulf of Bothnia which is in turn the northern part of the Baltic Sea The land holding the bay is still rising after the weight of ice age glaciers has been removed and within 2 000 years the bay will be a large freshwater lake since its link to the south Kvarken is mostly less than 20 metres 66 ft deep The bay today is fed by several large rivers and is relatively unaffected by tides so has low salinity It freezes over each year for up to six months Compared to other parts of the Baltic it has little plant or animal life Bothnian BayBay of BothniaThe rocky shoreline of Ohtakari in the southeast of the bayBothnian BayLocation of the Bothnian Bay in EuropeLocationFennoscandiaCoordinates65 N 023 E 65 N 23 E 65 23TypeSeaPrimary outflowsBothnian SeaCatchment area260 675 km2 100 647 sq mi Basin countriesFinland Norway and SwedenSurface area36 800 km2 14 200 sq mi Average depth43 m 141 ft Max depth147 m 482 ft Water volume1 490 km3 360 cu mi Frozen110 190 days annuallyExtentThe bay is divided from the Bothnian Sea the southern part of the Gulf of Bothnia by the Northern Quark Kvarken strait The Northern Quark has a greatest depth of 65 metres 213 ft with two ridges that are just 25 metres 82 ft deep It lies between a group of islands off Vaasa in Finland and another group at Holmoarna in Sweden The bay is bounded by Finland to the east and Sweden to the west The bay is asymmetric with a smoother and shallower bottom slope on the Finnish side and a deeper bottom with a steeper and more rugged coast on the Swedish side The Bothnian Bay has a catchment area of 260 675 square kilometres 100 647 sq mi Of this 56 lies in Finland 44 in Sweden and less than 1 in Norway The catchment contains about 11 500 000 hectares 28 000 000 acres of forest split roughly equally between Sweden and Finland The average depth is 41 metres 135 ft The Lulea Deep is the deepest part of the bay at 146 metres 479 ft southeast of the town of Lulea On the Finnish side the average depth is 30 metres 98 ft The deepest part is near the island of Lonkytin with a depth of 50 metres 160 ft Map of the Gulf of Bothnia showing location of Bothnian Bay shaded and labelled Bottenviken Finnish map of the bay click to enlarge Satellite image of Fennoscandia with sea ice covering the Bothnian Bay white region in center Isostatic rebound The bay lies in the area in Northern Europe where the ice was at its thickest during the last ice age The Bay of Bothnia was under ice until the Ancylus Lake period 7500 6000 BC when the ice sheet withdrew to the mountains of Northern Scandinavia The land is now rising by post glacial rebound at the highest rate in the Baltic Sea at an estimated rate of 9 millimetres 0 35 in a year Today the Bothnian Bay lies around 300 metres 980 ft higher than it did at the end of the Last Ice Age The local population has seen the sea retreating during their lifetimes from piers and boathouses leaving them stranded on land Some former islands such as Porson and Hertson near the city of Lulea are still called islands but are now connected to the mainland The maximum depth at the Kvarken sound today is around 20 metres 66 ft Within 2 000 years the exit from the bay at Kvarken will be raised above sea level which will result in it becoming Europe s largest lake HydrologyA cargo ship approaching the Vihreasaari harbour in Oulu Finland while the Bay of Bothnia starts to freeze for the winterThe ice road between the Hailuoto island and the mainland The Bothnian Bay has a harsher environment than other parts of the greater Baltic Sea The bay is ice covered for 110 to 190 days each year Tides have little effect but high winds driving the water from the south or north may cause the water level to rise or fall by 1 5 metres 4 ft 11 in Major rivers that flow into the bay include River Country DischargeKemijoki Finland 556 m3 s 19 600 cu ft s Lule River Sweden 506 m3 s 17 900 cu ft s Torne River Sweden and Finland 388 m3 s 13 700 cu ft s Kalix River Sweden 295 m3 s 10 400 cu ft s Oulujoki Finland 250 m3 s 8 800 cu ft s Pite River Sweden 167 m3 s 5 900 cu ft s Skellefte River Sweden 162 m3 s 5 700 cu ft s Iijoki Finland 164 m3 s 5 800 cu ft s The salinity is only about 0 2 psu in the northern part of the bay dropping almost to zero in some of the archipelagos with large river inflows The low salinity and cold temperatures in winter results in ice that is considerably stronger than more saline or warmer ice IslandsThe Hermanni islands A wintery view of a group of small islands in the Bothnian Bay near Oulu FinlandThe lighthouse on the island of Pite Ronnskar in Bothnian Bay If an island is defined as an area of land more than 20 square metres 220 sq ft that is surrounded by water the Bay of Bothnia has 4 001 islands The largest island is Hailuoto The north of the bay contains a large archipelago area The Swedish portion of this area is the Norrbotten archipelago This is divided into the Pitea Lulea Kalix and Haparanda archipelagos Many of the islands are uninhabited and in a natural state In the winter the larger islands may be accessed via ice roads Some of them are inhabited or have seasonal fishing villages used by people from the mainland The Swedish Haparanda Archipelago National Park Swedish Haparanda skargards nationalpark occupies the Haparanda group of islands bordering the Finnish Bothnian Bay National Park It includes the larger islands of Sandskar and Seskar Furo and some smaller islands and skerries All of these islands have emerged in the last 1 500 years as the bed of the bay has risen The Bay of Bothnia National Park in the Finnish section Finnish Perameren kansallispuisto Swedish Bottenvikens nationalpark established in 1991 is located in the archipelago offshore from Tornio and Kemi It covers 157 square kilometres 61 sq mi of which about 2 5 square kilometres 0 97 sq mi is land ClimateThe immediate coastal areas of the Bothnian Bay tend to be bordering between humid continental and subarctic climates The summers on the coastlines are the northernmost coastlines to average above 20 C 68 F in summer In winter the sea freezes over many times completely This means that there is vast seasonal lag offshore such as on the island of Rodkallen on the Swedish side Due to the mild nature of summers and the low diurnals offshore islands tend to be humid continental since September usually stays above 10 C 50 F means Climate data for Lulea Airport 2002 2020 averages extremes since 1944Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec YearRecord high C F 10 3 50 5 9 8 49 6 13 4 56 1 18 1 64 6 28 4 83 1 32 2 90 0 32 1 89 8 29 2 84 6 22 5 72 5 16 9 62 4 13 0 55 4 8 5 47 3 32 2 90 0 Mean maximum C F 4 0 39 2 5 3 41 5 8 7 47 7 13 3 55 9 21 4 70 5 24 3 75 7 26 7 80 1 24 1 75 4 18 8 65 8 12 5 54 5 7 2 45 0 5 3 41 5 27 8 82 0 Mean daily maximum C F 5 2 22 6 4 5 23 9 0 2 32 4 5 6 42 1 12 3 54 1 17 4 63 3 20 5 68 9 18 7 65 7 13 4 56 1 5 9 42 6 0 6 33 1 2 0 28 4 6 9 44 4 Daily mean C F 9 1 15 6 8 7 16 3 4 2 24 4 1 5 34 7 7 7 45 9 13 3 55 9 16 6 61 9 15 0 59 0 9 9 49 8 2 9 37 2 2 4 27 7 5 6 21 9 3 1 37 5 Mean daily minimum C F 13 0 8 6 12 9 8 8 8 5 16 7 2 6 27 3 3 1 37 6 9 1 48 4 12 6 54 7 11 2 52 2 6 3 43 3 0 2 31 6 5 4 22 3 9 1 15 6 0 8 30 6 Mean minimum C F 26 6 15 9 25 7 14 3 20 1 4 2 10 2 13 6 3 1 26 4 3 5 38 3 7 3 45 1 4 3 39 7 0 9 30 4 9 7 14 5 15 8 3 6 21 2 6 2 29 2 20 6 Record low C F 42 3 44 1 38 2 36 8 32 3 26 1 20 4 4 7 8 8 16 2 1 2 29 8 3 2 37 8 0 2 31 6 8 4 16 9 20 7 5 3 30 3 22 5 33 7 28 7 42 3 44 1 Average precipitation mm inches 57 9 2 28 36 8 1 45 30 2 1 19 31 3 1 23 45 1 1 78 65 8 2 59 67 6 2 66 69 5 2 74 66 0 2 60 52 9 2 08 52 6 2 07 56 3 2 22 632 24 89 Average extreme snow depth cm inches 55 22 72 28 75 30 64 25 0 0 0 0 0 0 0 0 5 2 0 16 6 3 30 12 79 31 Mean monthly sunshine hours 21 78 172 225 289 305 310 245 154 92 38 3 1 932Source 1 SMHISource 2 SMHI Climate data for Rodkallen 2002 2020 averages extremes from available data since 1961 sunshine from Lulea 2002 2020 Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec YearRecord high C F 7 1 44 8 7 0 44 6 6 9 44 4 10 2 50 4 21 9 71 4 26 2 79 2 28 9 84 0 25 0 77 0 19 2 66 6 13 3 55 9 10 0 50 0 5 6 42 1 28 9 84 0 Mean maximum C F 2 5 36 5 2 6 36 7 4 2 39 6 7 3 45 1 15 7 60 3 20 1 68 2 22 4 72 3 21 1 70 0 16 5 61 7 11 1 52 0 6 4 43 5 3 8 38 8 23 4 74 1 Mean daily maximum C F 3 4 25 9 4 1 24 6 1 4 29 5 2 6 36 7 8 3 46 9 14 2 57 6 18 1 64 6 17 2 63 0 12 8 55 0 6 7 44 1 2 5 36 5 0 6 30 9 6 1 42 9 Daily mean C F 6 1 21 0 7 4 18 7 4 7 23 5 0 2 32 4 5 9 42 6 12 0 53 6 16 2 61 2 15 5 59 9 11 1 52 0 5 1 41 2 0 8 33 4 2 7 27 1 3 8 38 9 Mean daily minimum C F 8 7 16 3 10 6 12 9 8 0 17 6 2 3 27 9 3 4 38 1 9 8 49 6 14 2 57 6 13 7 56 7 9 4 48 9 3 5 38 3 1 0 30 2 4 8 23 4 1 5 34 8 Mean minimum C F 20 9 5 6 22 3 8 1 17 7 0 1 8 6 16 5 1 3 29 7 5 6 42 1 10 4 50 7 9 2 48 6 4 1 39 4 2 6 27 3 7 4 18 7 13 8 7 2 25 3 13 5 Record low C F 38 0 36 4 33 1 27 6 27 0 16 6 19 7 3 5 9 0 15 8 1 7 35 1 6 5 43 7 5 6 42 1 0 4 31 3 10 3 13 5 20 5 4 9 27 7 17 9 38 0 36 4 Average precipitation mm inches 25 5 1 00 19 3 0 76 18 6 0 73 21 7 0 85 32 8 1 29 47 0 1 85 49 2 1 94 46 8 1 84 47 6 1 87 50 0 1 97 44 8 1 76 40 0 1 57 443 3 17 43 Mean monthly sunshine hours 21 78 172 225 289 305 310 245 154 92 38 3 1 932Source 1 SMHI Open DataSource 2 SMHI Open Data Climate data for Haparanda 2002 2020 extremes since 1901 Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec YearRecord high C F 8 4 47 1 7 8 46 0 10 3 50 5 18 5 65 3 28 8 83 8 31 4 88 5 33 6 92 5 29 7 85 5 24 0 75 2 17 0 62 6 11 5 52 7 7 0 44 6 33 6 92 5 Mean maximum C F 2 5 36 5 3 4 38 1 7 5 45 5 12 7 54 9 22 3 72 1 25 2 77 4 27 1 80 8 24 6 76 3 18 7 65 7 11 8 53 2 6 4 43 5 3 7 38 7 28 1 82 6 Mean daily maximum C F 5 9 21 4 5 1 22 8 0 3 31 5 5 4 41 7 12 3 54 1 17 8 64 0 21 1 70 0 18 7 65 7 13 3 55 9 5 6 42 1 0 4 32 7 2 4 27 7 6 7 44 1 Daily mean C F 9 8 14 4 9 1 15 6 4 9 23 2 1 1 34 0 7 4 45 3 12 9 55 2 16 5 61 7 14 4 57 9 9 4 48 9 2 4 36 3 2 4 27 7 5 8 21 6 2 7 36 8 Mean daily minimum C F 13 6 7 5 13 1 8 4 9 5 14 9 3 3 26 1 2 5 36 5 8 0 46 4 11 8 53 2 10 1 50 2 5 5 41 9 0 8 30 6 5 1 22 8 9 1 15 6 1 4 29 5 Mean minimum C F 27 6 17 7 27 3 17 1 22 3 8 1 12 1 10 2 4 3 24 3 1 8 35 2 5 3 41 5 2 0 35 6 2 5 27 5 10 1 13 8 16 0 3 2 21 5 6 7 29 7 21 5 Record low C F 40 8 41 4 41 7 43 1 37 5 35 5 26 0 14 8 10 5 13 1 1 5 29 3 2 2 36 0 1 8 28 8 8 1 17 4 23 0 9 4 32 3 26 1 37 3 35 1 41 7 43 1 Average precipitation mm inches 56 5 2 22 44 9 1 77 35 8 1 41 32 4 1 28 45 5 1 79 52 8 2 08 60 7 2 39 57 2 2 25 64 8 2 55 59 2 2 33 68 9 2 71 63 6 2 50 642 3 25 28 Average extreme snow depth cm inches 47 19 67 26 76 30 62 24 7 2 8 0 0 0 0 0 0 0 0 4 1 6 13 5 1 26 10 77 30 Source 1 SMHI Open DataSource 2 SMHI Monthly Data Climate data for Oulu 1981 2010 normals records 1921 presentMonth Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec YearRecord high C F 9 3 48 7 7 8 46 0 11 5 52 7 23 9 75 0 29 9 85 8 32 3 90 1 33 3 91 9 30 5 86 9 25 4 77 7 20 5 68 9 11 2 52 2 8 2 46 8 33 3 91 9 Mean daily maximum C F 6 21 5 7 21 7 0 9 30 4 5 6 42 1 12 5 54 5 17 9 64 2 20 9 69 6 18 3 64 9 12 5 54 5 5 8 42 4 0 4 31 3 4 25 6 4 43 5 Daily mean C F 9 6 14 7 9 3 15 3 4 8 23 4 1 4 34 5 7 8 46 0 13 5 56 3 16 5 61 7 14 1 57 4 8 9 48 0 3 3 37 9 2 8 27 0 7 1 19 2 2 7 36 8 Mean daily minimum C F 13 6 7 5 13 3 8 1 8 8 16 2 2 6 27 3 3 3 37 9 9 0 48 2 12 2 54 0 10 1 50 2 5 4 41 7 0 8 33 4 5 5 22 1 10 8 12 6 1 2 29 9 Record low C F 37 5 35 5 41 5 42 7 32 26 21 4 6 5 9 1 15 6 6 1 21 0 3 6 38 5 1 5 29 3 8 18 20 6 5 1 33 27 37 2 35 0 41 5 42 7 Average precipitation mm inches 31 1 2 26 1 0 26 1 0 20 0 8 37 1 5 46 1 8 71 2 8 65 2 6 44 1 7 45 1 8 36 1 4 30 1 2 477 18 8 Average precipitation days 10 8 8 6 7 7 9 10 9 10 11 10 105Average relative humidity daily average 87 86 82 73 67 66 71 76 82 86 90 89 80Mean monthly sunshine hours 24 69 137 208 273 296 283 212 133 69 28 8 1 740Source 1 FMISource 2 FMI record highs and lows 1961 present FMI record highs and lows 1921 1961 EcologyA fishing village of the Kallankari Islands part of Kalajoki The Quark ridge at the south of the bay defines the dividing line beyond which many salt water species are unable to survive Instead of the red and brown algae found further south the bay has predominantly green algae and phanerogams Annual plant species are almost completely dominant The only perennials are a few specimens of the freshwater cryptogam Isoetes echinospora and the moss Fontinalis dalecarlica Often the green algae have a dense covering of epiphytic diatoms The shores beaches and shallows include a variety of northern plant species including the endemic yellow hair grass Deschampsia bottnica The only filter feeders are Ephydatia and at the river mouths small numbers of freshwater mussels Bivalves make up 9 of animal biomass Crustaceans mostly Saduria entomon make up 45 and gastropoda 30 The gastropoda are grazing snails related to freshwater species Fish species found in the area s lakes and rivers also live in the bay including roach perch pike and grayling Ringed seal grey seal cod herring and salmon may also be found in the bay In the 16th century seals were hunted in the Bay of Bothnia Ringed seals were captured using nets in the inshore open water and were stalked and captured in their dens or at breathing holes Both grey and ringed seals were hunted along the edge of the ice Wild vendace roe harvested from the Kalix River known as Kalix Lojrom or as sea gold is a delicacy with a European protected designation of origin Birdlife includes the black guillemot velvet scoter oystercatcher lesser black backed gull western capercaillie and willow ptarmigan Moose and hare are found on the islands as on the mainland Occasionally whales have been observed in the Bothnian Sea and remains of extinct Atlantic gray whale was found from Graso while it is not clear whether or not whales might once have reached Bothnian Bay historically PopulationOld Raahe FinlandIndustrial zone in Lulea Ports on the Finnish side include Haukipudas Jakobstad Kemi Kokkola Oulu Raahe and Tornio The largest towns by population on the Finnish side as of 2013 were Oulu 192 680 Tornio 22 374 Kemi 22 157 Kempele 16 549 Raahe 25 641 Kalajoki 12 637 Kokkola 46 697 and Jakobstad 19 636 In Finland the catchment area included about 544 000 hectares 1 340 000 acres of arable land as of 1993 There were four Finnish pulp and paper mills of which two Veitsiluoto Oy and Metsa Botnia Oy were producing bleached kraft paper On the Swedish side ports include Haparanda Karlsborg Kalix Lulea Pitea and Skelleftea The largest towns on the Swedish side as of 2013 were Lulea 74 000 Skelleftea 71 641 Pitea 40 860 and Kalix 16 926 Lulea is the largest city in Norrbotten with the largest airport The 1 312 islands of the Lulea archipelago are an important tourist attraction as is the Gammelstad church village listed as a Unesco World Heritage site As of 1993 there were about 113 000 hectares 280 000 acres of arable land in the Swedish part of the catchment basin mostly used for small scale low intensity farming There were five pulp and paper mills of which one produced bleached kraft paper In the late 1960s the bay was being used to transport fuel oil to the Finnish settlements around the bay In 1968 about 950 000 tons of cellulose and 230 600 tons of paper and cardboard were exported a figure that was rising In 1968 ships calling at the Finnish ports carried about 388 872 tons of iron bars and 64 326 tons of steel sheets Mining and mineral products such as coal and ore were carried to and from the ports and steel products were exported Sea transport continued throughout the winter In 1993 there were two non ferrous heavy metal smelters in Ronnskar and Kokkola emitting significant quantities of heavy metals Efforts were being made to reduce emissions The drainage basin also held three iron and steel plants and a number of mines Human activities have affected the fragile sub arctic environment Dredging and other activities related to sea transport affect marine life Agriculture forestry and peat mining in the catchment basin add nutrients to the bay affecting the ecological balance while pollutants are delivered from steel mills and from pulp and paper mills around the bay as well as from sewage treatment plants Steel mills and stainless steel plants may have released nickel and chromium Efforts have been made to reduce pollution through improved technology but some areas along the Finnish coastline show evidence of eutrophication Compared to other parts of the Baltic higher levels of nitrate have been found in the Bothnian Bay and lower levels of phosphate and silicates GalleryThe bridge to Seskaro Sweden Finnish icebreaker MSV Fennica in the Bay Looking back from the Icebreaker Sampo near Kemi Finland Outokumpu mill in Tornio Old mill buildings and harbour in Toppila Oulu Finland Buildings and the birdwatching tower at Varessaikka harbour Siikajoki Finland Old fisherman s cottage Lonkytin island The island of Kahvankari in Oulu Finland The eastern shore of the Kellon Kraaseli island Haukipudas Finland Bothnian Bay in Kemi Finland Sunset at Hiekkasarkat Kalajoki FinlandReferencesCitations Lepparanta amp Myrberg 2009 p 55 Szefer 2002 p 11 Baltic Sea Joint Comprehensive Environmental Action pp 2 3 Lepparanta amp Myrberg 2009 p 56 Merikartta Perameri osa 57 Roed 2011 Lepparanta amp Myrberg 2009 p 11 Nesje 2006 About the Bay Bottenvikens skargard Tikkanen Matti Oksanen Juha 2002 Late Weichselian and Holocene shore displacement history of the Baltic Sea in Finland Fennia 180 1 2 Retrieved 22 December 2017 Eleftheriou Smith amp Ansell 1995 p 23 Muller 1982 p 8 Eleftheriou Smith amp Ansell 1995 p 24 Makinen 1972 p 3 Ankre 2005 p 8 Index bottenviken se Sweden Rough Guides 2003 p 403 Haparanda Skargard National Park Bay of Bothnia National Park Statistik fran vader och vatten Manads och arsstatistik in Swedish Swedish Meteorological and Hydrological Institute Archived from the original on 2 May 2019 Retrieved 31 May 2021 SMHI Open Data for Lulea in Swedish Swedish Meteorological and Hydrological Institute Archived from the original on 11 April 2019 Retrieved 31 May 2021 SMHI Open Data in Swedish Swedish Meteorological and Hydrological Institute SMHI Open Data in Swedish SMHI 17 April 2021 SMHI Open Data in Swedish Swedish Meteorological and Hydrological Institute Archived from the original on 11 April 2019 Retrieved 10 March 2021 SMHI Average Monthly Data 2002 2018 in Swedish Swedish Meteorological and Hydrological Institute Archived from the original on 2 May 2019 Retrieved 10 March 2021 FMI normals 1981 2010 PDF FMI Retrieved 26 April 2016 FMI open data FMI Retrieved 7 September 2019 Suomen maakuntien ilmasto PDF helda helsinki fi in Finnish Retrieved 4 September 2023 Bottniska viken Stockholms universitets Eleftheriou Smith amp Ansell 1995 p 25 Eleftheriou Smith amp Ansell 1995 p 26 Eleftheriou Smith amp Ansell 1995 p 33 Eleftheriou Smith amp Ansell 1995 p 29 Kvist 1991 p 339 Swedish Lapland The destination Yle Uutiset 2006 Humpback Whale Spotted in Gulf of Bothnia Retrieved on September 05 2017 Jones L M Swartz L S Leatherwood S The Gray Whale Eschrichtius Robustus Eastern Atlantic Specimens pp 41 44 Academic Press Retrieved on September 05 2017 Bothnian Bay Port Map Vaestotietojarjestelma Rekisteritilanne Makinen 1972 p 4 Makinen 1972 p 5 Laine 2013 p 1 Szefer 2002 p 134 Wikimedia Commons has media related to Bothnian Bay Sources About the Bay of Bothnia Bottenvikens skargard Archived from the original on 5 October 2013 Retrieved 30 September 2013 Ankre Rosemarie 2005 A Case Study of the Lulea archipelago Sweden PDF Mid Sweden University Retrieved 4 October 2013 Baltic Sea Joint Comprehensive Environmental Action Programme Helsinki Balt Sea Environ Proc No 48 1993 Archived from the original on 3 March 2016 Retrieved 2 October 2013 Bay of Bothnia National Park Lapland Travel Info Archived from the original on 4 September 2014 Retrieved 30 September 2013 Bothnian Bay Port Map World Port Source Archived from the original on 5 October 2013 Retrieved 1 October 2013 Bottniska viken Havet nu Stockholms universitets Ostersjocentrum and Umea marina forskningscentrum Retrieved 30 September 2013 Eleftheriou Anastasios Smith Christopher Ansell Alan D 1995 Biology and Ecology of Shallow Coastal Waters Proceedings of the 28th European Marine Biology Symposium Institute of Marine Biology of Crete Iraklio Crete 1993 Olsen amp Olsen ISBN 978 87 85215 28 4 Retrieved 30 September 2013 Haparanda Skargard National Park Swedish Environmental Protection Agency Retrieved 2 October 2013 Index bottenviken se Retrieved 2 October 2013 Kvist Roger October 1991 Sealing and sealing methods in the Bay of Bothnia 1551 70 Polar Record 27 163 339 344 doi 10 1017 s0032247400013097 ISSN 1475 3057 S2CID 129763552 Laine Anne 2013 Bothnian Bay Life Integrated Management System for the Bothnian Bay Retrieved 2 October 2013 Lepparanta Matti Myrberg Kai 20 March 2009 Physical Oceanography of the Baltic Sea Springer p 55 ISBN 978 3 540 79703 6 Retrieved 1 October 2013 Makinen Pentti September 1972 Winter Navigation in the Bothnian Bay and the Iceworthiness of Merchant Vessels PDF U S Department of Commerce Retrieved 2 October 2013 Merikartta Perameri osa 57 Nautical chart of the Bay of Bothnia 57 Muller K 30 April 1982 Coastal Research in the Gulf of Bothnia Springer ISBN 978 90 6193 098 3 Retrieved 30 September 2013 Nesje Atle 30 May 2006 Isbreene smelter havnivaet stiger CICERO Archived from the original on 20 June 2013 Retrieved 18 August 2012 Nordstrom Marie 4 December 2009 Perameri Bothnian Bay Life project Archived from the original on 28 September 2005 Retrieved 30 September 2013 Roed Lars Ludvig 4 November 2011 Norge blir stadig hoyere Aftenposten Sweden Rough Guides 2003 ISBN 978 1 84353 066 4 Retrieved 2 October 2013 Swedish Lapland The destination Swedish Lapland DMC Archived from the original on 29 March 2016 Retrieved 2 October 2013 Szefer P 30 January 2002 Metals Metalloids and Radionuclides in the Baltic Sea Ecosystem Elsevier ISBN 978 0 08 053633 0 Retrieved 30 September 2013 Vaestotietojarjestelma Rekisteritilanne in Finnish and Swedish Population Register Center of Finland 31 August 2013 Archived from the original on 28 September 2013 Retrieved 2 October 2013
