Sea is a sea of the Atlantic Ocean, enclosed by
Scandinavia, Finland, Estonia, Latvia, Lithuania, Russia, Poland,
Germany and the North and Central European Plain.
The sea stretches from 53°N to 66°N latitude and from 10°E to 30°E
longitude. A mediterranean sea of the Atlantic, with limited water
exchange between the two bodies, the Baltic
Sea drains through the
Danish islands into the
Kattegat by way of the straits of Øresund,
the Great Belt, and the Little Belt. It includes the Gulf of Bothnia,
the Bay of Bothnia, the Gulf of Finland, the Gulf of Riga, and the Bay
Baltic Proper is bordered on its northern edge, at the latitude
60°N, by the
Åland islands and the Gulf of Bothnia, on its
northeastern edge by the Gulf of Finland, on its eastern edge by the
Gulf of Riga, and in the west by the Swedish part of the southern
Sea is connected by artificial waterways to the White Sea
via the White
Sea Canal and to the
German Bight of the North
2.1 Name in other languages
3.1 Classical world
3.2 Middle Ages
3.3 An arena of conflict
3.4 Since World War II
3.5 Storm floods
4.1 Geophysical data
4.4 The ice
4.7 Major tributaries
4.8 Islands and archipelagoes
4.9 Coastal countries
5.1 The "Baltic
6.2 Environmental status
8.1 1974 Convention
8.2 1992 Convention
9 See also
11 External links
Danish Straits and southwestern Baltic Sea
Helsinki Convention on the Protection of the Marine Environment of
Sea Area includes the Baltic
Sea and the Kattegat, without
Kattegat a part of the Baltic Sea, "For the purposes of this
Convention the "Baltic
Sea Area" shall be the Baltic
Sea and the
Entrance to the Baltic Sea, bounded by the parallel of the Skaw in the
Skagerrak at 57°44.43'N."
Historically, the Kingdom of
Sound Dues from ships
at the border between the ocean and the land-locked Baltic Sea. They
were collected in the
Kronborg castle near Helsingør, in
Great Belt at Nyborg. In the Little Belt, the site of intake was
moved to Fredericia, after that stronghold had been built. The
narrowest part of
Little Belt is the "
Middelfart Sund" near
Geographers widely agree that the preferred physical border of the
Baltic is a line drawn through the southern Danish islands,
Drogden-Sill and Langeland. The
Drogden Sill is situated north of
Køge Bugt and connects
Dragør in the south of
Copenhagen to Malmö;
it is used by the
Øresund Bridge, including the
Drogden Tunnel. By
this definition, the
Danish Straits are part of the entrance, but the
Bay of Mecklenburg
Bay of Mecklenburg and the Bay of
Kiel are parts of the Baltic Sea.
Another usual border is the line between Falsterbo,
Sweden and Stevns
Klint, Denmark, as this is the southern border of Øresund. It's also
the border between the shallow southern
Øresund (with a typical depth
of 5–10 meters only) and notably deeper water.
Hydrography and biology
Drogden Sill (depth of 7 m (23 ft)) sets a limit to Øresund
Darss Sill (depth of 18 m (59 ft)), and a limit to the
Belt Sea. The shallow sills are obstacles to the flow of heavy salt
water from the
Kattegat into the basins around
Bornholm and Gotland.
Kattegat and the southwestern Baltic
Sea are well oxygenated and
have a rich biology. The remainder of the
Sea is brackish, poor in
oxygen and in species. Thus, statistically, the more of the entrance
that is included in its definition, the healthier the Baltic appears;
conversely, the more narrowly it is defined, the more endangered its
Tacitus called it Mare Suebicum after the
Germanic people of the
Ocean after the Sarmatians, the
first to name it the Baltic
Sea (Mare Balticum) was the
eleventh-century German chronicler Adam of Bremen. The origin of the
latter name is speculative and it was adopted into Slavic and Finnic
languages spoken around the sea, very likely due to the role of
Medieval Latin in cartography. It might be connected to the Germanic
word belt, a name used for two of the Danish straits, the Belts, while
others claim it to be directly derived from the source of the Germanic
Latin balteus "belt".
Adam of Bremen
Adam of Bremen himself compared the sea
with a belt, stating that it is so named because it stretches through
the land as a belt (Balticus, eo quod in modum baltei longo tractu per
Scithicas regiones tendatur usque in Greciam).
He might also have been influenced by the name of a legendary island
mentioned in the Natural History of Pliny the Elder. Pliny mentions an
Baltia (or Balcia) with reference to accounts of Pytheas
and Xenophon. It is possible that Pliny refers to an island named
Basilia ("the royal") in On the
Ocean by Pytheas.
Baltia also might be
derived from belt and mean "near belt of sea, strait."
Meanwhile, others have suggested that the name of the island
originates from the Proto-Indo-European root *bhel meaning "white,
fair". This root and its basic meaning were retained in both
Lithuanian (as baltas) and Latvian (as balts). On this basis, a
related hypothesis holds that the name originated from this
Indo-European root via a
Baltic language such as Lithuanian.
Another explanation is that, while derived from the aforementioned
root, the name of the sea is related to names for various forms of
water and related substances in several European languages, that might
have been originally associated with colors found in swamps (compare
Proto-Slavic *bolto "swamp"). Yet another explanation is that the name
originally meant "enclosed sea, bay" as opposed to open sea. Some
Swedish historians believe the name derives from the god
Middle Ages the sea was known by a variety of names. The name
Sea became dominant only after 1600. Usage of Baltic and
similar terms to denote the region east of the sea started only in
Name in other languages
Sea was known in ancient
Latin language sources as Mare
Suebicum or even Mare Germanicum. Older native names in languages
that used to be spoken on the shores of the sea or near it usually
indicate the geographical location of the sea (in Germanic languages),
or its size in relation to smaller gulfs (in Old Latvian), or tribes
associated with it (in Old Russian the sea was known as the Varanghian
Sea). In modern languages it is known by the equivalents of "East
Sea", "West Sea", or "Baltic Sea" in different languages:
"Baltic Sea" is used in English; in the
Baltic languages Latvian
(Baltijas jūra; in Old Latvian it was referred to as "the Big Sea",
while the present day Gulf of
Riga was referred to as "the Little
Sea") and Lithuanian (Baltijos jūra); in
Latin (Mare Balticum) and
Romance languages French (Mer Baltique), Italian (Mar Baltico),
Portuguese (Mar Báltico), Romanian (Marea Baltică) and Spanish (Mar
Báltico); in Greek (Βαλτική Θάλασσα Valtikí
Thálassa); in Albanian (Deti Balltik); in Welsh (Môr Baltig); in the
Slavic languages Polish (Morze Bałtyckie or Bałtyk), Czech (Baltské
moře or Balt), Slovenian (Baltsko morje), Bulgarian
(Балтийско море Baltijsko More), Kashubian (Bôłt),
Macedonian (Балтичко Море Baltičko More), Ukrainian
(Балтійське море Baltijs′ke More), Belarusian
(Балтыйскае мора Baltyjskaje Mora), Russian
(Балтийское море Baltiyskoye More) and Serbo-Croatian
(Baltičko more / Балтичко море); in Hungarian
In Germanic languages, except English, "East Sea" is used, as in
Afrikaans (Oossee), Danish (Østersøen), Dutch (Oostzee), German
(Ostsee), Icelandic and Faroese (Eystrasalt), Norwegian
(Østersjøen), and Swedish (Östersjön). In
Old English it was known
as Ostsæ; also in Hungarian the former name was Keleti-tenger (due to
German influence). In addition, Finnish, a Finnic language, has
calqued the Swedish term as Itämeri "East Sea", disregarding the
geography (the sea is west of Finland), though understandably since
Finland was a part of
Sweden from the
Middle Ages until 1809.
In another Finnic language, Estonian, it is called the "West Sea"
(Läänemeri), with the correct geography (the sea is west of
At the time of the Roman Empire, the Baltic
Sea was known as the Mare
Suebicum or Mare Sarmaticum.
Tacitus in his AD 98 Agricola and
Germania described the Mare Suebicum, named for the
during the spring months, as a brackish sea where the ice broke apart
and chunks floated about. The
Suebi eventually migrated southwest to
reside for a while in the Rhineland area of modern Germany, where
their name survives in the historic region known as Swabia. Jordanes
called it the Germanic
Sea in his work, the Getica.
Cape Arkona on the island of
Rügen in Germany, was a sacred site of
the Slavs before Christianization.
In the early Middle Ages, Norse (Scandinavian) merchants built a trade
empire all around the Baltic. Later, the Norse fought for control of
the Baltic against Wendish tribes dwelling on the southern shore. The
Norse also used the rivers of
Russia for trade routes, finding their
way eventually to the Black
Sea and southern Russia. This
Norse-dominated period is referred to as the Viking Age.
Since the Viking age, the Scandinavians have referred to the Baltic
Sea as Austmarr ("Eastern Lake"). "Eastern Sea", appears in the
Heimskringla and Eystra salt appears in Sörla þáttr. Saxo
Grammaticus recorded in
Gesta Danorum an older name, Gandvik, -vik
Old Norse for "bay", which implies that the Vikings correctly
regarded it as an inlet of the sea. Another form of the name,
"Grandvik", attested in at least one English translation of Gesta
Danorum, is likely to be a misspelling.)
In addition to fish the sea also provides amber, especially from its
southern shores within today's borders of Poland,
Lithuania. First mentions of amber deposits on the South coast of the
Sea date back to the 12th century. The bordering countries
have also traditionally exported lumber, wood tar, flax, hemp and furs
by ship across the Baltic.
Sweden had from early medieval times
exported iron and silver mined there, while
Poland had and still has
extensive salt mines. Thus the Baltic
Sea has long been crossed by
much merchant shipping.
The lands on the Baltic's eastern shore were among the last in Europe
to be converted to Christianity. This finally happened during the
Finland in the twelfth century by Swedes, and what
Latvia in the early thirteenth century by Danes
and Germans (Livonian Brothers of the Sword). The Teutonic Order
gained control over parts of the southern and eastern shore of the
Baltic Sea, where they set up their monastic state.
Lithuania was the
last European state to convert to Christianity.
An arena of conflict
Main trading routes of the
Hanseatic League (Hanse).
In 1649 the settlement of the Latvian-speaking
Kursenieki spanned from
Gdańsk along the coast of the Baltic Sea.
In the period between the 8th and 14th centuries, there was much
piracy in the Baltic from the coasts of
Pomerania and Prussia, and the
Victual Brothers even held Gotland.
Starting in the 11th century, the southern and eastern shores of the
Baltic were settled by migrants mainly from Germany, a movement called
Ostsiedlung ("east settling"). Other settlers were from the
Netherlands, Denmark, and Scotland. The
Polabian Slavs were gradually
assimilated by the Germans.
Denmark gradually gained control over
most of the Baltic coast, until she lost much of her possessions after
being defeated in the 1227 Battle of Bornhöved.
Battle of the Sound
Battle of the Sound took place on 8 November 1658 during the
Cap Arcona shortly after the attacks, 3 May 1945. Only 350
survived of the 4,500 prisoners who had been aboard
In the 13th to 16th centuries, the strongest economic force in
Europe was the Hanseatic League, a federation of merchant
cities around the Baltic
Sea and the North Sea. In the sixteenth and
early seventeenth centuries, Poland, Denmark, and
Sweden fought wars
Dominium maris baltici
Dominium maris baltici ("Lordship over the Baltic Sea").
Eventually, it was
Sweden that virtually encompassed the Baltic Sea.
Sweden the sea was then referred to as Mare Nostrum Balticum ("Our
Baltic Sea"). The goal of Swedish warfare during the 17th century was
to make the Baltic
Sea an all-Swedish sea (Ett Svenskt innanhav),
something that was accomplished except the rout[clarification needed]
Latvia and Stettin in Pomerania. However, it was the
Dutch who dominated Baltic trade in the seventeenth century.
In the eighteenth century,
Prussia became the leading
powers over the sea. Sweden's defeat in the
Great Northern War
Great Northern War brought
Russia to the eastern coast.
Russia became and remained a dominating
power in the Baltic. Russia's
Peter the Great
Peter the Great saw the strategic
importance of the Baltic and decided to found his new capital, Saint
Petersburg, at the mouth of the
Neva river at the east end of the Gulf
of Finland. There was much trading not just within the Baltic region
but also with the North
Sea region, especially eastern
England and the
Netherlands: their fleets needed the Baltic timber, tar, flax and
During the Crimean War, a joint British and French fleet attacked the
Russian fortresses in the Baltic. They bombarded Sveaborg, which
guards Helsinki; and Kronstadt, which guards Saint Petersburg; and
they destroyed Bomarsund in the Åland Islands. After the unification
Germany in 1871, the whole southern coast became German. World War
I was partly fought in the Baltic Sea. After 1920
Poland was connected
to the Baltic
Sea by the
Polish Corridor and enlarged the port of
Gdynia in rivalry with the port of the Free City of Danzig.
During World War II,
Germany reclaimed all of the southern and much of
the eastern shore by occupying
Poland and the Baltic states. In 1945,
Sea became a mass grave for retreating soldiers and
refugees on torpedoed troop transports. The sinking of the Wilhelm
Gustloff remains the worst maritime disaster in history, killing (very
roughly) 9,000 people. In 2005, a Russian group of scientists found
over five thousand airplane wrecks, sunken warships, and other
material, mainly from World War II, on the bottom of the sea.
Since World War II
Since the end of World War II, various nations, including the Soviet
United Kingdom and the United States, have disposed of
chemical weapons in the Baltic Sea, raising concerns of environmental
contamination. Even now fishermen accidentally retrieve some of
these materials: the most recent available report from the Helsinki
Commission notes that four small scale catches of chemical munitions
representing approximately 105 kg (231 lb) of material were
reported in 2005. This is a reduction from the 25 incidents
representing 1,110 kg (2,450 lb) of material in 2003.
Until now, the
U.S. Government refuses to disclose the exact
coordinates of the wreck sites. Rotting bottles leak Lost and other
substances, thus slowly poisoning a substantial part of the Baltic
After 1945, the German population was expelled from all areas east of
the Oder-Neisse line, making room for displaced Poles and Russians.
Poland gained most of the southern shore. The
Soviet Union gained
another access to the Baltic with the
Kaliningrad Oblast. The Baltic
states on the eastern shore were annexed by the Soviet Union. The
Baltic then separated opposing military blocs:
NATO and the Warsaw
Pact. Had war broken out, the Polish navy was prepared to invade the
Danish isles. This border status restricted trade and travel. It ended
only after the collapse of the
Communist regimes in Central and
Europe in the late 1980s.
Since May 2004, with the accession of the
Baltic states and Poland,
Sea has been almost entirely surrounded by countries of the
European Union (EU). The only remaining non-EU shore areas are
Saint Petersburg area and the exclave of the Kaliningrad
Winter storms begin arriving in the region during October. These have
caused numerous shipwrecks, and contributed to the extreme
difficulties of rescuing passengers of the ferry M/S
Estonia en route
from Tallinn, Estonia, to Stockholm, Sweden, in September 1994, which
claimed the lives of 852 people. Older, wood-based shipwrecks such as
the Vasa tend to remain well-preserved, as the Baltic's cold and
brackish water does not suit the shipworm.
Storm surge floodings are generally taken to occur when the water
level is more than one metre above normal. In Warnemünde about 110
floods occurred from 1950 to 2000, an average of just over two per
Historic flood events were the
All Saints' Flood of 1304
All Saints' Flood of 1304 and other
floods in the years 1320, 1449, 1625, 1694, 1784 and 1825. Little is
known of their extent. From 1872, there exist regular and reliable
records of water levels in the Baltic Sea. The highest was the flood
of 1872 when the water was an average of 2.43 m (8 ft
0 in) above sea level at Warnemünde and a maximum of 2.83 m
(9 ft 3 in) above sea level in Warnemünde. In the last very
heavy floods the average water levels reached 1.88 m (6 ft
2 in) above sea level in 1904, 1.89 m (6 ft 2 in)
in 1913, 1.73 m (5 ft 8 in) in January 1954,
1.68 m (5 ft 6 in) on 2–4 November 1995 and
1.65 m (5 ft 5 in) on 21 February 2002.
Baltic drainage basins (catchment area), with depth, elevation, major
rivers and lakes
Curonian Spit in
Kaliningrad Oblast, Russia
An arm of the North Atlantic Ocean, the Baltic
Sea is enclosed by
Denmark to the northwest,
Finland to the northeast, the
Baltic countries to the southeast, and the
North European Plain
North European Plain to the
It is about 1,600 km (990 mi) long, an average of
193 km (120 mi) wide, and an average of 55 metres
(180 ft) deep. The maximum depth is 459 m (1,506 ft)
which is on the Swedish side of the center. The surface area is about
349,644 km2 (134,998 sq mi)  and the volume is
about 20,000 km3 (4,800 cu mi). The periphery amounts
to about 8,000 km (5,000 mi) of coastline.
Sea is one of the largest brackish inland seas by area, and
occupies a basin (a zungenbecken) formed by glacial erosion during the
last few ice ages.
Physical characteristics of the Baltic Sea, its main sub-regions, and
the transition zone to the Skagerrak/North
1. Baltic proper
2. Gulf of Bothnia
3. Gulf of Finland
4. Gulf of Riga
5. Belt Sea/Kattegat
Total Baltic Sea
International Hydrographic Organization
International Hydrographic Organization defines the limits of the
Sea as follows:
Bordered by the coasts of Germany, Denmark, Poland, Sweden, Finland,
Latvia and Lithuania, it extends north-eastward of
the following limits:
In the Little Belt. A line joining Falshöft (54°47′N
9°57.5′E / 54.783°N 9.9583°E / 54.783; 9.9583) and
Vejsnæs Nakke (Ærø: 54°49′N 10°26′E / 54.817°N
10.433°E / 54.817; 10.433).
In the Great Belt. A line joining Gulstav (South extreme of Langeland
Island) and Kappel Kirke (54°46′N 11°01′E / 54.767°N
11.017°E / 54.767; 11.017) on Island of Lolland.
In the Guldborg Sound. A line joining Flinthorne-Rev and Skjelby
(54°38′N 11°53′E / 54.633°N 11.883°E / 54.633;
In the Sound. A line joining Stevns Lighthouse (55°17′N
12°27′E / 55.283°N 12.450°E / 55.283; 12.450) and
Falsterbo Point (55°23′N 12°49′E / 55.383°N 12.817°E
/ 55.383; 12.817).
Regions and basins of the Baltic Sea:
1 = Bothnian Bay
2 = Bothnian Sea
1 + 2 = Gulf of Bothnia, partly also 3 & 4
4 = Åland Sea
5 = Gulf of Finland
6 = Northern Baltic Proper
7 = Western
8 = Eastern
9 = Gulf of Riga
10 = Bay of Gdańsk/Gdansk Basin
Bornholm Basin and Hanö Bight
12 = Arkona Basin
6–12 = Baltic Proper
13 = Kattegat, not an integral part of the Baltic Sea
14 = Belt
Little Belt and Great Belt)
Öresund (The Sound)
14 + 15 = Danish Straits, not an integral part of the Baltic Sea
The northern part of the Baltic
Sea is known as the Gulf of Bothnia,
of which the northernmost part is the
Bay of Bothnia
Bay of Bothnia or Bothnian Bay.
The more rounded southern basin of the gulf is called Bothnian
immediately to the south of it lies the
Sea of Åland. The Gulf of
Finland connects the Baltic
Sea with Saint Petersburg. The Gulf of
Riga lies between the Latvian capital city of
Riga and the Estonian
island of Saaremaa.
The Northern Baltic
Sea lies between the
Stockholm area, southwestern
Finland and Estonia. The Western and Eastern
Gotland Basins form the
major parts of the Central Baltic
Sea or Baltic proper. The Bornholm
Basin is the area east of Bornholm, and the shallower Arkona Basin
Bornholm to the Danish isles of
Falster and Zealand.
In the south, the Bay of
Gdańsk lies east of the
Hel Peninsula on the
Polish coast and west of the
Sambia Peninsula in
The Bay of
Pomerania lies north of the islands of
Usedom and Wolin,
east of Rügen. Between
Falster and the German coast lie the Bay of
Mecklenburg and Bay of Lübeck. The westernmost part of the Baltic Sea
is the Bay of Kiel. The three Danish straits, the Great Belt, the
Little Belt and The Sound (Öresund/Øresund), connect the Baltic Sea
Skagerrak strait in the North Sea.
Satellite image of the Baltic
Sea in a mild winter
Sea and ice
On the long-term average, the Baltic
Sea is ice-covered at the annual
maximum for about 45% of its surface area. The ice-covered area during
such a typical winter includes the Gulf of Bothnia, the Gulf of
Finland, the Gulf of Riga, the archipelago west of Estonia, the
Stockholm archipelago, and the
Sea southwest of Finland.
The remainder of the Baltic does not freeze during a normal winter,
with the exception of sheltered bays and shallow lagoons such as the
Curonian Lagoon. The ice reaches its maximum extent in February or
March; typical ice thickness in the northernmost areas in the Bothnian
Bay, the northern basin of the Gulf of Bothnia, is about 70 cm
(28 in) for landfast sea ice. The thickness decreases farther
Freezing begins in the northern extremities of Gulf of Bothnia
typically in the middle of November, reaching the open waters of the
Bothnian Bay in early January. The Bothnian Sea, the basin south of
Kvarken, freezes on average in late February. The Gulf of
the Gulf of
Riga freeze typically in late January. In 2011, the Gulf
Finland was completely frozen on 15 February.
The ice extent depends on whether the winter is mild, moderate, or
severe. Severe winters can lead to ice formation around southern
Sweden and even in the Danish straits. According to the 18th-century
natural historian William Derham, during the severe winters of 1703
and 1708, the ice cover reached as far as the Danish straits.
Frequently, parts of the
Gulf of Bothnia
Gulf of Bothnia and Gulf of
frozen, in addition to coastal fringes in more southerly locations
such as the Gulf of Riga. This description meant that the whole of the
Sea was covered with ice.
It is known that since 1720, the Baltic
Sea has frozen over entirely a
total of 20 times. The most recent case was in early 1987, which was
the most severe winter in
Scandinavia since that date. The ice then
covered 400,000 km2 (150,000 sq mi). During the winter
of 2010–11, which was quite severe compared to those of the last
decades, the maximum ice cover was 315,000 km2
(122,000 sq mi), which was reached on 25 February 2011. The
ice then extended from the north down to the northern tip of Gotland,
with small ice-free areas on either side, and the east coast of the
Sea was covered by an ice sheet about 25 to 100 km (16 to
62 mi) wide all the way to Gdańsk. This was brought about by a
stagnant high-pressure area that lingered over central and northern
Scandinavia from around 10 to 24 February. After this, strong southern
winds pushed the ice further into the north, and much of the waters
Gotland were again free of ice, which had then packed against
the shores of southern Finland. The effects of the afore-mentioned
high-pressure area did not reach the southern parts of the Baltic Sea,
and thus the entire sea did not freeze over. However, floating ice was
additionally observed near
Świnoujście harbour in January 2010.
In recent years prior to 2011, the
Bothnian Bay and the Bothnian Sea
were frozen with solid ice near the Baltic coast and dense floating
ice far from it. In 2008, there was almost no ice formation except for
a short period in March.
Piles of drift ice on the shore of Puhtulaid, near Virtsu, Estonia, in
During winter, fast ice, which is attached to the shoreline, develops
first, rendering ports unusable without the services of icebreakers.
Level ice, ice sludge, pancake ice, and rafter ice form in the more
open regions. The gleaming expanse of ice is similar to the Arctic,
with wind-driven pack ice and ridges up to 15 m (49 ft).
Offshore of the landfast ice, the ice remains very dynamic all year,
and it is relatively easily moved around by winds and therefore forms
pack ice, made up of large piles and ridges pushed against the
landfast ice and shores.
In spring, the Gulf of
Finland and the
Gulf of Bothnia
Gulf of Bothnia normally thaw
in late April, with some ice ridges persisting until May in the
eastern extremities of the Gulf of Finland. In the northernmost
reaches of the Bothnian Bay, ice usually stays until late May; by
early June it is practically always gone. However, in the famine year
of 1867 remnants of ice were observed as late as July 17 near
Uddskär. Even as far south as Øresund, remnants of ice have been
observed in May on several occasions; near
Taarbaek on May 15, 1942
Copenhagen on May 11, 1771. Drift ice was also observed on
May 11, 1799.
The ice cover is the main habitat for two large mammals, the grey seal
(Halichoerus grypus) and the Baltic ringed seal (Pusa hispida
botnica), both of which feed underneath the ice and breed on its
surface. Of these two seals, only the Baltic ringed seal suffers when
there is not adequate ice in the Baltic Sea, as it feeds its young
only while on ice. The grey seal is adapted to reproducing also with
no ice in the sea. The sea ice also harbours several species of algae
that live in the bottom and inside unfrozen brine pockets in the ice.
Depths of the Baltic
Sea in metres
Sea flows out through the Danish straits; however, the flow
is complex. A surface layer of brackish water discharges 940 km3
(230 cu mi) per year into the North Sea. Due to the
difference in salinity, by salinity permeation principle, a
sub-surface layer of more saline water moving in the opposite
direction brings in 475 km3 (114 cu mi) per year. It
mixes very slowly with the upper waters, resulting in a salinity
gradient from top to bottom, with most of the salt water remaining
below 40 to 70 m (130 to 230 ft) deep. The general
circulation is anti-clockwise: northwards along its eastern boundary,
and south along the western one .
The difference between the outflow and the inflow comes entirely from
fresh water. More than 250 streams drain a basin of about
1,600,000 km2 (620,000 sq mi), contributing a volume of
660 km3 (160 cu mi) per year to the Baltic. They
include the major rivers of north Europe, such as the Oder, the
Vistula, the Neman, the Daugava and the Neva. Additional fresh water
comes from the difference of precipitation less evaporation, which is
An important source of salty water are infrequent inflows of North Sea
water into the Baltic. Such inflows, important to the Baltic ecosystem
because of the oxygen they transport into the Baltic deeps, used to
happen on average every four to five years until the 1980s. In recent
decades they have become less frequent. The latest four occurred in
1983, 1993, 2003 and 2014 suggesting a new inter-inflow period of
about ten years.
The water level is generally far more dependent on the regional wind
situation than on tidal effects. However, tidal currents occur in
narrow passages in the western parts of the Baltic Sea.
The significant wave height is generally much lower than that of the
North Sea. Violent and sudden storms often sweep the surface, due to
large transient temperature differences and a long reach of wind.
Seasonal winds also cause small changes in sea level, of the order of
0.5 m (1 ft 8 in) .
The Baltic Sea's salinity is much lower than that of ocean water
(which averages 3.5%), as a result of abundant freshwater runoff from
the surrounding land, combined with the shallowness of the sea itself;
runoff contributes roughly one-fortieth its total volume per year, as
the volume of the basin is about 21,000 km3
(5,000 cu mi) and yearly runoff is about 500 km3
(120 cu mi). The open surface waters of the central basin
have salinity of 0.5% to 0.8%, which makes the basin border-line
freshwater. Drinking the water as a means of survival would actually
hydrate the body instead of dehydrating, as is the case with ocean
water.[note 1] At the semi-enclosed bays with major freshwater
inflows, such as the head of Finnish Gulf with the
Neva mouth and the
head of the
Bothnian Gulf with the close mouths of the Lule, Tornio
and Kemi, the salinity is considerably lower. Below 40 to 70 m
(130 to 230 ft), the salinity is between 1.0% and 1.5% in the
open Baltic Sea, and higher near the Danish Straits, but this is still
less than half that of ocean water.
The flow of fresh water into the sea from approximately two hundred
rivers and the introduction of salt from the South builds up a
gradient of salinity in the Baltic Sea. Near the
Danish straits the
salinity is close to that of the Kattegat, but still not fully
oceanic, because the saltiest water that passes the straits is already
mixed with considerable amounts of outflow water. The salinity
steadily decreases towards North and East. At the northern part of the
Gulf of Bothnia
Gulf of Bothnia the water is no longer salty and many fresh water
species live in the sea. The salinity gradient is paralleled by a
temperature gradient. These two factors limit many species of animals
and plants to a relatively narrow region of the Baltic Sea.
The most saline water is vertically stratified in the water column to
the north, creating a barrier to the exchange of oxygen and nutrients,
and fostering completely separate maritime environments.
See also: List of rivers of the Baltic Sea
The rating of mean discharges differs from the ranking of hydrological
lengths (from the most distant source to the sea) and the rating of
the nominal lengths. Göta älv, a tributary of the Kattegat, is not
listed, as due to the northward upper low-salinity-flow in the sea,
its water hardly reaches the Baltic proper:
States sharing the basin
Finland (Ladoga-affluent Vuoksi)
Suna (280 km) →
Lake Onega (160 km) →
Svir (224 km) →
Lake Ladoga (122 km) → Neva
Poland, tributaries: Belarus, Ukraine, Slovakia
Russia (source), Latvia
Belarus (source), Lithuania, Russia
550 (main river)
600 (river system)
Norway (source of Ounasjoki)
longer tributary Kitinen
Czech Republic (source), Poland, Germany
Russia (Source of Velikaya), Estonia
Velikaya (430 km) →
Lake Peipus (145 km) → Narva
Norway (source), Sweden, Finland
Válfojohka → Kamajåkka → Abiskojaure → Abiskojokk
(total 40 km) →
Torneträsk (70 km) → Torne älv
Islands and archipelagoes
Main article: List of islands in the Baltic Sea
Skerries form an integral and typical part of many of the archipelagos
of the Baltic Sea, such as these in the archipelago of the Åland
Aerial view of Bornholm, Denmark
Åland Islands (Finland, autonomous)
Blekinge archipelago (Sweden)
Kvarken archipelago, including
Stockholm archipelago (Sweden)
Usedom or Uznam (split between
Germany and Poland)
West Estonian archipelago
West Estonian archipelago (Estonia):
Vast coastal dunes are characteristic for large parts of the southern
shore of the Baltic Sea.
Kuršių Nerija National Park
Kuršių Nerija National Park in Lithuania
(pictured) is a part of the
Curonian Spit World Heritage Site.
Population density in the Baltic
Sea catchment area
Countries that border the sea:
Denmark, Estonia, Finland, Germany,
Latvia, Lithuania, Poland, Russia,
Countries that are in the drainage basin but do not border the sea:
Belarus, Czech Republic, Norway, Slovakia,
The Baltic sea drainage basin is roughly four times the surface area
of the sea itself. About 48% of the region is forested, with Sweden
Finland containing the majority of the forest, especially around
the Gulfs of Bothnia and Finland.
About 20% of the land is used for agriculture and pasture, mainly in
Poland and around the edge of the Baltic Proper, in Germany, Denmark
and Sweden. About 17% of the basin is unused open land with another 8%
of wetlands. Most of the latter are in the Gulfs of Bothnia and
The rest of the land is heavily populated. About 85 million people
live in the Baltic drainage basin, 15 million within 10 km
(6 mi) of the coast and 29 million within 50 km (31 mi)
of the coast. Around 22 million live in population centers of over
250,000. 90% of these are concentrated in the 10 km (6 mi)
band around the coast. Of the nations containing all or part of the
Poland includes 45% of the 85 million,
and the others less than 6% each.
Tallinn in Estonia
Helsinki in Finland
Stockholm in Sweden
Vasilyevsky Island in Saint Petersburg, Russia
Main article: List of cities and towns around the Baltic Sea
The biggest coastal cities (by population):
Saint Petersburg (Russia) 4,700,000 (metropolitan area 6,000,000)
Stockholm (Sweden) 843,139 (metropolitan area 2,046,103)
Riga (Latvia) 696,567 (metropolitan area 842,000)
Helsinki (Finland) 605,022 (metropolitan area 1,358,901)
Gdańsk (Poland) 462,700 (metropolitan area 1,041,000)
Tallinn (Estonia) 435,245 (metropolitan area 542,983)
Kaliningrad (Russia) 431,500
Szczecin (Poland) 413,600 (metropolitan area 778,000)
Gdynia (Poland) 255,600 (metropolitan area 1,041,000)
Kiel (Germany) 242,000
Espoo (Finland) 257,195 (part of
Helsinki metropolitan area)
Lübeck (Germany) 216,100
Rostock (Germany) 212,700
Klaipėda (Lithuania) 194,400
Oulu (Finland) 191,050
Turku (Finland) 180,350
Other important ports:
Port of Naantali
Port of Naantali 18,789
Neustadt in Holstein
Neustadt in Holstein 16,000
Geology of the Baltic Sea
Ancylus Lake around 8700 years BP. The relic of Scandinavian Glacier
in white. The rivers Svea älv (Svea river) and
Göta älv formed an
outlet to the Atlantic.
Much of modern
Finland is former seabed or archipelago: illustrated
are sea levels immediately after the last ice age.
Evolution of the Baltic Sea
Sea (130,000–115,000 BP)
Ice sheets and seas (115,000–12,600 BP)
Baltic Ice Lake
Baltic Ice Lake (12,600–10,300 BP)
Sea (10,300–9,500 BP)
Ancylus Lake (9,500–8,000 BP)
Sea (8,000–7,500 BP)
Sea (7,500–4,000 BP)
Sea (4,000 BP–present)
Sea somewhat resembles a riverbed, with two tributaries,
the Gulf of
Finland and Gulf of Bothnia. Geological surveys show that
before the Pleistocene, instead of the Baltic Sea, there was a wide
plain around a great river paleontologists call the Eridanos. Several
Pleistocene glacial episodes scooped out the river bed into the sea
basin. By the time of the last, or
Eemian Stage (MIS 5e), the
Sea was in place. Instead of a true sea, the Baltic can even
today also be understood as the common estuary of all rivers flowing
From that time the waters underwent a geologic history summarized
under the names listed below. Many of the stages are named after
marine animals (e.g. the
Littorina mollusk) that are clear markers of
changing water temperatures and salinity.
The factors that determined the sea's characteristics were the
submergence or emergence of the region due to the weight of ice and
subsequent isostatic readjustment, and the connecting channels it
found to the North Sea-Atlantic, either through the straits of Denmark
or at what are now the large lakes of Sweden, and the White Sea-Arctic
Eemian Sea, 130,000–115,000 (years ago)
Baltic Ice Lake, 12,600–10,300
Yoldia Sea, 10,300–9500
Ancylus Lake, 9,500–8,000
Littorina Sea, 7,500–4,000
The land is still emerging isostatically from its depressed state,
which was caused by the weight of ice during the last glaciation. The
phenomenon is known as post-glacial rebound. Consequently, the surface
area and the depth of the sea are diminishing. The uplift is about
eight millimetres per year on the Finnish coast of the northernmost
Gulf of Bothnia. In the area, the former seabed is only gently
sloping, leading to large areas of land being reclaimed in what are,
geologically speaking, relatively short periods (decades and
Main article: Baltic
Sea anomaly" refers to interpretations of an indistinct
sonar image taken by Swedish salvage divers on the floor of the
Sea in June 2011. The treasure hunters suggested the
image showed an object with unusual features of seemingly
extraordinary origin. Speculation published in tabloid newspapers
claimed that the object was a sunken UFO. A consensus of experts and
scientists say that the image most likely shows a natural geological
See also: List of fish in Sweden
The fauna of the Baltic sea is a mixture of marine and freshwater
species. Among marine fishes are cod, herring, hake, plaice, flounder,
shorthorn sculpin, stickleback and turbot, and examples of freshwater
species include perch, pike, whitefish and roach.
There is a decrease in faunal species from the Belts to the Gulf of
Bothnia. The decreasing salinity along this path causes restrictions
in both physiology and habitats. The lack of tides has affected
the marine species as compared with the Atlantic.
Since the Baltic
Sea is so young there are only a few endemic species.
The mostly asexually reproducing brown alga
Fucus radicans seems to
have evolved in the basin. Another endemic is the
parvicardium hauniense. However, several marine species have
populations in the Baltic
Sea adapted to the low salinity, such as the
Sea herring which is smaller than the Atlantic herring.
A peculiar feature of the fauna is that it contains a number of
glacial relict species, isolated populations of arctic species which
have remained in the Baltic
Sea since the last glaciation, such as the
large isopod Saduria entomon, the Baltic subspecies of ringed seal,
and the fourhorn sculpin. Some of these relicts are derived from
glacial lakes, such as Monoporeia affinis, which is a main element in
the benthic fauna of the low-salinity Bothnian Bay.
Cetaceans in Baltic
Sea have been monitored by the ASCOBANS.
Critically endangered populations of Atlantic white-sided dolphins and
harbor porpoises inhabit the sea where white-colored porpoises have
been recorded, and occasionally oceanic and out-of-range species
such as minke whales, bottlenose dolphins, beluga whales,
orcas, and beaked whales visit the waters. In recent years,
very small, but with increasing rates, fin whales and
humpback whales migrate into Baltic sea including mother and calf
pair. Now extinct Atlantic grey whales (remains found from Gräsö
along Bothnian Sea/southern Bothnian Gulf and Ystad) and
eastern population of North Atlantic right whales that is facing
functional extinction once migrated into Baltic Sea.
Strandings of Leatherback turtles have been recorded in Baltic Sea,
too. Other notable megafauna include the basking sharks.
Further information: Baltic
Phytoplankton algal bloom in the Baltic Proper, July 2001
Satellite images taken in July 2010 revealed a massive algal bloom
covering 377,000 square kilometres (146,000 sq mi) in the
Baltic Sea. The area of the bloom extended from
Finland. Researchers of the phenomenon have indicated that algal
blooms have occurred every summer for decades. Fertilizer runoff from
surrounding agricultural land has exacerbated the problem and led to
Approximately 100,000 km2 (38,610 sq mi) of the
Baltic's seafloor (a quarter of its total area) is a variable dead
zone. The more saline (and therefore denser) water remains on the
bottom, isolating it from surface waters and the atmosphere. This
leads to decreased oxygen concentrations within the zone. It is mainly
bacteria that grow in it, digesting organic material and releasing
hydrogen sulfide. Because of this large anaerobic zone, the seafloor
ecology differs from that of the neighbouring Atlantic.
Plans to artificially oxygenate areas of the Baltic that have
experienced eutrophication have been proposed by the University of
Gothenburg and Inocean AB. The proposal intends to use wind-driven
pumps to inject oxygen (air) into waters at, or around, 130m below sea
See also: Baltic
Sea cruiseferries and Ports of the Baltic Sea
Pedestrian pier at Palanga, the most popular sea resort in Lithuania
Construction of the
Great Belt Bridge in
Denmark (completed 1997) and
Øresund Bridge-Tunnel (completed 1999), linking
Sweden, provided a highway and railroad connection between
the Danish mainland (the Jutland Peninsula, precisely the Zealand).
The undersea tunnel of the
Øresund Bridge-Tunnel provides for
navigation of large ships into and out of the Baltic Sea. The Baltic
Sea is the main trade route for export of Russian petroleum. Many of
the countries neighboring the Baltic
Sea have been concerned about
this, since a major oil leak in a seagoing tanker would be disastrous
for the Baltic—given the slow exchange of water. The tourism
industry surrounding the Baltic
Sea is naturally concerned about oil
Much shipbuilding is carried out in the shipyards around the Baltic
Sea. The largest shipyards are at Gdańsk, Gdynia, and Szczecin,
Poland; Kiel, Germany;
Karlskrona and Malmö, Sweden; Rauma, Turku,
and Helsinki, Finland; Riga, Ventspils, and Liepāja, Latvia;
Klaipėda, Lithuania; and Saint Petersburg, Russia.
There are several cargo and passenger ferries that operate on the
Baltic Sea, such as Scandlines, Silja Line, Polferries, the Viking
Line, Tallink, and Superfast Ferries.
Svetlogorsk resort town in
Kaliningrad Oblast, Russia
Mrzeżyno beach in Poland
Ahlbeck (Usedom), Germany
Kamień Pomorski, Poland
For the first time ever, all the sources of pollution around an entire
sea were made subject to a single convention, signed in 1974 by the
then seven Baltic coastal states. The 1974 Convention entered into
force on 3 May 1980.
Helsinki Convention on the Protection of the Marine
Environment of the Baltic
In the light of political changes and developments in international
environmental and maritime law, a new convention was signed in 1992 by
all the states bordering on the Baltic Sea, and the European
Community. After ratification the Convention entered into force on 17
January 2000. The Convention covers the whole of the Baltic
including inland waters and the water of the sea itself, as well as
the seabed. Measures are also taken in the whole catchment area of the
Sea to reduce land-based pollution. The Convention on the
Protection of the Marine Environment of the Baltic
Sea Area, 1992,
entered into force on 17 January 2000.
The governing body of the Convention is the
also known as HELCOM, or Baltic Marine Environment Protection
Commission. The present contracting parties are Denmark, Estonia, the
European Community, Finland, Germany, Latvia, Lithuania, Poland,
Russia and Sweden.
The ratification instruments were deposited by the European Community,
Sweden in 1994, by
Finland in 1995, by
Denmark in 1996, by
Lithuania in 1997 and by
Sea Action Group (BSAG)
Council of the Baltic
Ports of the Baltic Sea
SS Cap Arcona
MS Wilhelm Gustloff
List of cities and towns around the Baltic Sea
List of rivers of the Baltic Sea
^ A healthy serum concentration of sodium is around 0.8–0.85%, and
healthy kidneys can concentrate salt in urine to at least 1.4%.
^ "Coalition Clean Baltic". Archived from the original on 2 June 2013.
Retrieved 5 July 2013.
^ Gunderson, Lance H.; Pritchard, Lowell (1 October 2002). "Resilience
and the Behavior of Large-Scale Systems". Island Press – via Google
^ "Text of
^ "Fragen zum Meer (Antworten) - IOW". www.io-warnemuende.de.
^ Swedish Chemicals Agency (KEMI): The BaltSens Project – The
sensitivity of the Baltic
Sea ecosystems to hazardous compounds[dead
^ Tacitus, Germania(online text): Ergo iam dextro Suebici maris litore
Aestiorum gentes adluuntur, quibus ritus habitusque Sueborum, lingua
Britannicae propior. – "Upon the right of the Suevian
Æstyan nations reside, who use the same customs and attire with the
Suevians; their language more resembles that of Britain." (English
^ Ptolemy, Geography III, chapter 5: "Sarmatia in
Europe is bounded on
the north by the Sarmatian ocean at the Venedic gulf" (online text).
^ (in Swedish) Balteus in Nordisk familjebok.
^ "Indo-European etymology : Query result". 25 February 2007.
Archived from the original on 25 February 2007. CS1 maint: BOT:
original-url status unknown (link)
^ Forbes, Nevill (1910). The Position of the Slavonic Languages at the
present day. Oxford University Press. p. 7.
^ Dini, Pietro Umberto (1997). Le lingue baltiche (in Italian).
Florence: La Nuova Italia. ISBN 978-88-221-2803-4.
^ Cfr. Hartmann Schedel's 1493 (map), where the Baltic
Sea is called
Mare Germanicum, whereas the Northern
Sea is called Oceanus
^ "The History of Russian Amber, Part 1: The Beginning", Leta.st
^ Wend – West Wend. Britannica.com. Retrieved on 23 June 2011.
^ Chemical Weapon Time Bomb Ticks in the Baltic
Sea Deutsche Welle, 1
^ Activities 2006: Overview Archived 14 January 2009 at the Wayback
Sea Environment Proceedings No. 112. Helsinki
^ Sztobryn, Marzenna; Stigge, Hans-Joachim; Wielbińska, Danuta;
Weidig, Bärbel; Stanisławczyk, Ida; Kańska, Alicja; Krzysztofik,
Katarzyna; Kowalska, Beata; Letkiewicz, Beata; Mykita, Monika (2005).
"Sturmfluten in der südlichen Ostsee (Westlicher und mittlerer Teil)"
[Storm floods in the Southern Baltic (western and central part)]
(PDF). Berichte des Bundesamtes für Seeschifffahrt und Hydrographie
(in German) (39): 6. [dead link]
^ "Sturmfluten an der Ostseeküste – eine vergessene Gefahr?" [Storm
floods along the Baltic
Sea coastline – a forgotten threat?].
Informations-, Lern-, und Lehrmodule zu den Themen Küste, Meer und
Integriertes Küstenzonenmanagement. EUCC Die Küsten Union
Deutschland e. V. Retrieved 2 July 2012. Citing Weiss, D.
"Schutz der Ostseeküste von Mecklenburg-Vorpommern". In Kramer, J.;
Rohde, H. Historischer Küstenschutz: Deichbau, Inselschutz und
Binnenentwässerung an Nord- und Ostsee [Historical coastal
protection: construction of dikes, insular protection and inland
drainage at North
Sea and Baltic Sea] (in German). Stuttgart: Wittwer.
^ Tiesel, Reiner (October 2003). "Sturmfluten an der deutschen
Ostseeküste" [Storm floods at the German Baltic
Informations-, Lern-, und Lehrmodule zu den Themen Küste, Meer und
Integriertes Küstenzonenmanagement (in German). EUCC Die Küsten
Union Deutschland e. V. Retrieved 2 July 2012.
Sea - New World Encyclopedia". www.newworldencyclopedia.org.
^ "EuroOcean". Archived from the original on 15 April 2014. Retrieved
14 April 2014.
^ "Geography of the Baltic
Sea Area". Archived from the original on 21
April 2006. Retrieved 27 August 2005. CS1 maint: Unfit url (link)
at envir.ee. (archived) (2006-04-21). Retrieved on 23 June 2011.
^ p. 7
^ "Limits of Oceans and Seas, 3rd edition" (PDF). International
Hydrographic Organization. 1953. Archived from the original (PDF) on 8
October 2011. Retrieved 6 February 2010.
Sea area clickable map". www.baltic.vtt.fi.
^ Helsingin Sanomat, 16 February 2011, p. A8.
^ Derham, William Physico-Theology: Or, A Demonstration of the Being
and Attributes of God from His Works of Creation (London, 1713).
^ Helsingin Sanomat, 10 February 2011, p. A4; 25 February 2011, p. A5;
11 June 2011, p. A12.
Sea Ice Survey Space Science and Engineering Center, University of
^ "Nödåret 1867". Byar i Luleå. Archived from the original on
^ "Isvintrene i 40'erne". TV 2.
^ "1771 - Nationalmuseet".
^ "Is i de danske farvande i 1700-tallet". Nationalmuseet.
^ a b Alhonen, p. 88
^ "The Baltic Sea: Its Past, Present and Future" (PDF). Archived from
the original (PDF) on 6 June 2007. (352 KB), Jan
Thulin and Andris Andrushaitis, Religion, Science and the Environment
Symposium V on the Baltic
^ Statistische Kurzinformation Archived 11 November 2012 at the
Wayback Machine. (in German). Landeshauptstadt Kiel. Amt für
Kommunikation, Standortmarketing und Wirtschaftsfragen Abteilung
Statistik. Retrieved on 11 October 2012.
^ Mikkelson, David. "
UFO at the Bottom of the Baltic Sea? Rumor:
Photograph shows a
UFO discovered at the bottom of the Baltic Sea".
Urban Legends Reference Pages© 1995-2017 by Snopes.com. Snopes.com.
Retrieved 1 August 2017.
^ Kershner, Kate. "What is the Baltic
Sea anomaly?". How Stuff Works.
HowStuffWorks, a division of InfoSpace Holdings LLC. Retrieved 1
^ Wolchover, Natalie. "Mysterious' Baltic
Sea Object Is a Glacial
Deposit". Live Science. Live Science, Purch. Retrieved 1 August
^ Main, Douglas (January 2, 2012). "Underwater UFO? Get Real, Experts
Say". Popular Mechanics.
^ Interview of Finnish planetary geomorphologist Jarmo Korteniemi (at
1:10:45) on Mars Moon Space Tv (2017-01-30), Baltic
Sea Anomaly. The
Unsolved Mystery. Part 1-2, retrieved 2018-03-14
^ Lockwood, A. P. M.; Sheader, M.; Williams, J. A. (1998). "Life in
Salt Marshes, Lagoons and Coastal Waters". In Summerhayes,
C. P.; Thorpe, S. A. Oceanography: An Illustrated Guide (2nd ed.).
London: Manson Publishing. p. 246. ISBN 1-874545-37-5.
^ "White harbour porpoise sighting in Baltic Sea". 10 June 2015.
Minke whale (Balaenoptera acutorostrata) - MarLIN, The Marine Life
^ "Baltic dolphin sightings confirmed".
^ About the beluga - Russian Geographical Society
^ "Orcinus orca (Killer Whale, Orca)". www.iucnredlist.org.
^ "Rare Sowerby's beaked whale spotted in the Baltic Sea".
^ "Wieder Finnwal in der Ostsee". Archived from the original on 15
^ KG, Ostsee-Zeitung GmbH & Co. "Finnwal in der Ostsee gesichtet".
^ Allgemeine, Augsburger. "Angler filmt Wal in Ostsee-Bucht".
^ Jansson N.. 2007. ”Vi såg valen i viken”. Aftonbladet.
Retrieved on September 7, 2017
^ "Whales seen again in the waters of the Baltic Sea".
^ 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
^ Global Biodiversity Information Facility. Occurrence Detail
1322462463. Retrieved on September 21, 2017
^ "North Atlantic right whale".
^ "Regional Species Extinctions - Examples of regional species
extinctions over the last 1000 years and more" (PDF). Archived from
the original (PDF) on 25 April 2011.
^ "Rare Animals Are Mysteriously Turning Up in
Denmark - Mysterious
^ "Satellite spies vast algal bloom in Baltic Sea". BBC News. 23 July
2010. Archived from the original on 26 July 2010. Retrieved 27 July
^ "Oxygenation at a Depth of 120 Meters Could Save the Baltic Sea,
Researchers Demonstrate". Science Daily.
^ Helcom : Welcome Archived 6 May 2007 at the Wayback Machine..
Helcom.fi. Retrieved on 23 June 2011.
This article needs additional citations for verification. Please help
improve this article by adding citations to reliable sources.
Unsourced material may be challenged and removed. (July 2015) (Learn
how and when to remove this template message)
Alhonen, Pentti (1966). "Baltic Sea". In Fairbridge, Rhodes. The
Encyclopedia of Oceanography. New York: Van Nostrand Reinhold Company.
Aarno Voipio (ed., 1981): "The Baltic Sea." Elsevier Oceanography
Series, vol. 30, Elsevier Scientific Publishing, 418 p,
Ojaveer, H.; Jaanus, A.; MacKenzie, B. R.; Martin, G.; Olenin, S.; et
al. (2010). "Status of Biodiversity in the Baltic Sea". PLoS ONE. 5
(9): e12467. doi:10.1371/journal.pone.0012467.
Peter, Bruce (2009). Baltic Ferries. Ramsey, Isle of Man: Ferry
Publications. ISBN 9781906608057.
The BACC II Author Team, , et.al (2015). Second Assessment of Climate
Change for the Baltic
Sea Basin. Springer.
doi:10.1007/978-3-319-16006-1. ISBN 978-3-319-16006-1.
Wikimedia Commons has media related to Baltic Sea.
Wikisource has the text of the 1879
American Cyclopædia article
Wikisource has the text of the 1911 Encyclopædia Britannica article
The Baltic Sea,
Kattegat and Skagerak – sea areas and drainig
basins, poster with integral information by the Swedish Meteorological
and Hydrological Institute
Sea clickable map and details.
Protect the Baltic
Sea while it's still not too late.
Portal – a site maintained by the"Finnish Institute
of Marine Research". Archived from the original on 14 February 2008.
Retrieved 15 July 2007. CS1 maint: Unfit url (link) (FIMR) (in
English, Finnish, Swedish and Estonian)
Encyclopedia of Baltic History
Old shipwrecks in the Baltic
How the Baltic
Sea was changing – Prehistory of the Baltic from the
Polish Geological Institute
Late Weichselian and Holocene shore displacement history of the Baltic
Finland – more prehistory of the Baltic from the Department
of Geography of the University of Helsinki
Baltic Environmental Atlas: Interactive map of the Baltic
Can a New Cleanup Plan Save the Sea? – spiegel.de
List of all ferry lines in the Baltic Sea
Helsinki Commission (HELCOM)
HELCOM is the governing body of the
"Convention on the Protection of the Marine Environment of the Baltic
Baltice.org – information related to winter navigation in the Baltic
Sea Wind – Marine weather forecasts
Ostseeflug – A short film (55'), showing the coastline and the major
German cities at the Baltic sea.
Earth's oceans and seas
East Siberian Sea
Gulf of Boothia
Prince Gustav Adolf Sea
Queen Victoria Sea
Bay of Biscay
Bay of Bothnia
Bay of Campeche
Bay of Fundy
Gulf of Bothnia
Gulf of Finland
Gulf of Lion
Gulf of Guinea
Gulf of Maine
Gulf of Mexico
Gulf of Saint Lawrence
Gulf of Sidra
Gulf of Venezuela
Sea of Åland
Sea of Azov
Sea of Crete
Sea of the Hebrides
Bay of Bengal
Great Australian Bight
Gulf of Aden
Gulf of Aqaba
Gulf of Khambhat
Gulf of Kutch
Gulf of Oman
Gulf of Suez
East China Sea
Gulf of Alaska
Gulf of Anadyr
Gulf of California
Gulf of Carpentaria
Gulf of Fonseca
Gulf of Panama
Gulf of Thailand
Gulf of Tonkin
Mar de Grau
Sea of Japan
Sea of Okhotsk
Seto Inland Sea
South China Sea
King Haakon VII Sea
Countries bordering the Baltic Sea
Inhabited islands in the Baltic Sea
Sea Islands (Åland Islands)
Places on the Baltic coast of Poland
Wolin National Park
Słowiński National Park
Coastal Landscape Park
Bay of Puck
Bay of Gdańsk
Peter the Great
Siege of Leningrad
Gulf of Finland
Society and Culture
World Heritage Site
Heads of Government
Education (primary, secondary, and tertiary)