Adriatic Sea

The Adriatic Sea is a beautiful body of water that separates the Italian Peninsula from the Balkan Peninsula. It is the northernmost part of the Mediterranean Sea, stretching from the Strait of Otranto to the Po Valley. This sea touches the coasts of six countries: Albania, Bosnia and Herzegovina, Croatia, Italy, Montenegro, and Slovenia.

The Adriatic Sea is full of interesting features. It has more than 1,300 islands, mostly along its eastern coast. The sea has three basins, with the southern one being the deepest at about 1,233 meters. Its waters are slightly less salty than the rest of the Mediterranean because it receives a lot of fresh water. The sea's temperatures change from warm in summer to cool in winter, helping to create a mild climate for the lands around it.

Many people live along the Adriatic's shores, with big cities such as Bari, Venice, Trieste, and Split. Throughout history, different cultures, including the Etruscan, Illyrian, and Greek, and later the Roman Empire, have lived and ruled here. Today, the Adriatic supports many jobs through fisheries, tourism, and maritime transport, with busy ports like the Port of Trieste and the Port of Split handling lots of cargo and passengers each year.

Name

The name Adriatic Sea comes from an old settlement called Adria. People long ago called the sea Mare Adriaticum or sometimes Mare Superum. Over time, different cultures had their own names for the sea. Today, it is known by many names in the languages of the countries around it, such as Mare Adriatico in Italian and Jadransko more in Serbo-Croatian.

Geography

The Adriatic Sea is a semi-enclosed body of water between the Apennine or Italian Peninsula and the Balkan peninsula. It connects to the Ionian Sea at the Strait of Otranto and stretches about 800 kilometres (500 mi) from northwest to southeast.

The sea contains more than 1,300 islands and islets, most of which lie along the eastern coast, especially in Croatia. These islands vary greatly in size, with some being large enough to support communities. The Adriatic Sea is bordered by several countries, including Italy, Slovenia, Croatia, Bosnia and Herzegovina, Montenegro, and Albania.

The sea's average depth is about 259.5 metres (851 ft), with its deepest point reaching 1,233 metres (4,045 ft). The northern part of the Adriatic is much shallower, rarely exceeding 100 metres (330 ft) in depth.

Coastal currents in the Adriatic are influenced by the shape of the coastline and the inflow of Mediterranean seawater. The Italian coast is relatively smooth, while the opposite shore is rugged and has many islands, leading to more complex water movements.

The Adriatic's surface temperature ranges from about 12°C (54°F) in winter to 30°C (86°F) in summer. In very cold winters, sea ice can form in shallow coastal areas. The sea's salinity levels are slightly higher than the open ocean, ranging between 38 and 39 PSUs.

The climate around the Adriatic varies, with the northern part having humid subtropical conditions and the southern part having a hot-summer Mediterranean climate. Winds such as the bora and sirocco significantly affect weather patterns in the region.

Coastal management

Venice, built on islands near the coast, faces serious risks because the land is sinking. This happens because there is less dirt building up, partly due to dams and people taking sand for building. Even though rules were made to stop using certain water sources, Venice still sometimes floods during high tides called acqua alta.

To protect the city, a big project called MOSE was started. It uses special air-filled barriers that rise up to block extra water from coming in during very high tides. These barriers were first used in October 2020 and help keep water out and protect the buildings. However, using them too often could hurt the water quality in the area.

Geology

The Adriatic Sea and the Po Valley are linked to a moving piece of Earth's crust called a microplate. This microplate, known as the Apulian or Adriatic Plate, separated from a larger plate a very long time ago. Over millions of years, this movement has shaped the land around the Adriatic Sea.

The sea has an active fault line that causes small shifts in the land. Earthquakes have happened in this area for a very long time. The land near the northern part of the Adriatic Sea has also been slowly sinking into the water over the past few thousand years.

The bottom of the Adriatic Sea has many different types of sand and mud. In shallower areas, you can find older sand that was once on a beach. Deeper down, the sea floor is usually muddy. Rivers flowing into the sea bring lots of sand and mud, especially from the northwest side.

The eastern coast of the Adriatic Sea, mainly in Croatia, has many bays and inlets, making it one of the most indented coastlines in the Mediterranean. This shape came from natural processes that wore away the rock over millions of years.

Most of the eastern coast is made of carbonate rocks, but some parts have a special type of rock called flysch. On the western side, especially around the Po Valley, the land has changed a lot over time as the sea level rose and fell. The Venice area is famous for its lagoons, which were formed by rivers bringing sand and mud to the coast.

Biogeography and ecology

The Adriatic Sea has a special mix of water that affects its plants and animals. It brings in some nutrients but also carries away other materials, shaping the life that lives there. This mix helps create different areas within the sea, each with its own kinds of plants and animals.

The Adriatic Sea is full of many different plants and animals, including some that are found only there. There are thousands of species living in its waters. Some parts of the sea have many special plants, like different kinds of sea grasses and algae. The sea is also home to many animals, including dolphins, whales, and large fish like tuna. These animals move through the sea, though fishing has made some groups smaller than before.

Some areas of the Adriatic Sea are protected to help keep these plants and animals safe. Countries around the sea have set aside special places where nature can grow without being disturbed. These protected areas help keep the sea’s rich life healthy for the future.

History

Settlements along the Adriatic Sea date back to between 6100 and 5900 BC in places like Albania and Dalmatia. During ancient times, the eastern coast was home to the Illyrians, while the western coast had peoples from Ancient Italy, such as the Etruscans, before the rise of the Roman Republic. The Greeks also settled along the coast, founding cities like Epidamnos and Apollonia.

The Romans began to influence the region around 246 BC with the creation of a naval base at Brundisium (now Brindisi). This led to conflicts with the Illyrians, ending with the eastern shore becoming part of the Roman Republic. Important ports like Brundisium and Apollonia linked Rome to the East through roads, playing key roles in trade and military movements. Later, cities like Ravenna grew in importance, especially when it became a safe capital for the Western Roman Empire.

Boundaries

Italy and Yugoslavia set the borders of the Adriatic Sea in 1968 and added more rules in 1975. These borders stretch far across the water and include many points linked by straight lines. All the countries that were once part of Yugoslavia agreed to these borders. In the south, the border was not set to avoid problems with Albania’s border, which is still not decided.

Before Yugoslavia broke apart, Albania, Italy, and Yugoslavia agreed on their sea borders. Later, Albania and Italy set their border in 1992. When Croatia joined the European Union, the Adriatic Sea became part of the EU’s inner waters. International rules say the Adriatic is a partly enclosed sea.

Adriatic Euroregion

The Adriatic Euroregion started in 2006 to help countries work together around the Adriatic Sea. It includes many areas from Italy, Slovenia, Croatia, Bosnia–Herzegovina, Montenegro, Albania, and Greece.

Disputes

When Yugoslavia broke apart, the land borders of its parts were not clearly set, making sea borders hard to decide. Albania and Montenegro did not set their sea border until the 1990s.

Croatia and Slovenia tried to set their sea border in the Gulf of Piran in 1992 but could not agree. This caused problems for Croatia joining the EU, but they solved it by agreeing to accept a decision from an international group. However, Croatia still has not fully followed this decision, and the dispute continues.

Bosnia–Herzegovina and Croatia set their sea border in 1999, but a few small areas are still in question. Croatia and Montenegro also have a border issue in the Bay of Kotor, especially around the Prevlaka peninsula. This area was controlled by Yugoslavia’s army and later by United Nations monitors until 2002. Since Montenegro became independent in 2006, this dispute has become less serious.

Economy

Fishing

The Adriatic Sea is important for fishing, with many countries depending on it for their fish supplies. In 2000, the total amount of fish caught was about 110,000 tonnes. Some fish species are caught too often, which is a problem because there are not enough fish left. This happens because of too much fishing, pollution, and changes in the climate.

Italy catches the most fish, with over 465,000 tonnes in 2007. Croatia also catches a lot of fish, mostly sardines and anchovies. Other countries like Albania, Slovenia, and Montenegro also fish in the Adriatic Sea, but catch fewer fish.

Tourism

Countries around the Adriatic Sea are popular places for tourists to visit. Italy, especially around Venice, has many tourists. Croatia is also a big tourist spot, with many places for boats to stop and beautiful beaches. Montenegro and Slovenia also attract visitors.

Tourism is very important for these countries. In Croatia and Montenegro, tourism brings in a lot of money and helps the economy grow.

Transport

There are many big ports along the Adriatic Sea where ships carry cargo and passengers. The biggest cargo ports are in Trieste, Venice, Ravenna, Koper, Rijeka, and Brindisi. The biggest passenger ports are in Split and Ancona.

In 2010, some ports in the Northern Adriatic formed a group to work together and be stronger in Europe’s transportation systems.

Oil and gas

There are projects to find and collect natural gas in the Adriatic Sea. Companies from Italy and Croatia work together to get gas from platforms in the water. There are also searches for oil, but finding it has been difficult. Some oil and gas have been found, but more exploration is happening to find more.