Brazilian jurisdictional waters
Brazilian jurisdictional waters (Portuguese: águas jurisdicionais brasileiras, AJB) are the riverine and oceanic spaces over which Brazil exerts some degree of jurisdiction over activities, persons, installations and natural resources. They comprise internal waters, the territorial sea and exclusive economic zone (EEZ), to a distance of 200 nautical miles (370 kilometres) from baselines along the coast, as well as waters overlying the extended continental shelf, where Brazilian claims of jurisdiction are controversial, as the water column over this stretch of seabed is part of the high seas. The continental shelf of Brazil is under a different legal regime from its overlying waters. The Brazilian Navy covers both the shelf and the waters in its less formal concept of a "Blue Amazon".
The AJB's total claimed area stands at 5,669,852.41 km² (equivalent to 67% of land territory), of which 2,094,656.59 km² are above the extended shelf. These maritime zones are based on the United Nations Convention on the Law of the Sea (UNCLOS). From 1970 until it came into effect in 1994, Brazil had claimed a territorial sea as far as 200 nautical miles from the coast, instead of the present 12, but retains rights over natural resources in this area through its EEZ. Its coastline is the longest in the South Atlantic Ocean, but only three archipelagos contribute to its EEZ: Fernando de Noronha, Trindade and Martin Vaz and Saint Peter and Saint Paul.
Brazil's marine ecosystem is hydrographically and topographically complex and exhibits high rates of endemism and an economic potential in biotechnology. The two prevailing ocean currents, Brazil and North Brazil, have warm, nutrient-poor waters sustaining relatively low biomasses for each species, with a correspondingly limited fishing potential. In winter, cold waters of the Falkland Current may reach as far as the 24th parallel south and cold fronts and extratropical cyclones bring rough seas. The wind, waves, tides and thermal and osmotic gradients offer untouched potentials for renewable energy generation. 26.4% of the EEZ was under protected areas in 2021, mostly around the remote archipelagos of Saint Peter and Saint Paul and Trindade and Martin Vaz. Both are only populated by researchers and military personnel, which is one of the reasons for the government's marine science programs.
Most of the country's population lives near the coast and most of its international trade is conducted through the sea, but local shipbuilding and the national merchant marine have little presence in this trade. Coastal shipping answers a modest share of internal trade and mostly covers the oil and natural gas sector. There is no official measurement of the Brazilian maritime economy; 2015 estimates placed it at 2.67% of the gross domestic product directly tied to the sea, mostly in the tourism-dominated service sector. Coast guard duties in jurisdictional waters are assigned to the Navy.