Difference between revisions of "Portugal"

Less than one-eighth of Portugal rises above 2,300 feet (700 metres). Most of the country’s mountains are north of the Tagus River, which flows northeast to southwest and divides the country. North of the Tagus, more than nine-tenths of the land rises above 1,300 feet (400 metres); in the south, only one range, São Mamede, surpasses 3,200 feet (1,000 metres).--->[[Relief-Portugal|>>>Read More.<<<]]

Less than one-eighth of Portugal rises above 2,300 feet (700 metres). Most of the country’s mountains are north of the Tagus River, which flows northeast to southwest and divides the country. North of the Tagus, more than nine-tenths of the land rises above 1,300 feet (400 metres); in the south, only one range, São Mamede, surpasses 3,200 feet (1,000 metres).--->[[Relief-Portugal|>>>Read More.<<<]]

All of Portugal’s main rivers flow from Spain over the edge of the Meseta in a series of defiles (narrow gorges), and their usefulness, either for navigation or as routeways for roads and railways, is thus limited. The longest river crossing Portugal, the Douro, which extends some 200 miles (300 km) in the country, has been made navigable from near Porto to the Spanish frontier. In its upper reaches, the Douro riverbed drops 16 feet (5 metres) per mile in gorges 90 to 160 feet (30 to 50 metres) deep, a navigability problem resolved by locks built into five dams, including one that is 115 feet (35 metres) high. The longest river wholly in the country is the 137-mile (220-km) Mondego River, which rises in the Estrela Mountains. Other mainly Portuguese rivers include the Vouga, Sado, and Zêzere (a tributary of the Tagus). Like the Mondego, all are navigable for short distances. Rich silt land (campo) in the lower Tagus valley is the result of regular flooding, which is especially severe when strong southerly gales drive high seas up the estuary. The Guadiana, which flows south into the Gulf of Cádiz, forms part of the frontier with Spain, as does the Minho in the north.

All of Portugal’s main rivers flow from Spain over the edge of the Meseta in a series of defiles (narrow gorges), and their usefulness, either for navigation or as routeways for roads and railways, is thus limited. The longest river crossing Portugal, the Douro, which extends some 200 miles (300 km) in the country, has been made navigable from near Porto to the Spanish frontier. In its upper reaches, the Douro riverbed drops 16 feet (5 metres) per mile in gorges 90 to 160 feet (30 to 50 metres) deep, a navigability problem resolved by locks built into five dams, including one that is 115 feet (35 metres) high. The longest river wholly in the country is the 137-mile (220-km) Mondego River, which rises in the Estrela Mountains. Other mainly Portuguese rivers include the Vouga, Sado, and Zêzere (a tributary of the Tagus). Like the Mondego, all are navigable for short distances. Rich silt land (campo) in the lower Tagus valley is the result of regular flooding, which is especially severe when strong southerly gales drive high seas up the estuary. The Guadiana, which flows south into the Gulf of Cádiz, forms part of the frontier with Spain, as does the Minho in the north.

Portugal has more than 500 miles (800 km) of coastline, four-fifths of which faces westward. Except at the mouths of the larger rivers, there are few major indentations or natural harbours; the most important are those of Lisbon, on the Tagus, and Setúbal, on the Sado. The entrance to the Tagus is a long, narrow deepwater channel opening out into a broad expanse of inland water. Other harbours depend on the protection of headlands (e.g., the artificial harbours of Leixões and Sines).

Portugal has more than 500 miles (800 km) of coastline, four-fifths of which faces westward. Except at the mouths of the larger rivers, there are few major indentations or natural harbours; the most important are those of Lisbon, on the Tagus, and Setúbal, on the Sado. The entrance to the Tagus is a long, narrow deepwater channel opening out into a broad expanse of inland water. Other harbours depend on the protection of headlands (e.g., the artificial harbours of Leixões and Sines).

Most of Portugal’s soils are arid, acidic, and sandy, though in the north the soil often is rocky. Except for parts of northern Portugal that receive significant precipitation and along the country’s primary rivers, which deposit fertile alluvium, the soils are not suitable for intensive agricultural production. In the central and southern parts of the country, the soils are generally poor and incapable of significant agricultural production without extensive irrigation schemes.

Most of Portugal’s soils are arid, acidic, and sandy, though in the north the soil often is rocky. Except for parts of northern Portugal that receive significant precipitation and along the country’s primary rivers, which deposit fertile alluvium, the soils are not suitable for intensive agricultural production. In the central and southern parts of the country, the soils are generally poor and incapable of significant agricultural production without extensive irrigation schemes.

Climate, through its effect on vegetation, divides Portugal. As in Spain, three sets of influences are involved: Atlantic, continental (Mesetan), and Mediterranean. The Atlantic climate predominates overall, putting most of the country into the humid zone of the Iberian Peninsula; this is especially true in the northwest, where the climate is mild and rainy. Summer temperatures near sea level may average up to 76 °F (24 °C) but are rather lower at exposed higher elevations. Winter temperatures average 37 to 40 °F (3 to 4 °C) but tend to be milder south of the Douro. Annual rainfall averages more than 40 inches (1,000 mm).

Climate, through its effect on vegetation, divides Portugal. As in Spain, three sets of influences are involved: Atlantic, continental (Mesetan), and Mediterranean. The Atlantic climate predominates overall, putting most of the country into the humid zone of the Iberian Peninsula; this is especially true in the northwest, where the climate is mild and rainy. Summer temperatures near sea level may average up to 76 °F (24 °C) but are rather lower at exposed higher elevations. Winter temperatures average 37 to 40 °F (3 to 4 °C) but tend to be milder south of the Douro. Annual rainfall averages more than 40 inches (1,000 mm).

Mediterranean, Saharan, and oceanic influences produce seasonal precipitation, occasional dry winds, and thermal equability, respectively, in the Madeiras. Climate varies markedly with altitude. In the Azores the anticyclone dominates, though conditions can be highly variable. Rainfall, for example, is irregular both in annual total and in regime: Horta (on Faial Island) may have more than 40 inches (1,000 mm) a year or may suffer severe drought.

Mediterranean, Saharan, and oceanic influences produce seasonal precipitation, occasional dry winds, and thermal equability, respectively, in the Madeiras. Climate varies markedly with altitude. In the Azores the anticyclone dominates, though conditions can be highly variable. Rainfall, for example, is irregular both in annual total and in regime: Horta (on Faial Island) may have more than 40 inches (1,000 mm) a year or may suffer severe drought.

==Demography of Portugal==

==Demography of Portugal==