Pernambuco - Physical Geography

Physical Geography

Pernambuco comprises a comparatively narrow coastal zone, a high inland plateau, and an intermediate zone formed by the terraces and slopes between the two.

Its surface is much broken by the remains of the ancient plateau which has been worn down by erosion, leaving escarpments and ranges of flat-topped mountains, called chapadas, capped in places by horizontal layers of sandstone. Ranges of these chapadas form the boundary lines with three states–the Serra dos Irmãos and Serra Vermelha with Piauí, the Serra do Araripe with Ceará, and the Serra dos Cariris Velhos with Paraíba.

The coastal area is fertile, and was formerly covered by the humid Pernambuco coastal forests, the northern extension of the Atlantic Forests (Mata Atlântica) of eastern Brazil. It is now place to extensive sugar cane plantations. It has a hot, humid climate, relieved to some extent by the south-east trade winds.

The middle zone, called the agreste region, has a drier climate and lighter vegetation, including the semi-deciduous Pernambuco interior forests, where many trees lose their leaves in the dry season.

The inland region, called the sertão is high, stony, and dry, and frequently devastated by prolonged droughts (secas). The climate is characterized by hot days and cool nights. There are two clearly defined seasons, a rainy season from March to June, and a dry season for the remaining months. The interior of the state is covered mostly by the dry thorny scrub vegetation called caatinga. The Rio São Francisco is the main water source for this area.

The climate is more mild in the countryside of the state because of the Borborema Plateau ("Planalto da Borborema", popularly known as "Serra das Russas" or "Russians' Mountain"). Some towns are located more than 1000 meters above sea level, and temperatures there can descend to 10 °C (50 °F) and even 5 °C (41 °F) in some cities (i.e., Triunfo) during the winter.

The island of Fernando de Noronha in the Atlantic Ocean, 535 km northeast of Recife, has been part of Pernambuco since 1988.

The rivers of the state include a number of small plateau streams flowing southward to the São Francisco River, and several large streams in the eastern part flowing eastward to the Atlantic. The former are the Moxotó, Ema, Pajeú, Terra Nova, Brigida, Boa Vista and Pontai, and are dry channels the greater part of the year.

The largest of the coastal rivers are the Goiana River, which is formed by the confluence of the Tracunhaem and Capibaribe-mirim, and drains a rich agricultural region in the north-east part of the state; the Capibaribe, which has its source in the Serra de Jacarara and flows eastward to the Atlantic at Recife with a course of nearly 300 miles (480 km); the Ipojuca, which rises in the Serra de Aldeia Velha and reaches the coast south of Recife; the Serinhaen; and the Uná. A large tributary of the Uná, the Rio Jacuhipe, forms part of the boundary line with Alagoas.