Country Guide

The island of New Guinea is three times the size of the United Kingdom and lies to the north of the Australian continent between the equator and 12°S.

The western half of the island is the Indonesian province of Irian Jaya and the eastern half is the Commonwealth state of Papua New Guinea. The island has a single range of high mountains running from east to west with the highest peak rising to 5,000 m/16,400 ft. There is an extensive swampy lowland in the south.

The weather and climate of Papua New Guinea are tropical, similar to that described in greater detail for Indonesia. Because of the great range of altitude, and the different exposures of the north and south coasts to the seasonally alternating north and south monsoons, there are great variations in the amount of rainfall and the time of heaviest fall from place to place.

Temperatures at low altitudes are high throughout the year, with little variation from month to month. The table for Port Moresby, on the south coast, is representative of the temperature and humidity around the year at low levels. Port Moresby, however, with an annual rainfall of 1,125 mm/45 in, is one of the driest places on the island.

Most places have 2,000–3,000 mm/80–120 in of rain a year and in the mountains this may rise as high as 5,000 mm/200 in. The highest mountain in western New Guinea carries a permanent snowfield although it is almost on the equator.

Much of the rain comes in heavy downpours, accompanied by thunder, during afternoon and evening storms; but longer periods of rain occur during the wettest months. The weather in the lowlands is sultry and humid but at higher levels the lower temperature makes for much more pleasant conditions. Much of the island is very inaccessible and some parts are still little known or explored.

The weather and climate of the neighbouring islands of New Britain, New Ireland, and the small islands of the Bismarck Archipelago, between 2° and 6°S, are similar to that of the main island of New Guinea. The climate of islands further east is represented by the table for the port of Kieta, on Bougainville.