The Pacific Islands can be divided into three main groups - Melanesia, Micronesia, and Polynesia. There are two main types of islands: high islands formed from volcanoes with fertile soil, and low islands formed from coral reefs with poor soil. Climate is tropical throughout, with hot temperatures moderated by ocean winds and heavy rainfall. Vegetation varies by island type, from tropical rainforests on high islands to limited vegetation on low islands. Natural resources are few, but tourism leveraging the islands' natural beauty has become an important industry.

1. The Pacific Islands Physical Geography (20.3)

2. Objectives 1. Examine features of high islands and low islands. 2. Learn about the three main island groups. 3. Find out what kind of climate and vegetation the islands have. 4. Discover how land is used in the Pacific Islands.

3. Key Terms 1. High Island 2. Low Island 3. Atoll 4. Coral

4. High Island An island formed from the mountainous top of an ancient volcano.

5. Low Island An island formed from coral reefs or atolls.

6. Atoll A small coral island in the shape of a ring.

7. Coral A rock-like material made up of the skeletons of tiny sea creatures, most plentiful in warm ocean water.

8. The Pacific Islands The thousands of islands in the Pacific Ocean are divided into three groups. Melanesia “Black Islands” Micronesia “Small Islands” Polynesia “Many Islands”

9. The Pacific Islands

10. High Islands High islands are mountainous and have been formed by volcanoes. The soil is very fertile and they can support more people than low islands.

11. Low Islands Low Islands are made up of coral reefs or atolls. Atolls are are small coral islands in the shape of a ring. The ring of an atoll encloses a shallow pool of ocean water called a lagoon.

12. Low Islands Low islands have this shape and low elevation because they are coral reefs. Coral is a rocklike material made up of the skeletons of tiny sea creatures. A reef develops until it nears the surface, then sand and other debris accumulate on the reef’s surface and raises the island above the level of the water. Low islands have poor soil.

13. Melanesia Melanesia is the island group with the most people. Melanesia is north and east of Australia. Most of Melanesia’s islands are high islands.

14. Melanesia

15. Micronesia Micronesia is made up of mostly low islands. Most of Micronesia’s islands are north of the Equator. Micronesia’s islands are divided into several groups: Caroline Gilbert Marshall, and Mariana

16. Micronesia

17. Polynesia Polynesia is the largest island group in the Pacific. Polynesia includes Hawaii. Dense rain forests cover the islands’ high volcanic mountains.

18. Polynesia

19. Climate The Pacific islands lie in the tropics, so temperatures are hot year-round. The ocean winds keep the temperatures from getting too high. Most islands receive heavy rainfall all year long.

20. Vegetation Because of the high temperatures, plentiful rainfall, and fertile soil, high islands have rich vegetation. Tropical rain forests cover the hills and savanna grasses grow in the lowlands. Low islands, have little vegetation because of the poor soil.

21. Vegetation Savanna Tropical Rain Forest

22. Natural Resources The Pacific island region has few natural resources. The coconut palm is the most important resource. Some Pacific islands grow cash crops such as sugar cane and copra. Taro, yams, and sweet potatoes are grown on subsistence farms.

23. Natural Resources Sugar Cane Copra

24. Tourism The Pacific islands’ most valuable resource may be their natural beauty. Tourism provides a key source of income in the region.