All of the Hawaiian Islands were formed by volcanoes arising from the sea floor from a magma source described in geological theory as a hotspot. The theory maintains that as the tectonic plate beneath much of the Pacific Ocean moves in a northwesterly direction, the hot spot remains stationary, slowly creating new volcanoes. This explains why only volcanoes on the southern half of the Big Island, and the Loihi Seamount (Lo?ihi) deep below the waters off its southern coast, are presently active, with Loihi being the newest volcano to form.
The last volcanic eruption outside the Big Island happened at Haleakala on Maui in the late 18th century (though recent research suggests that Haleakala's most recent eruptive activity could be hundreds of years older).
The volcanic activity and subsequent erosion created impressive geological features. The Big Island is notable as the world’s fifth highest island.
Because of the islands' volcanic formation, native life before human activity is said to have arrived by the "3 W's": wind (carried through the air), waves (brought by ocean currents), and wings (birds, insects, and whatever they brought with them). The isolation of the Hawaiian Islands in the middle of the Pacific Ocean, and the wide range of environments to be found on high islands located in and near the tropic, has resulted in a vast array of endemic flora and fauna. Hawaii has more endangered species per square mile and has lost a higher percent of its endemic species than anywhere else on Earth.
Areas under the control and protection of the National Park Service include:
Ala Kahakai National Historic Trail on the Big Island
Haleakala National Park in Kula
Hawaii Volcanoes National Park on the Big Island
Kalaupapa National Historical Park in Kalaupapa
Kaloko-Honokohau National Historical Park in Kailua-Kona
Puuhonua O Honaunau National Historical Park in Honaunau (Pu?uhonua o Honaunau)
Pu?ukohola Heiau National Historic Site in Kawaihae (Pu?ukohola Heiau)
USS Arizona Memorial at Honolulu
Climate
The climate of Hawaii is typical for a tropical area, although temperatures and humidity tend to be a bit less extreme than other tropical locales due to the constant trade winds blowing from the east. Summer highs are usually in the upper 80s°F, (around 31°C) during the day and mid 70s, (around 24°C) at night. Winter temperatures during the day are usually in the low to mid 80s, (around 28°C) and (at low elevation) seldom dipping below the mid 60s (18 °C) at night. Snow, although not usually associated with tropics, falls at the higher elevations of Mauna Kea (13,796 feet/ 4,205 meters) and Mauna Loa on the Big Island in some winter months. Snow only rarely falls on Maui’s Haleakala. Mount Waialeale (Wai?ale?ale), on the island of Kauai, is notable for rainfall, as it has the second highest average annual rainfall on Earth, about 460 inches (38 ft. 4 in., or 11.7 m).
Local climates vary considerably on each island, grossly divisible into windward (Ko?olau) and leeward (Kona) areas based upon location relative to the higher mountains. Windward sides face the Northeast Trades and receive much more rainfall; leeward sides are drier and sunnier, with less rain and less cloud cover. This fact is utilized by the tourist industry, which concentrates resorts on sunny leeward coasts.
Hurricanes are a rare occurrence in Hawaii, although it is probable that all the islands of Hawaii have been hit by a hurricane in the past. The worst hurricane to hit Hawaii was Hurricane Iniki in 1992, which showed that Hawaii was indeed vulnerable to a direct hit from a hurricane.