February 10, 2014 - The Island of Hawaii
The words of the Hawaii tourism authority which describe the Island of Hawai’i as a “vast canvas of environments” is a fitting caption for this beautifully clear image captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Terra satellite on January 26, 2014.
At 10,432 sq km (4,028 sq mi), the Island of Hawai’i hosts many of the world’s climate zones, for two related reasons: rainfall and altitude. Also known as the “Big Island”, the Island of Hawai’i is home to Mauna Kea, which is the tallest sea mountain in the world at 4,205 m (13,796 ft) and – if measured from seafloor to summit – the tallest mountain on the planet with a distance of more than 9,800 m (32,000 ft). Mauna Kea can be seen as the tan circular region in the northern third of the island.
Despite Mauna Kea’s height, it is Mauna Loa that dominates the Big Island. With an altitude of about 4,169 m (13,678 ft), Mauna Loa is the most massive mountain in the world. It rises south of Mauna Kea, and the dark tans of its slopes dwarf the lighter colored Mauna Kea. Temperatures dip low at the summit of these peaks, resulting in a tree-free polar tundra, which creates the pale brown color of the summit of each mountain.
The tall mountains help shape rainfall patterns, so that desert landscapes exist side-by-side with rainforest. Average yearly rainfall ranges from 204 mm (8 in) to 10,271 mm (404 in). The east side of the island is lush and green with tropical rainforest, as the trade winds which blows from the east-northeast hit the mountains and rise, forming rain clouds. In contrast, much of the northwestern shores of Hawaii, which sit on the lee side of the mountains, are desert. Kona, on the western shore, is green and lush due to the pattern of trade winds which bring rain here. Pale green areas on all sides of the island are agricultural lands and grasslands.
The other environmental force painting Hawaii’s canvas is volcanism. Both Mauna Loa and Mauna Kea are volcanic in origin, although only Mauna Loa has been recently active. The smaller Kilauea, however, is one of the world’s most active volcanoes. Two red hotspots – areas where the thermal sensors on the MODIS instruments detected higher than expected temperatures – mark the summit of Kilauea and the Pu`u `O`o crater. A small plume of steam rises from the summit (the western-most hotspot). The easterly hotspot is larger, as it marks an active lava lake.