Marquesas Islands - Geography

Geography

The Marquesas Islands group is one of the most remote in the world, lying about 1,371 km (852 mi) northeast of Tahiti and about 4,800 kilometres (3,000 mi) away from the west coast of Mexico, the nearest continental land mass. They fall naturally into two geographical divisions: the northern group, consisting of Eiao, Hatutu (Hatutaa), Motu One, and the islands centered around the large island of Nuku Hiva: Motu Iti (Hatu Iti), Ua Pu, Motu Oa and Ua Huka, and the southern group of Fatu Uku, Tahuata, Moho Tani (Motane), Terihi, Fatu Hiva and Motu Nao (Thomasset Rock), clustered around the main island of Hiva `Oa. With a combined land area of 1,049 square kilometres (405 sq mi), the Marquesas are among the largest island groups of French Polynesia originally discovered by Spanish galleons fleets en route to Manila, Nuku Hiva being the second largest island in the entire territory, after Tahiti. With the exception of Motu One, all the islands of the Marquesas are of volcanic origin.

In contrast to the common perception of lush tropical vegetation that goes culturally hand-in-hand with the appellation "Polynesia", the Marquesas are remarkably dry islands. Although the islands lie within the tropics, they are the first major break in the prevailing easterly winds spawned from the extraordinarily dry (from an atmospheric perspective) Humboldt Current. Because of this, the islands are subject to frequent drought conditions, and only those which reach highest into the clouds (generally, above about 750 m/2,500 ft above sea level) have reliable precipitation. This has led to historical fluctuations in water supply, which have played a crucial role in the sustainability of human populations in certain sections of the various islands throughout the archipelago. This is especially evident in the low historical population of Ua Huka (maximum elevation 857 m/2,812 ft.) and the intermittent inhabitability of Eiao (maximum elevation 576 m/1,890 ft.). The Marquesas Islands are thought to have formed by a center of upwelling magma called the Marquesas hotspot.