Note:
(a) Iwo Jima
(i) "The Japan Maritime Self-Defense Force (JMSDF) 海上自衛隊 operates a naval air base 硫黄島航空基地 on the island * * * The US Navy's Carrier Air Wing Five, based at the United States Naval Air Facility Atsugi 厚木海軍飛行場 [at 神奈川県] when not embarked/deployed aboard USS George Washington, also uses the base for field carrier landing practice (FCLP)." http://en.wikipedia.org/wiki/Iwo_Jima
(A) Please read section 1 Name.
(B) of course, "Iwo" is the Anglicized form of
iō 硫黄 【いおう】 (n): "sulfur"
(C) The official name of 硫黄島 in Japan, now and before World War II, is "iō-tō," not "iō-jima."
(ii) 硫黄島 (東京都) http://ja.wikipedia.org/wiki/%E7%A1%AB%E9%BB%84%E5%B3%B6_(%E6%9D%B1%E4%BA%AC%E9%83%BD)
(行政区分上は東京都小笠原村に属し、東京都区部からは、南方におよそ1,200km に位置する)
translation: administratively belonging to 東京都小笠原村, about 1,200km south of Tokyo.
translation: Ogasawara mura (village) is made up of [co-extensive with] 小笠原諸島 [硫黄島 is part of it], including the easternmost 南鳥島 and the southernmost 沖ノ鳥島. "The pronunciation, prior to the war was "iō-tō" among island inhabitants and army, and "iō-jima" in part of navy as well as sea charts of Meiji era--the latter was adopted by sea charts of US at the time. After the war, Iwo Jima remained until the administration of the island was reverted to Japan in 1968, when Japan's agency 国土地理院 issued a map which identified the island's pronunciation as "iō-tō."