Wasaburo Oishi (大石 和三郎, Ōishi Wasaburō, 15 March 1874 – 18 December 1950) was a Japanese meteorologist.

[1] He wrote the first official report from Japan's Aerological Observatory (written in 1926 and in the auxiliary language of Esperanto).

In an attempt to reach an unresponsive foreign audience,[3] Wasaburo Oishi published nineteen reports between 1926 and 1944, all of them written in Esperanto, in total 1246 pages.

[5] Oishi's studies on the jet stream enabled Japan to attack North America during World War II with at least 9,000 incendiary bombs carried by stratospheric balloons and then dropped by a timer mechanism, potentially causing a forest fire.

"Guided by Ooishi's wind charts, 9,000 Fire balloon bombs, called Fu-go, were unleashed by Japan between November 1944 and April 1945."