Although it wasn't realized at the time, the quasi-biennial oscillation (QBO) was observed during the 1883 eruption of Krakatoa, when the ash from the volcano was transported around the globe from east to west by stratospheric winds in about two weeks. These winds became known as the "Krakatoa easterlies". It was observed again in 1908, by the German meteorologist Arthur Berson, who saw that winds blow from the west at altitude in tropical Africa from his balloon experiments. These became known as the "Berson westerlies". However, it was not until the early 1960s that the ~ 26-month cycle of the QBO was first described, independently by Richard J. Reed in 1960 and Veryhard and Ebdon in 1961.