Abstract
Recent studies on the iron fertilisation of the surface ocean with volcanic ash are
all focused on the immediate time after a volcanic eruption. Here we investigate a
post-eruptive effect: volcanic ash may be re-mobilised into the atmosphere from ash
deposits on land by wind (Langmann, 2013). Therefore it may fertilise the surface
ocean during periods of months to years and not only during a volcanic eruption.
Observations confirm such re-mobilisation events, e.g. after the volcanic eruptions
of Katmai, Alaska (1912), Mt. Hudson, Chile (1991) and Eyjafjallajökull, Iceland
(2010). Even though the Katmai eruption is more than 100 years ago, volcanic ash
re-mobilisation events occur until today. Here we report first model simulation results
after the volcanic eruption of Mt. Hudson, Chile (1991) focusing on the deposition of
volcanic ash into the Atlantic sector of the Antarctic Ocean and its potential to iron-
fertilise surface ocean waters.
