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| Titel |
Biospheric response to the Young Toba Tuff super eruption 74ka BP |
| VerfasserIn |
Thomas Kleinen, Davide Zanchettin, Alexander Beitsch, Victor Brovkin, Johann Jungclaus, Stephan Lorenz, Ulrike Niemeier, Claudia Timmreck |
| Konferenz |
EGU General Assembly 2011
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 13 (2011) |
| Datensatznummer |
250048698
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| Zusammenfassung |
| After a volcanic eruption, vegetation responds to the changes in climate induced by the
eruption. In the case of very large eruptions “super-eruptions”, this response is expected to be
very strong. We have investigated the vegetation response to the very large Young Toba Tuff
(YTT) eruption 74 ka BP by forcing the the dynamic global vegetation model LPJ with
climate anomalies derived from a set of experiments with the Max Planck Institute Earth
system model (MPI-ESM).
The YTT eruption is the most recent eruption of a so-called super-eruptions. During this
eruption, an estimated 7x1015 kg of magma was released, along with a stratospheric injection
of sulphur more than one order of magnitude larger than during the 1991 Pinatubo eruption.
The simulated climatic response to YTT eruption is a massive cooling reaching about 3.5K in
global mean temperature, which translates to a summer temperature decrease of more
than 10K over some northern hemisphere (NH) land areas. Simultaneously, annual
precipitation was reduced by more than 1000mm in some equatorial regions, while the
precipitation reduction was in the range of 200-400mm over large continental areas.
The vegetation response to this climate change is a massive dieback of vegetation,
both in tropical rainforests and in NH forests, which are initially replaced by bare
ground. This vegetation change leads to a strong release of carbon stored in the land
biosphere.
A few decades after the eruption, vegetation starts recovering, thereafter going through
ecological succession stages until the pre-eruption state is reached again roughly 180 years
after the eruption. We investigate this vegetation and land carbon cycle response in detail,
imposing the climate anomalies on both a preindustrial climate and a glacial climate state in
order to determine the influence of the climatic background state on the carbon cycle
response. |
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