 |
| Titel |
Modelling the climate-carbon cycle response to stratospheric volcanic aerosol radiative forcing |
| VerfasserIn |
Aideen Foley, Matteo Willeit, Andrew Friend, Georg Feulner |
| Konferenz |
EGU General Assembly 2013
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 15 (2013) |
| Datensatznummer |
250076346
|
|
|
|
|
|
| Zusammenfassung |
| Large volcanic eruptions can have a significant influence on climate, and can indirectly
influence the global carbon cycle through climate-carbon cycle feedbacks. As such,
major volcanic eruptions offer an opportunity to improve our understanding of
both climate responses to radiative forcing and global carbon cycle responses to
climate. However, the magnitudes of both the climate and carbon cycle responses
to volcanic forcings are difficult to quantify due to the internal variability of the
climate system on interannual timescales, and the low temporal resolution of ice core
CO2 records. Nevertheless, the tremendous opportunity offered by studying such
perturbations and the relevance of the response for future coupled climate-carbon behaviour
motivates us to investigate such events using coupled climate-carbon Earth system
models (ESMs). In this study, three ESMs (SIMEARTH, CLIMBER VECODE,
and CLIMBER LPJ ) are used to simulate the effects of different magnitudes of
volcanic eruption on the coupled global climate-carbon cycle system. Simulated
volcanic events range in magnitude from Volcanic Explosivity Index (VEI) 4 (e.g.
Mount Pelee, 1902) to 8 (e.g. the 1258 ice core event), and include the VEI 6 Mount
Pinatubo eruption in 1991. All models simulate similar levels of cooling in response
to a volcanic event of a given magnitude, but the atmospheric CO2 response is
more variable. For example, a VEI 6 eruption results in a modelled temperature
decrease of 0.3oC to 0.4oC and atmospheric CO2 decrease of 0.1ppm to 3ppm.
Key differences in parameterizations, such as how soil respiration and net primary
productivity respond to temperature and atmospheric CO2, have major impacts on the
modelled dynamics of atmospheric, land, and ocean carbon. The usefulness of
characterising the simulated response of the global carbon cycle to this type of perturbation
with metrics used in previous projects (e.g. C4MIP), such as the sensitivity of the
global carbon cycle to volcanic aerosol-induced cooling (γ) (Friedlingstein et al.,
2006), and the total land carbon response to CO2 (β) (Frank et al., 2010), is also
investigated.
Frank, D.C. et al. (2010), Ensemble reconstruction constraints on the global carbon cycle
sensitivity to climate, Nature, 463(7280), 527–530, doi:10.1038/nature08769.
Friedlingstein, P. et al. (2006), Climate–Carbon Cycle Feedback Analysis: Results
from the C4MIP Model Intercomparison, Journal of Climate, 19(14), 3337–3353,
doi:10.1175/JCLI3800.1. |
|
|
|
|
|
|