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| Titel |
Modelling the Climate of the Last Interglacial Using a Fully Coupled General Circulation Model |
| VerfasserIn |
Emma Stone, Daniel Lunt |
| 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 |
250051259
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| Zusammenfassung |
| Palaeorecords and previous modelling studies indicate that arctic summers were significantly
warmer during the Last Interglacial (LIG) (~130 to 116ka) and eustatic sea level estimated to
be between approximately 2 to 8 m higher than today, implying less glacial ice on Earth
during this period (e.g. Stirling et al., 1998; Muhs et al., 2002; Kopp et al., 2009). Previous
Atmosphere Ocean General Circulation Model (AOGCM) simulations have shown summer
arctic warming of up to 5Ë C (Montoya et al. 2000; Kaspar et al., 2005) with the largest
warming over Eurasia and in the Greenland region. Since and prior to the last IPCC report,
however, there has been no standardised intercomparison of LIG model simulations from 130
to 125 ka.
Simulations which form part of the Past4Future program (www.past4future.eu/) have
been performed in order to characterise the response of the climate system to changes in
greenhouse gas concentrations and orbital forcings between 130 and 125ka conforming to the
PMIP3 standard. This will enable a standardised intercomparison for the LIG to be realised.
Three snapshots at 130, 128 and 125ka were run using the UK Met Office climate model,
HadCM3 with the MOSES 2.1 land surface scheme, for 500 model years. Comparisons with
proxy records for summer arctic temperatures are made showing general agreement. Changes
in seasonal temperature and hydrology have also been assessed. The greatest change in
near-surface air temperature compared with preindustrial occurs during the summer
months, particularly over Greenland and Eurasia, while winter temperatures in the
Northern Hemisphere are marginally colder than preindustrial. Annual temperatures are
not significantly different compared with preindustrial consistent with the orbital
forcing.
These key climate snapshots will further be used to evaluate low resolution GCM
simulations (e.g. the FAMOUS climate model) which have the ability to perform a transient
simulation between 130 and 125ka without the computational expense required by a more
complex and higher resolution GCM such as HadCM3.
References
Kaspar, F. et al. (2005). A model-data comparison of European temperatures
in the Eemian interglacial. Geophysical Research Letters, 32 (L11703), doi:
10.1029/2005GL022456.
Kopp, R. E. et al. (2009). Probabilistic assessment of sea level during the last interglacial
stage. Nature, 462 (7275), 863-868.
Montoya, M. et al. (2000). Climate simulation for 125 kyr BP with a coupled
ocean-atmosphere general circulation model. Journal of Climate, 13 (6), 1057-1072.
Muhs, D. R. et al. (2002). Timing and warmth of the Last Interglacial period: new
U-series evidence from Hawaii and Bermuda and a new fossil compilation for North
America. Quaternary Science Reviews, 21 (12-13), 1355-1383.
Stirling, C. H. et al. (1998). Timing and duration of the Last Interglacial: evidence for a
restricted interval of widespread coral reef growth. Earth and Planetary Science Letters, 160
(3-4), 745-762. |
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