|Coupled model simulations of mid-Holocene ENSO and comparisons with coral oxygen isotope records|
Brown, J.; Collins, M.; Tudhope, A. (2006). Coupled model simulations of mid-Holocene ENSO and comparisons with coral oxygen isotope records. Adv. Geosci. 6: 29-33
In: Advances in Geosciences. Copernicus Publications: Göttingen. ISSN 1680-7340, more
El Nino phenomena; Holocene; Oxygen isotopes; Southern oscillation; Marine
|Authors|| || Top |
- Brown, J.
- Collins, M.
- Tudhope, A.
The sensitivity of El Niño-Southern Oscillation (ENSO) to changes in mean climate is investigated for simulations of pre-industrial and mid-Holocene (6000 years before present) climate using the Hadley Centre coupled atmosphere-ocean model, HadCM3. Orbitally-forced changes in insolation in the mid-Holocene produce changes in seasonality which may alter ENSO amplitude and frequency. The model simulations are compared with mid- Holocene fossil coral oxygen isotope records from the western Pacific Warm Pool. The coral records imply a reduction of around 60% in the amplitude of interannual variability associated with ENSO in the mid-Holocene, while the model simulates a smaller reduction in ENSO amplitude of around 10%. The model also simulates a slight shift to longer period variability and a weakening of ENSO phase-locking to the seasonal cycle in the mid-Holocene. There is little change in the pattern of ENSO tropical precipitation teleconnections in the simulated mid-Holocene climate.