ACCESS-ESM-PMIP4
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ACCESS-ESM Last Interglacial
The configuration parameters for the Last Interglacial (LIG) should follow the experiment setup in LIG Design.
The configuration for the Last Interglacial Model of ACCESS-ESM is based on the payu version of ACCESS-ESM piControl.
See pre-industrial on how to configure payu.
Differences between piControl and LIG
The differences between piControl and LIG fall in two categories:
Atmospheric
Some concentrations are different between piControl and LIG:
Molecule | pIControl (MMR) | LIG |
CO2 | 4.314801e-04 | 275 ppm |
CH4 | 4.470459e-07 | 695 ppb |
N2O | 4.143596e-07 | 225 pbb |
These values are set in the payu control directory, under Template:Atmosphere/namelists, with the variable names CO2_MMR, CH4MMR, and N2OMMR, respectively. Since ACCESS-ESM expects these values to be in Mass-Mixing Ratio, the desired values have to be converted from ppm/ppb to MMR.
Astronomical
The path of earth around the sun has changed since the last interglacial, so changes have to be accommodated.
Parameter | pIControl | LIG |
eccentricity | 1.6710222E-02 | 0.039378 |
obliquity | 0.409092804 | 24.04° |
perihelion-180° | 102.94719*PI/180.0 | 275.41° |
Date of vernal equinox | March 21 at noon | March 21 at noon |
TAU0 | 2.667 | 170.9046 |