CESM1.2(CAM5) Pennsylvanian (~300Ma) Simulations by C. Poulsen(UOregon) and S. Macarewich(NCAR)

Figure 2 from Macarewich & Poulsen (2022)

Two Pennsylvanian simulations are performed by Sophia Macarewich and Prof. Chris Poulsen (UOregon). The simulations include the same continental distribution of a late Pennsylvanian (∼300 Ma) paleogeography, deep ocean bathymetry, treatment of aerosols, and solar luminosity. Due to the absence of land over the North Pole in the ∼300 Ma paleogeography, the North Pole of the POP grid is placed over Siberia to avoid a singularity point inside the ocean domain. Deep ocean bathymetry includes an idealized mid-ocean ridge system defined by accretion zones in the Gplates tectonic reconstruction at 300 Ma (www.gplates.org). Mid-ocean ridge crests have a uniform depth of 2,500 m based on the present-day global average. Elsewhere the abyssal seafloor has a uniform depth of 4,000 m and continental shelves at 60-m depth. Aerosol distributions are zonally averaged separately for land and ocean from preindustrial levels. We use a modern Earth orbital configuration, and the total incoming solar irradiance is reduced to a late Pennsylvanian value of 1,333 W m−2 (97.5% of present), following Gough (1981).

The two simulations represent glacial and interglacial intervals of the latest Carboniferous-early Permian and differ with respect to atmospheric pCO2, tropical vegetation, ice sheets, and sea level to represent key differences between interglacial highstand and glacial lowstand conditions. Interglacial and glacial atmospheric CO2 concentrations are 560 and 280 ppm, respectively. In the absence of proxy data, other greenhouse gas concentrations are set to their preindustrial values. The distribution of prescribed vegetation follows the mid-late Pennsylvanian biomes for interglacial and glacial phases, where the closest possible composition of modern plant functional types is chosen to represent each biome. The prescribed land ice geographies for glacial and interglacial simulations are based on reconstructions of paleo-glacier extent and ice stream pathways.

Both simulations are performed with the atmosphere-ocean-land-sea ice coupled CESM1.2(CAM5) with nominal 2-degree latitude/longitude in the atmosphere/land and nominal 1-degree in ocean/sea ice. 

Further details are provided in the papers below:

  • Macarewich, S. I., & Poulsen, C. J. (2022). Glacial-interglacial controls on ocean circulation and temperature during the Permo-Carboniferous. Paleoceanography and Paleoclimatology. https://doi.org/10.1029/2022PA004417
  • Chen, J., Montañez, I.P., Zhang, S., Isson, T.T., Macarewich, S.I., Planavsky, N.J., Zhang, F., Rauzi, S., Daviau, K., Yao, L., Qi, Y., Wang, Y., Poulsen, C.J., Fan, J., Anbar, A., Shen, S. Wang, X. (2022). Marine anoxia linked to abrupt global warming during Earth’s penultimate icehouse. Proceedings of the National Academy of Sciences. https://doi.org/10.1073/pnas.2115231119

We kindly ask that you reference the appropriate paper(s) and acknowledge the Lead Authors, support from UMichigan and computing resources from NSF and NCAR CISL when presenting results based on these simulations in either oral or written form.

Project Details

  • Simulation Names:
    • PV_LPIA4g_B1850C5CN_f19_g16_1xC_WISO.005
    • PV_LPIA4ig_B1850C5CN_f19_g16_2xC_WISO.004d
  • Model Versions: CESM1.2(CAM5)
  • Resolution: f1.9x2.5_gx1v6 (nominal 2o grid atm/lnd, 1o grid ocn/sea ice)
  • Years: 2401-2500 of simulation (final 100 years)
  • Ensemble Size: one
  • Time Frequencies Saved: Monthly [atm/ocn]
  • Machine: NWSC:Cheyenne
  • Compset: B1850C5CN

Data Acquisition

Macarewich, S. I., & Poulsen, C. J. (2022). Glacial-interglacial controls on ocean circulation and temperature during the Permo-Carboniferous. [Dataset]. Zenodo. https://doi.org/10.5281/zenodo.6774491

Diagnostics

None available at this time.