The implementation of Framework for Improvement by Vertical Enhancement (FIVE) into Energy Exascale Earth System Model (E3SM)

Details

• Journal Title:
  Journal of Advances in Modeling Earth Systems
• Personal Author:
  Lee, Hsiang‐He ; Bogenschutz, Peter ; Yamaguchi, Takanobu
• NOAA Program & Office:
  OAR (Oceanic and Atmospheric Research) ; CSL (Chemical Sciences Laboratory) ; CIRES (Cooperative Institute for Research in Environmental Sciences)
• Description:
  The low cloud bias in global climate models (GCMs) remains an unsolved problem. Coarse vertical resolution in GCMs has been suggested to be a significant cause of low cloud bias because planetary boundary layer parameterizations cannot resolve sharp temperature and moisture gradients often found at the top of subtropical stratocumulus layers. This work aims to ameliorate the low cloud problem by implementing a new computational method, the Framework for Improvement by Vertical Enhancement (FIVE), into the Energy Exascale Earth System Model (E3SM). Three physics schemes representing microphysics, radiation, and turbulence as well as vertical advection are interfaced to vertically enhanced physics (VEP), which allows for these processes to be computed on a higher vertical resolution grid compared to the rest of the E3SM model. We demonstrate the better representation of subtropical boundary layer clouds with FIVE while limiting additional computational cost from the increased number of levels. When the vertical resolution approaches the large eddy simulation-like vertical resolution in VEP, the climatological low cloud amount shows a significant increase of more than 30% in the southeastern Pacific Ocean. Using FIVE to improve the representation of low-level clouds does not come with any negative side effects associated with the simulation of mid- and high-level cloud and precipitation, that can occur when running the full model at higher vertical resolution.
• Keywords:
  Boundary Layer Clouds Boundary Layer Energy Exascale Earth System Model (E3SM)
• Source:
  Journal of Advances in Modeling Earth Systems, 13, e2020MS002240
• DOI:
  https://doi.org/10.1029/2020MS002240
• Document Type:
  Journal Article
• Rights Information:
  CC BY-NC-ND
• Compliance:
  Submitted
• Main Document Checksum:
  urn:sha256:12d00d7cf99e969a6f7a8859333b15bb492e389eb31c12f06ba2c9fc75e6e42f
• Download URL:
  https://repository.library.noaa.gov/view/noaa/40503/noaa_40503_DS1.pdf
• File Type:
  [PDF - 3.80 MB ]