Changing the CCSM

1
Changing the CCSM
Paleoclimate Examples
Christine Shields NCAR Paleoclimate Group
shields_at_ucar.edu
2
Atmosphere Examples

• Trace Gases
• atm.setup.csh namelist parameters
• example pre-industrial run
• co2vmr 280.e-06 (355.e-06)
• n20vmr 275.e-09 (311.e-09)
• ch4vmr 750.e-09 (1714.e-09)
• f11vmr 0. (280.e-12)
• f12vmr 0. (503.e-12)
• default values in parenthesis

3
Atmosphere Examples

• Solar Constant/Visible Optical Depth
• atm.setup.csh namelist parameters
• example pre-industrial run
• scon 1.365e6 (1.367e6)
• tauvis 0.035 (0.14)
• default values in parenthesis

4
Coupler Examples

• Orbital Parameters lt 1Ma (million yrs ago)
• cpl.setup.csh namelist parameters
• orb_year unit is AD or BC. BC unit is relative
  to 1950
• Example 11Ka Run
• orb_year -9050
• orb_year 1950 - lt yrs past
• -9050 1950 - 11000
• Example Present Day
• orb_year 1990

5
Coupler Examples

• Orbital Parameters (gt1Ma)
• cpl.setup.csh namelist parameters
• Example 80Ma (late Cretaceous)
• orb_eccen 0. ( 0circular)
• orb_obliq 23.5 (degrees)
• orb_mvelp 0. (degrees longitude)
• Explicitly set obliquity, eccentricity, and
  moving vernal equinox.
• Note orb_year is default and will take
  precedence over explicitly set values

6
Past Orographies

• Changing Orography in the CCSM is currently under
  development. These are the types of things that
  will need to be modified
• Ocean Mask/Grid
• Ice Mask/Grid
• Atmos PHIS/SGH/PS
• Land Sfc types, colors, textures,inland
  water,glacier,leaf/stem area and canopy height
  datasets, runoff dataset
• Cpl all mapping datasets