Aqua planet experiment by Neale and Hoskins (2001)

A method to perform an aqua planet experiment (planetary surface is covered by watar) proposed by Neale and Hoskins (2001) is described.

Following physical processes are used in this experiment.

• Radiation (...)
• Vertical diffusion (Mellor and Yamada, 1974, level 2)
• Cumulus parameterization: Convective adjustment scheme (Manabe et al., 1965)
• Large scale condensation
• Dry convective adjustment

1. Overview
2. Preparation of a directory for an experiment
3. Create initial data file
4. Preparation of additional data
5. Create SST data file
6. Run the experiment
7. Visualization of result
8. References

Overview

This experiment requires data of distribution of sea surface temperature. So, the experiment is performed with the following 4 steps:

• Preparation of directory for experiments
• Preparation of initial condition
• Preparation of additional data (sea surface temperature) for experiments
• Execution of experiments

Preparation of a directory for an experiment

Move "practice" directory:

$ cd practice

In the directory, execute 'make' command. The execution files and the NAMELIST files will be automatically copied. Input directory name first of all after inputting 'make' command. (It is assumed "ape-nh01-exp" in the following example). Input 'Enter' to the question after that.

$ make

****** Setup a directory for a experiment ******

  Enter directory name [testXX]: ape-nh01-exp
  Directory in which executable files are prepared
    [../src/main]: 
          :

Move the directory

$ cd ape-nh01-exp

Note that you can perform an experiment in any directory by using executable files and configuration (namelist) files.

Create initial data file

Create initial data file "init_T21L22.nc" using "init_data" and "init_data_ape_nh01_T21L22.nml"

$ ./init_data -N=init_data_ape_nh01_T21L22.nml

 *** MESSAGE [init_data] ***  Run: Initial data generation
 *** MESSAGE [init_data] ***  -- version = $Name: dcpam5-20110615 $$Id: exp-ape-nh01.rd,v 1.6 2011-04-08 03:57:26 yot Exp $
 *** MESSAGE [namelist_util] ***  ----- Initialization Messages -----
 *** MESSAGE [namelist_util] ***    MaxNmlArySize = 256
 *** MESSAGE [namelist_util] ***  -- version = $Name: dcpam5-20110615 $$Id: exp-ape-nh01.rd,v 1.6 2011-04-08 03:57:26 yot Exp $
 *** MESSAGE [timeset] ***  NAMELIST group "timeset_nml" is loaded from "init_data_ape_nh01_T21L22.nml".
                       : 
 *** MESSAGE [initial_data] ***    PsAvr   = 101080.
 *** MESSAGE [initial_data] ***    QVapAvr = 0.
 *** MESSAGE [initial_data] ***    Ueq     = 0.
 *** MESSAGE [initial_data] ***
 *** MESSAGE [initial_data] ***  -- version = $Name: dcpam5-20110615 $$Id: exp-ape-nh01.rd,v 1.6 2011-04-08 03:57:26 yot Exp $
 *** MESSAGE [HistoryClose] ***  "init_T21L22.nc" is closed

 ############## CPU TIME SUMMARY ################
 others                 0.400020E-01
 ------------------------------------------------
        TOTAL TIME =    0.400020E-01

Preparation of additional data

This experiment requires additional data of ozone distribution. Those data are prepared at following site.

• sample data

Please download "O3_NH01_T021.nc" from above site, and place those files at experimental directory.

Create SST data file

Next, create SST data "sst_T21.nc" using "sst_data" and "sst_data_ape_nh01_T21.nml".

$ ./sst_data -N=sst_data_ape_nh01_T21.nml

 *** MESSAGE [sst_data] ***  Run: SST data generation
 *** MESSAGE [sst_data] ***  -- version = $Name: dcpam5-20110615 $$Id: exp-ape-nh01.rd,v 1.6 2011-04-08 03:57:26 yot Exp $
 *** MESSAGE [namelist_util] ***  ----- Initialization Messages -----
 *** MESSAGE [namelist_util] ***    MaxNmlArySize = 256
 *** MESSAGE [namelist_util] ***  -- version = $Name: dcpam5-20110615 $$Id: exp-ape-nh01.rd,v 1.6 2011-04-08 03:57:26 yot Exp $
 *** MESSAGE [timeset] ***  NAMELIST group "timeset_nml" is loaded from "sst_data_ape_nh01_T21.nml".
                       :
 *** MESSAGE [surface_data] ***    SoilHeatCap      = 2100000.
 *** MESSAGE [surface_data] ***    SoilHeatDiffCoef = 1.2
 *** MESSAGE [surface_data] ***  -- version = $Name: dcpam5-20110615 $$Id: exp-ape-nh01.rd,v 1.6 2011-04-08 03:57:26 yot Exp $
 *** MESSAGE [HistoryClose] ***  "sst_T21.nc" is closed

 ############## CPU TIME SUMMARY ################
 others                 0.400000E-02
 ------------------------------------------------
        TOTAL TIME =    0.400000E-02

Run the experiment

At the last, run a experiment using "dcpam_main" and "dcpam_ape_nh01_T21L22.nml". Resolution is T21L22, time step is 20 minutes. Integration time is 7 days. A restart data file, a restart data file of surface data, and some history data files are output.

$ ./dcpam_main -N=dcpam_ape_nh01_T21L22.nml | tee ape-nh01.log

If initial data, surface data, settings of experiments want to be changed, edit "init_data_ape_nh01_T21L22.nml", "sst_data_ape_nh01_T21.nml", "dcpam_ape_nh01_T21L22.nml".

Visualization of result

Zonal mean temperature distribution after integration for 2 days is shown below.

This figure is drawn by using Gphys, as follows:

Please type irb. 

$ irb

Following prompt of irb is shown. 

irb(main):001:0>

Type following lines. Please note that the left-most number is line number, and it has not been typed. 

1: require "numru/ggraph"
2: include NumRu
3: gphys = GPhys::IO.open('Temp.nc', 'Temp')
4: DCL.gropn(1)
5: DCL.sgpset('lcntl', false) ; DCL.uzfact(0.7)
6: GGraph.tone( gphys.mean('lon').cut('time'=>2) )
7: GGraph.color_bar
8: DCL.grcls

Type quit to exit irb. 

Above figure shows spin-up phase of the atmosphere, because the Earth's atmosphere does not reach quasi-equilibrium in 5 days.

References

• Manabe, S., J. Smagorinsky, and R. F. Strickler, 1965: Simulated climatology of a general circulation model with a hydrologic cycle, Mon. Wea. Rev., 93, 769--798.
• Mellor, G. L., and T. Yamada, 1974: A hierarchy of turbulence closure models for planetary boundary layers, J. Atmos. Sci., 31, 1791--1806.
• Neale, R. B., and B. J. Hoskins, 2001: A standard test for AGCMs including their physical parameterizations: I: The proposal, Atmos. Sci. Lett., doi:10.1006/asle.2000.0019.

DCPAM Development Group / GFD Dennou Staff