Aqua planet experiment

A method to perform an aqua planet experiment (planetary surface is covered by watar) is described.

Following physical processes are used in this experiment.

• Radiation (Band model)
  • Longwave radiation (moisture 3 band, dry air 1 band)
  • Shortwave radiation (moisture 1 band)
• 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. Create SST data file
5. Run the experiment
6. Final remark
7. 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

Let us move to the top directory of dcpam5 src tree (assuming dcpam5-YYYYMMDD in the following example). Here, we perform an experiment in ../dcpam5-exp/ape-exp directory. Please create the directory and enter there as follows:

$ mkdir -p ../dcpam5-exp/ape-exp
$ cd ../dcpam5-exp/ape-exp

Then, pleaase create the directories for executable files and configuration files as follows:

$ mkdir bin
$ mkdir conf

Finally, executable files and configuration files are copied as follows:

$ cp ../../dcpam5-YYYYMMDD/src/main/dcpam_main bin
$ cp ../../dcpam5-YYYYMMDD/src/main/init_data  bin
$ cp ../../dcpam5-YYYYMMDD/src/main/sst_data   bin
$ cp ../../dcpam5-YYYYMMDD/exp_setup_files/*.conf conf

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_T21L16.nc" using "init_data" and "init_data_T21L16.conf"

$ ./bin/init_data -N=./conf/init_data_T21L16.nml

                       : 
 *** MESSAGE [restart_file_io] ***  ----- Initialization Messages -----
 *** MESSAGE [restart_file_io] ***  Input::
 *** MESSAGE [restart_file_io] ***    InputFile  =
 *** MESSAGE [restart_file_io] ***  Output::
 *** MESSAGE [restart_file_io] ***    OutputFile = init_T21L16.nc
 *** MESSAGE [restart_file_io] ***    IntTime    = 1. [day]

 *** MESSAGE [HistoryCreate3] ***  "init_T21L16.nc" is created (origin=0. [day])
 *** MESSAGE [initial_data] ***  NAMELIST group "initial_data_nml" is loaded from "./conf/init_data_T21L16.conf".
 *** MESSAGE [initial_data] ***  NAMELIST group "initial_data_nml" is loaded from "./conf/init_data_T21L16.conf".
 *** MESSAGE [initial_data] ***  ----- Initialization Messages -----
 *** MESSAGE [initial_data] ***    Pattern = Small Disturbance of Temperature
 *** MESSAGE [initial_data] ***    TempAvr = 280.
 *** MESSAGE [initial_data] ***    PsAvr   = 100000.
 *** MESSAGE [initial_data] ***    QVapAvr = 0.1E-09

 *** MESSAGE [HistoryClose] ***  "init_T21L16.nc" is closed

Create SST data file

Next, create SST data "sst_T21.nc" using "sst_data" and "sst_data_T21.conf".

$ ./bin/sst_data -N=./conf/sst_data_T21.conf

                       :
 *** MESSAGE [restart_surftemp_io] ***  ----- Initialization Messages -----
 *** MESSAGE [restart_surftemp_io] ***  Input::
 *** MESSAGE [restart_surftemp_io] ***    InputFile  =
 *** MESSAGE [restart_surftemp_io] ***    InputName  = SurfTemp
 *** MESSAGE [restart_surftemp_io] ***  Output::
 *** MESSAGE [restart_surftemp_io] ***    OutputFile = sst_T21.nc
 *** MESSAGE [restart_surftemp_io] ***    IntTime    = 1. [day]

 *** MESSAGE [HistoryCreate3] ***  "sst_T21.nc" is created (origin=0. [day])
 *** MESSAGE [surface_data] ***  NAMELIST group "surface_data_nml" is loaded from "sst_data_T21.nml".
 *** MESSAGE [surface_data] ***  NAMELIST group "surface_data_nml" is loaded from "sst_data_T21.nml".
 *** MESSAGE [surface_data] ***  ----- Initialization Messages -----
 *** MESSAGE [surface_data] ***    Pattern = Hosaka et al. (1998)
 *** MESSAGE [surface_data] ***    SurfTemp     = 302.
 *** MESSAGE [surface_data] ***    Albedo       = 0.15
 *** MESSAGE [surface_data] ***    HumidCoeff   = 1.
 *** MESSAGE [surface_data] ***    RoughLength  = 0.1E-03
 *** MESSAGE [surface_data] ***    HeatCapacity = 0.
 *** MESSAGE [surface_data] ***    TempFlux     = 0.
 *** MESSAGE [surface_data] ***    SurfCond     = 0

 *** MESSAGE [HistoryClose] ***  "sst_T21.nc" is closed

Run the experiment

At the last, run a experiment using "dcpam_main" and "dcpam_ape_T21L16.conf". Resolution is T21L16, 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.

$ ./bin/dcpam_main -N=./conf/dcpam_ape_T21L16.conf | tee ape.log

If initial data, surface data, settings of experiments want to be changed, edit "init_data_T21L16.conf", "sst_data_T21.conf", "dcpam_ape_T21L16.conf".

Final remark

If you would like to keep the results of the numerical experiment, please create a sub directory ("data01" for example), move the files, and keep the current directory neatly.

$ mkdir data01
$ mv *.nc *.log data01/

You can output the results of the numerical experimet concurrently with the execution. Please refer to "Change output settings" in Change experimental setup and try to configure "FilePrefix" variable in NAMELIST "&gtool_historyauto_nml".

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.

DCPAM Development Group / GFD Dennou Staff