Model Information of Potential Use to the IPCC Lead Authors and the AR4
BCC-CM1
20 December, 2005
Beijing Climate Center, National Climate Center, China Meteorological Administration, No.46, S.Road, Zhongguancun Str., Beijing 100081, China
Name of the coupled GCM: BCC-CM1
Name of AGCM: BCC T63
Name of OGCM: IAP T63
Name of sea ice model: thermodynamic
Name of land model: NCC/BATS/Sun snow
2000
Ding, Yihui, Yunqi Ni, Xuehong Zhang, Weijing Li, Min Dong, Zong-Ci Zhao, Zechun Li, Wenhai Shen eds., 2000, Introduction to the short-term climate prediction model system, China Meteorological Press, Beijing, China, 500pp in Chinese;
Climate System Modeling Division (CSMD), 2005, An introduction to The Fist-generation Operational Climate Model at National Climate Center, Advances in Climate System Modeling, 1, 14pp, in both Chinese and English;
Dong, M. ed., 2001, Introduction to National Climate Center Atmospheric general Circulation Model documentation – basic principles and applications, China Meteorological Press, 152pp, in Chinese
Ding, Yihui, Ying Xu, Zong-Ci Zhao, Yong Luo and Xuejie Gao, 2004, Climate change scenarios over east Asia and China in the future 100 years, Climate Change Newsletter 2003/2004, 2-4, in English;
Climate System Modeling Division (CSMD), 2005, An introduction to The Fist-generation Operational Climate Model at National Climate Center, Advances in Climate System Modeling, 1, 14pp, in both Chinese and English;
Coupled GCM: CMIP2, 20C3M
AGCM: EAMIP
1. resolution:
T63 (1.875lon x 1.875lat), L16
2. numerical scheme/grid (advective and time-stepping schemes; model top; vertical coordinate and number of layers above 200 hPa and below 850 hPa)
model top at 25hPa, hybrid P-σ coordinates (E-ta), There are 8 layers above 200hPa and 3 layers below 850hPa. reference-atmospheric scheme, mass-conservation scheme, improved semi-Lagrange method, Morcrette Scheme and k-distributive parameterization scheme, Gregory mass flux scheme, finite difference method, a semi-implicit time-stepping scheme
3. list of prognostic variables (be sure to include, as appropriate, liquid water, chemical species, ice, etc.). Model output variable names are not needed, just a generic descriptive name (e.g., temperature, northward and eastward wind components, etc.)
Temperature, northward and eastward wind components, surface pressure, specific humidity, ice water, liquid water
4. name, terse descriptions, and references (journal articles, web pages) for all major parameterizations. Include, as appropriate, descriptions of:
a. clouds
NEW-ECMWF (Simpson, JAS, 1971, 449-455; Morcrette, JGR, 1991, 96, D5, 9121-9132; Shen et al., 2000; Sang, 2000; Dong and Ping, 2001)
b. Convection
Improved Gregory scheme (Gregory and Rowntree, 1990, MWR, July; Ping et al., 2000)
c. boundary layer
boundary layer (Sang, 2000), snow (Sun and Jin, 2000)
d. SW, LW radiation
NEW/ECMWF1989 (Morcrette, JGR, 1991, 96, D5, 9121-9132; Shen et al., 2000)
e. Any special handling of wind and temperature at top of model
The vertical velocity is set to be zero at top of model.
1. resolution
L30, 1.875oX1.875o
2. numerical scheme/grid, including advection scheme, time-stepping scheme, vertical coordinate, free surface or rigid lid, virtual salt flux or freshwater flux
Uniform longitude-latitude grid without shift poles.
Leap-frog time integration scheme.
Free surface.
Eta vertical coordinate.
Freshwater flux.
3. list of prognostic variables and tracers
Sea surface height, temperature, salinity, horizontal velocity
4. name, terse descriptions, and references (journal articles, web pages) for all parameterizations. Include, as appropriate, descriptions of:
a. eddy parameterization
GM90 scheme from MOM2 (Gent, P.R., McWilliams, J.C., 1990. Isopycnal mixing in ocean circulation models. Journal of Physical Oceanography, 20, 150-155.)
b. bottom boundary layer treatment and/or sill overflow treatment
No
c. mixed-layer treatment
PP scheme within 30S-30N (Pacanowski, R.C., Philander, G., 1981. Parametrization of vertical mixing in numerical models of the tropical ocean. Journal of Physical Oceanography 11, 1442-1451.)
vertical mixing is treated as a constant outside the tropic area.
d. sunlight penetration
MOM2's method described by Rosati, A and K., Miyakoda(1988, J. Phys. Oceanogr., 18, 1601-1626.)
e. tidal mixing
No
f. river mouth mixing
No
g. mixing isolated seas with the ocean
No
h. treatment of North Pole "singularity" (filtering, pole rotation, artificial island?)
Filtering with a artificial island at the polar.
thermodynamic sea ice
1. horizontal resolution, number of layers, number of thickness categories
2. numerical scheme/grid, including advection scheme, time-stepping scheme,
3. list of prognostic variables
4. completeness
5. treatment of salinity in ice
6. brine rejection treatment
7. treatment of the North Pole "singularity" (filtering, pole rotation, artificial island?)
1. resolution (tiling?), number of layers for heat and water
2. treatment of frozen soil and permafrost
3. treatment of surface runoff and river routing scheme
4. treatment of snow cover on land
5. description of water storage model and drainage
6. surface albedo scheme
7. vegetation treatment (canopy?)
8. list of prognostic variables
9. ice sheet characteristics (How are snow cover, ice melting, ice accumulation, ice dynamics handled? How are the heat and water fluxes handled when the ice sheet is melting?)
1. frequency of coupling
One day for oceanic model and one hour for atmospheric, land and sea ice models.
2. Are heat and water conserved by coupling scheme?
No.
3. list of variables passed between components:
a. atmosphere – ocean
b. atmosphere – land
c. land – ocean
d. sea ice – ocean
e. sea ice – atmosphere
a,b,c,d,e
4. Flux adjustment? (heat?, water?, momentum?, annual?, monthly?).
Heat and momentum adjustment
1. If initialized from a control run, which month/year.
2. For control runs, describe spin-up procedure.
A. PDcntrl
B. Firstly, the each component model is integrated with the observed climatologically forcing, e.g. 30 model years for atmospheric model, and 3000 model years for OGCM. Secondly, the coupled model was integrated 50 years from the last year of uncoupled model integration, which can be defined as CGCM spin-up. Finially, the initial condition of the experiment “PDcntr “ is from the last year of the CGCM spin-up integration in the second step.
C. No non-antropogenic aerosols included. Solar constant is 1365 W/M*M.
D. /
A. 20C3M
B. The initial conditions of 20C3M ensemble simulations are from the 1st in March, Jun, Sep, Dec of year 1870 by atmosphere model, respectively.
C./
D. CO2, N2O, CH4, CFC11, CFC12; climatologic mean ozone data from ftp://sprite.llnl.gov/pub/covey/IPCC_4AR_Forcing/
A. SRESA2
B. The initial conditions of SRESA2 ensemble simulations are from the 1st January of year 1880,it is from control experiments, isn’tt from experiment 20C3M.
C./
D. CO2, N2O, CH4, CFC11, CFC12; climatologic mean ozone; data from ftp://sprite.llnl.gov/pub/covey/IPCC_4AR_Forcing/
A. SRESB1
B. The initial conditions of SRESB1 ensemble simulations are from the 1st January of year 1880,it is from control experiments, isn’tt from experiment 20C3M.
D. CO2, N2O, CH4, CFC11, CFC12; climatologic mean ozone ; data from ftp://sprite.llnl.gov/pub/covey/IPCC_4AR_Forcing/
A. 1%to2x
B. The initial conditions of 1%to2x ensemble simulations are from the 1st January of model’year 1980.
C./
D. CO2 increases by 1% per year from 280ppm. The other forcing is same as PDcntr.
A. 1%to4x
B. The initial conditions of 1%to4x ensemble simulations are from the 1%to2x
C./
D. CO2 increases by 1% per year from 560ppm. The other forcing is same as PDcntr.
A. AMIP
B. The initial conditions of AMIP ensemble simulations are from the 1st in March, Jun, Sep, Dec of year 1978 by atmosphere model, respectively.
D. CO2, N2O, CH4, CFC11, CFC12; climatologic mean ozone ; data from ftp://sprite.llnl.gov/pub/covey/IPCC_4AR_Forcing/