| Model | |||
| T | tt | 60 | Time periods |
| B_ELASMU | alpha | 2 | Elasticity of marginal utility of consumption |
| B_PRSTP | rho | 0.015 | Initial rate of social time preference per year |
| POP0 | L0 | 6514 | 2005 world population millions |
| GPOP0 | gL0 | 0.35 | Growth rate of population per decade |
| POPASYM | popasym | 8600 | Asymptotic population |
| A0 | tfactor0 | 0.02722 | Initial level of total factor productivity |
| GA0 | gA0 | 0.092 | Initial growth rate for technology per decade |
| DELA | deltaA | 0.001 | Decline rate of technol change per decade |
| DK | deltaK | 0.1 | Depreciation rate on capital per year |
| GAMA | eta | 0.3 | Capital elasticity in production function |
| Q0 | -- | 61.1 | 2005 world gross output trill 2005 US dollars |
| K0 | K0 | 137 | 2005 value capital trill 2005 US dollars |
| SIG0 | sigma0 | 0.13418 | CO2-equivalent emissions-GNP ratio 2005 |
| GSIGMA | gsigma0 | -0.073 | Initial growth of sigma per decade |
| DSIG | dsig | 0.003 | Decline rate of decarbonization per decade |
| DSIG2 | dsig2 | 0 | Quadratic term in decarbonization |
| Carbon circulation/Global temperature | |||
| ELAND0 | eland0 | 11 | Carbon emissions from land 2005(GtC per decade) |
| MAT2000 | mat2000 | 808.9 | Concentration in atmosphere 2005 (GtC) |
| MU2000 | mu2000 | 1255 | Concentration in upper strata 2005 (GtC) |
| ML2000 | ml2000 | 18365 | Concentration in lower strata 2005 (GtC) |
| b11 | b11 | Carbon cycle transition matrix Internally given except for b12,b23 |
|
| b12 | b12 | 0.189288 | |
| b21 | b21 | ||
| b22 | b22 | ||
| b23 | b23 | 0.05 | |
| b32 | b32 | ||
| b33 | b33 | ||
| T2XCO2 | t2xco2 | 3 | Equilibrium temp impact of CO2 doubling oC |
| FEX0 | fex0 | -0.06 | Estimate of 2000 forcings of non-CO2 GHG |
| FEX1 | fex1 | 0.3 | Estimate of 2100 forcings of non-CO2 GHG |
| TOCEAN0 | TL0 | 0.0068 | 2000 lower strat. temp change (C) from 1900 |
| TATM0 | T0 | 0.7307 | 2000 atmospheric temp change (C)from 1900 |
| C1 | cr1 | 0.22 | Climate-equation coefficient for upper level |
| C3 | cr3 | 0.3 | Transfer coeffic upper to lower stratum |
| C4 | cr4 | 0.05 | Transfer coeffic for lower level |
| FCO22X | fco22x | 3.8 | Estimated forcings of equilibrium co2 doubling |
| A1 | aa1 | 0 | Damage intercept |
| A2 | aa2 | 0.0028388 | Damage quadratic term |
| A3 | aa3 | 2 | Damage exponent |
| EXPCOST2 | expcost2 | 2.8 | Exponent of control cost function |
| PBACK | pback | 1.17 | Cost of backstop 2005 000$ per tC 2005 |
| BACKRAT | backrat | 2 | Ratio initial to final backstop cost |
| GBACK | gback | 0.05 | Initial cost decline backstop pc per decade |
| LIMMIU | UPMIU[T] | 1 | Upper limit on control rate |
| PARTFRACT1 | partfract1 | 1 | Fraction of emissions under control regime 2005 |
| PARTFRACT2 | partfract2 | 1 | Fraction of emissions under control regime 2015 |
| PARTFRACT21 | partfract21 | 1 | Fraction of emissions under control regime 2205 |
| DPARTFRACT | dpartfract | 0 | Decline rate of participation |
| FOSSLIM | fosslim | 6000 | Maximum cumulative extraction fossil fuels |
| scale1 | scale1 | 194 | Scaling coefficient in the objective function |
| scale2 | scale2 | 381800 | Scaling coefficient in the objective function |
| GRAS original parameters | |||
| modelname | model name | ||
| LOINV | 10 | Lower limit of investment | |
| LOCONS | 20 | Lower limit of consumption | |
| LOEMIT | 0 | Lower limit of CO2 emission | |
| TRANSK | 0.02 | Transversality condition | |
| initmiu | 0.05 | Initial Value of CO2 reduction rate | |
| logutil | 0 | If this value is 1, utility function has logarthsmic form | |
| apco2lim | 0 | if this value is 1, CO2 limitation is applied. | |
| aptmplim | 0 | If this value is 1, temperature limitation is applied. | |
| fixmiu | 1 | Periods for fixing the reduction rate. | |
| Time series parameters | |||
| RMIU[T] | 0.005 | Initial values of reduction rate | |
| UPMIU[T} | 1 | Upper limit of reduction rate | |
| LOMIU[T] | 0.01 | Lower limit of reduction rate | |
| CO2LIM[T] | 596.4X4.0 |
Upper limit of CO2emission | |
| TMPLIM[T] | 20 | Upper limit of temperature increase | |
| Primary optimization parameters | |||
| rmepsi | 1.00E-04 | Main loop convergence | |
| rmiter | 5000 | Main loop max iteration | |
| epsilon | 1.00E-08 | Quasi Newton loop convergence | |
| diffmethod | 0 | Method of Differentiation, 0 by Hand, 1 Numerical | |
| pdiff | 1.00E-07 | Width of partial differentiation | |
| maxiter | 100000 | Max iteration of quasi Newton loop | |
| gamma | 100 | Initial penalty value for constraint | |
| Linear optimization parameters | |||
| maxlsiter | 1000 | Max iteration of linear optimization | |
| penamul | 10 | Multiplier of the above penalty | |
| penabeta | 0.25 | Coefficient for penalty | |
| initmu | 10 | Initial values of lagrange multiplier | |
| lsmethod | 0 | 1:Armijo method, 0:Wolfe method | |
| xi | 0.3 | Inclination judge in Armijo | |
| tau | 0.5 | Multiplier in Armijo | |
| armepsi | 1.00E-08 | Convergence in Armijo | |
| wlfinc | 2 | Multiplier in Wolfe | |
| wlfm1 | 0.3 | Coefficient 1 in Wolfe | |
| wlfm2 | 0.9 | Coefficient 2 in Wolfe | |
| lsepsi | 1.00E-10 | Distance limit in Wolfe | |
| wlftheta | 0.5 | New location coefficient in Wolfe | |