modelScenario_2
Information
This is Scenario #2 of the WORLD3 model. In the original scenario, industry stopped growing around 2040 due to an exhaustion of the remaining non-recoverable natural resources.In this modified scenario, the initially available non-recoverable natural resources are doubled to make them last longer. This is a reasonable assumption, as indeed, the projections of available resources have repetitively been raised during recent decades. Consequently, industry is able to grow unabatedly for 20 more years, before the increasing extraction cost finally puts a damper on its further growth. Also postulated in this scenario are advances in resource extraction technology that make it cheaper and more efficient to produce the available resources.
References:
- Meadows, D.H., D.L. Meadows, J. Randers, and W.W. Behrens III (1972), Limits to Growth: A Report for the Club of Rome's Project on the Predicament of Mankind, Universe Books, New York, 205p.
- Meadows, D.L., W.W. Behrens III, D.M., Meadows, R.F. Naill, J. Randers, and E.K.O. Zahn (1974), Dynamics of Growth in a Finite World, Wright-Allen Press, 637p.
- Meadows, D.H., D.L. Meadows, and J. Randers (1992), Beyond the Limits, Chelsea Green, 300p.
- Meadows, D.H., J. Randers, and D.L. Meadows (2004), Limits to Growth: The 30-Year Update, Chelsea Green, 368p.
In order to accomplish this change, you need to modify the initial value of the natural resources as follows:
parameter Real nr_resources_init(unit="ton") = 2e12 "Initial available non-recoverable resources";,
you need to modify the table P_Fr_Cap_Al_Obt_Res_2 that describes the fraction of capital allocated to obtaining resources:
parameter Real p_fr_cap_al_obt_res_2[:] = {1,0.1,0.05,0.05,0.05,0.05,0.05,0.05,0.05,0.05,0.05} "Non-renewable resource fraction remaining";,
and finally, you need to reset one of the switching times in the model:
parameter Real t_fcaor_time(unit="yr") = 2002 "Year of capital allocation to resource use efficiency";.
Simulate the model from 1900 until 2100, and display the same variables as in the book Limits to Growth: The 30-Year Update at page 173:
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Real | agr_mtl_toxic_index | 1 | Agricultural materials toxicity index |
| Real | assim_half_life_1970 | 1.5 | Pollution assimilation half life in 1970 |
| Real | avg_life_land_norm | 1000 | Normal life span of land |
| Real | des_compl_fam_size_norm | 3.8 | Desired normal complete family size |
| Real | des_food_ratio_dfr | 2 | Desired food ratio |
| Real | des_ppoll_index_DPOLX | 1.2 | Desired persistent pollution index |
| Real | des_res_use_rt_DNRUR | 4.8e9 | Desired resource utilization rate |
| Real | food_short_perc_del | 2 | Food shortage perception delay |
| Real | fr_agr_inp_pers_mtl | 0.001 | Effective fraction of agricultural pollution input |
| Real | frac_res_pers_mtl | 0.02 | Effective fraction of resource utilization on pollution generation |
| Real | hlth_serv_impact_del | 20 | Health service impact delay |
| Real | income_expect_avg_time | 3 | Income expected average time |
| Real | ind_mtl_emiss_fact | 0.1 | Industrial materials emission factor |
| Real | ind_mtl_toxic_index | 10.0 | Industrial materials toxicity index |
| Real | ind_out_pc_des | 400 | Desired annual industrial per capita output |
| Real | ind_out_in_1970 | 7.9e11 | Industrial output in 1970 |
| Real | inherent_land_fert | 600 | Inherent land fertility |
| Real | labor_force_partic | 0.75 | Percentage of participating labor force |
| Real | labor_util_fr_del_time | 2 | Labor utilization fraction delay time |
| Real | land_fr_harvested | 0.7 | Land fraction harvested |
| Real | life_expect_norm | 28 | Normal life expectancy |
| Real | lifet_perc_del | 20 | Perceived life-time delay |
| Real | max_tot_fert_norm | 12 | Normal maximal total fertility |
| Real | p_avg_life_agr_inp_1 | 2 | Default average life of agricultural input |
| Real | p_avg_life_agr_inp_2 | 2 | Controlled average life of agricultural input |
| Real | p_avg_life_ind_cap_1 | 14 | Default average life of industrial capital |
| Real | p_avg_life_ind_cap_2 | 14 | Controlled average life of industrial capital |
| Real | p_avg_life_serv_cap_1 | 20 | Default average life of service sector capital |
| Real | p_avg_life_serv_cap_2 | 20 | Controlled average life of service sector capital |
| Real | p_fioa_cons_const_1 | 0.43 | Default fraction of industrial output allocated to consumption |
| Real | p_fioa_cons_const_2 | 0.43 | Controlled fraction of industrial output allocated to consumption |
| Real | p_ind_cap_out_ratio_1 | 3 | Default industrial capital output ratio |
| Real | p_land_yield_fact_1 | 1 | Default land yield factor |
| Real | p_nr_res_use_fact_1 | 1 | Default non-recoverable resource utilization factor |
| Real | p_ppoll_gen_fact_1 | 1 | Default persistent pollution generation factor |
| Real | p_serv_cap_out_ratio_1 | 1.0 | Default fraction of service sector output ratio |
| Real | p_serv_cap_out_ratio_2 | 1.0 | Controlled fraction of service sector output ratio |
| Real | pot_arable_land_tot | 3.2e9 | Total potential arable land |
| Real | ppoll_in_1970 | 1.36e8 | Persistent pollution in 1970 |
| Real | ppoll_trans_del | 20 | Persistent pollution transmission delay |
| Real | processing_loss | 0.1 | Processing loss |
| Real | reproductive_lifetime | 30.0 | Reproductive life time |
| Real | social_adj_del | 20 | Social adjustment delay |
| Real | social_discount | 0.07 | Social discount |
| Real | subsist_food_pc | 230 | Available per capita food |
| Real | tech_dev_del_TDD | 20 | Technology development time |
| Real | urb_ind_land_dev_time | 10 | Urban and industrial land development time |
| Real | t_air_poll_time | 4000 | Air pollution change time |
| Real | t_fcaor_time | 2002 | Year of capital allocation to resource use efficiency |
| Real | t_fert_cont_eff_time | 4000 | Year of continued fertility change |
| Real | t_ind_equil_time | 4000 | Year of industrial equilibrium |
| Real | t_land_life_time | 4000 | Land life time |
| Real | t_policy_year | 4000 | Year of policy change |
| Real | t_pop_equil_time | 4000 | Population equilibrium time |
| Real | t_zero_pop_grow_time | 4000 | Time to zero population growth |
| Real[:] | p_fr_cap_al_obt_res_2 | {1, 0.1, 0.05, 0.05, 0.05, 0.05, 0.05, 0.05, 0.05, 0.05, 0.05} | Non-renewable resource fraction remaining |
| Real[:] | p_ppoll_tech_chg_mlt | {0, 0, 0, 0} | Persistent pollution technology change multiplier |
| Real[:] | p_res_tech_chg_mlt | {0, 0, 0, 0} | Resource technology change multiplier |
| Real[:] | p_yield_tech_chg_mlt | {0, 0, 0, 0} | Yield technology change multiplier |
| Real | agr_inp_init | 5e9 | Initial agricultural input |
| Real | arable_land_init | 0.9e9 | Initial arable land |
| Real | industrial_capital_init | 2.1e11 | Initial industrial investment |
| Real | labor_util_fr_del_init | 1 | Initial delayed labor utilization fraction |
| Real | land_fertility_init | 600 | Initial industrial investment |
| Real | nr_resources_init | 2e12 | Initial available non-recoverable resources |
| Real | perc_food_ratio_init | 1 | Initial perceived food ratio |
| Real | pers_pollution_init | 2.5e7 | Initial persistent pollution |
| Real | pop1_init | 65e7 | Initial population 14 years and younger |
| Real | pop2_init | 70e7 | Initial population 15 to 44 years old |
| Real | pop3_init | 19e7 | Initial population 45 to 64 years old |
| Real | pop4_init | 6e7 | Initial population 65 years and older |
| Real | pot_arable_land_init | 2.3e9 | Initial potential arable land |
| Real | ppoll_tech_init | 1 | Initial persistent pollution technology change factor |
| Real | res_tech_init | 1 | Initial non-recoverable resource technology factor |
| Real | service_capital_init | 1.44e11 | Initial service sector investment |
| Real | urban_ind_land_init | 8.2e6 | Initial urban and industrial land |
| Real | yield_tech_init | 1 | Initial yield technology factor |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Real | population | Total human world population | |
| Real | food | Total annually produced food | |
| Real | industrial_output | Total annual world industrial output | |
| Real | ppoll_index | Persistent pollution index | |
| Real | nr_resources | Remaining non-recoverable natural resources | |
| Real | fioa_ind | Fraction of industrial output allocated to industrial/military complex | |
| Real | s_fioa_agr | Fraction of industrial output allocated to food production | |
| Real | s_fioa_cons | Fraction of industrial output allocated to consumption | |
| Real | s_fioa_serv | Fraction of industrial output allocated to service sector | |
| Real | s_fr_cap_al_obt_res | Fraction of capital allocated to resource use efficiency | |
| Real | life_expectancy | Life expectancy | |
| Real | food_pc | Total annual food per person | |
| Real | serv_out_pc | Total annual services per person | |
| Real | ind_out_pc | Total annual consumer goods per person | |
| Real | human_ecological_footprint | Human ecological footprint | |
| Real | human_welfare_index | Human welfare index | |
| Population_Dynamics | Population_Dynamics1 | Population dynamics | |
| Pollution_Dynamics | Pollution_Dynamics1 | Persistent pollution generation | |
| Arable_Land_Dynamics | Arable_Land_Dynamics1 | Arable land dynamics | |
| Food_Production | Food_Production1 | Food production | |
| Human_Ecological_Footprint | Human_Ecological_Footprint1 | Human ecological footprint | |
| Human_Fertility | Human_Fertility1 | Human fertility | |
| Human_Welfare_Index | Human_Welfare_Index1 | Human welfare index | |
| Industrial_Investment | Industrial_Investment1 | Industrial investment | |
| Labor_Utilization | Labor_Utilization1 | Labor utilization | |
| Land_Fertility | Land_Fertility1 | Land fertility | |
| Life_Expectancy | Life_Expectancy1 | Life expectancy | |
| NR_Resource_Utilization | NR_Resource_Utilization1 | Non-recoverable natural resource utilization | |
| Service_Sector_Investment | Service_Sector_Investment1 | Service sector investment |