WOLFRAM SYSTEM MODELER
Pollution_DynamicsPollution dynamics |
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Diagram
Wolfram Language
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SystemModel["SystemDynamics.WorldDynamics.World3.Pollution_Dynamics"]
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Information
This model describes the appearance of persistent pollutants. These pollutants are an unwelcome yet inevitable byproduct of our industrial production. Especially air pollution is problematic, because these pollutants are difficult to re-capture, and they remain in the air for a long time, somewhere in the order of 100 years. These then lead to Global Warming.
Whereas the earlier WORLD2 model listed only the appearance and assimilation of pollution itself, the newer WORLD3 model accounts for the possibility of reducing the release of pollutants into the air by improved technology using a second state variable. For example, it may be possible to burn coal in a power plant that captures the released CO2 rather than releasing it into the atmosphere. In this way, the greenhouse gas emissions could be significantly reduced, and thereby, the effects of global warming could be mitigated.
Pollutants can take many forms. For this reason, the WORLD3 model normalizes the pollutants and expresses them in "units of pollution." In accordance with engineering practice, normalized quantities are assumed to be dimensionless (the dimensions are filtered out in the process of normalization), and consequently, pollution in this model is assumed dimensionless. The technology change factor is also dimensionless.
Parameters (17)
| agr_mtl_toxic_index |
Value: 1 Type: Real (1/dollar) Description: Agricultural materials toxicity index |
|---|---|
| assim_half_life_1970 |
Value: 1.5 Type: Real (yr) Description: Pollution assimilation half life in 1970 |
| des_ppoll_index_DPOLX |
Value: 1.2 Type: Real Description: Desired persistent pollution index |
| fr_agr_inp_pers_mtl |
Value: 0.001 Type: Real Description: Effective fraction of agricultural pollution input |
| frac_res_pers_mtl |
Value: 0.02 Type: Real Description: Effective fraction of resource utilization on pollution generation |
| ind_mtl_emiss_fact |
Value: 0.1 Type: Real (1/ton) Description: Industrial materials emission factor |
| ind_mtl_toxic_index |
Value: 10.0 Type: Real Description: Industrial materials toxicity index |
| ind_out_in_1970 |
Value: 790000000000.0 Type: Real (dollar/yr) Description: Industrial output in 1970 |
| p_ppoll_gen_fact_1 |
Value: 1 Type: Real Description: Default persistent pollution generation factor |
| pers_pollution_init |
Value: 25000000.0 Type: Real Description: Initial persistent pollution |
| ppoll_in_1970 |
Value: 136000000.0 Type: Real Description: Persistent pollution in 1970 |
| ppoll_tech_init |
Value: 1 Type: Real Description: Initial persistent pollution technology change factor |
| ppoll_trans_del |
Value: 20 Type: Real (yr) Description: Persistent pollution transmission delay |
| t_air_poll_time |
Value: 4000 Type: Real (yr) Description: Air pollution change time |
| t_policy_year |
Value: 4000 Type: Real (yr) Description: Year of policy change |
| tech_dev_del_TDD |
Value: 20 Type: Real (yr) Description: Technology development time |
| p_ppoll_tech_chg_mlt |
Value: {0, 0, 0, 0} Type: Real[:] Description: Persistent pollution technology change multiplier |
Connectors (10)
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population |
Type: MassInPort Description: Population |
|---|---|---|
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pc_res_use_mlt |
Type: MassInPort Description: Per capita resource utilization |
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arable_land |
Type: MassInPort Description: Arable land |
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agr_inp_per_hect |
Type: MassInPort Description: Agricultural investments per hectare |
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ppoll_tech_mult_icor_COPM |
Type: MassOutPort Description: Technology induced reduction in persistent pollution release |
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ppoll_index |
Type: MassOutPort Description: Persistent pollution index |
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ppoll_gen_rt |
Type: MassOutPort Description: Persistent pollution generation rate |
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industrial_output |
Type: MassInPort Description: Annual industrial output |
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poll_intens_ind |
Type: MassOutPort Description: Persistent pollution intensity index |
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s_yield_mlt_air_poll |
Type: MassOutPort Description: Land yield multiplier to air pollution release |
Components (27)
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Pers_Pollution |
Type: Level Description: p.440 of Dynamics of Growth in a Finite World |
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PPoll_Appear_Rt |
Type: RRate Description: p.435 of Dynamics of Growth in a Finite World |
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PPoll_Assim_Rt |
Type: RRate Description: p.442 of Dynamics of Growth in a Finite World |
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Source1 |
Type: Source Description: This is the (dummy) source model of System Dynamics |
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Sink1 |
Type: Sink Description: This is the (dummy) sink model of System Dynamics |
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PPoll_Appear_Rate |
Type: SMTH3 Description: p.435 of Dynamics of Growth in a Finite World |
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PPoll_Ass_Rt |
Type: PPoll_Assim_Rt Description: p.442 of Dynamics of Growth in a Finite World |
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Assim_Half_Life_Mlt |
Type: Tabular Description: p.453 of Dynamics of Growth in a Finite World |
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PPoll_Index |
Type: Gain Description: p.441 of Dynamics of Growth in a Finite World |
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PPoll_Gen_Rt |
Type: PPoll_Gen_Rt Description: p.428 of Dynamics of Growth in a Finite World |
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PPoll_Gen_Agr |
Type: PPoll_Gen_Agr Description: p.433 of Dynamics of Growth in a Finite World |
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PPoll_Gen_Ind |
Type: PPoll_Gen_Ind Description: p.429 of Dynamics of Growth in a Finite World |
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PPoll_Tech_PTD |
Type: Level1a Description: General System Dynamics level with no outflow |
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PPoll_Tech_Chg_Rt |
Type: Rate_1 Description: Unrestricted rate element with one influencing variable |
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Source2 |
Type: Source Description: This is the (dummy) source model of System Dynamics |
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PPoll_Tech_Ch_Rt |
Type: PPoll_Tech_Chg_Rt Description: Persistent pollution technology change rate |
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P_PPoll_Tech_Chg_mlt_POLGFM |
Type: Tabular Description: Tabular function |
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P_PPoll_Tech_Chg |
Type: P_PPoll_Tech_Chg Description: Percentage of effective pollution technology change |
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P_PPoll_Gen_Fact_2 |
Type: SMTH3 Description: Third-order exponential smoothing |
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S_PPoll_Gen_Fact |
Type: S_PPoll_Gen_Fact Description: p.428 of Dynamics of Growth in a Finite World |
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PPoll_Tech_Mult_Icor_COPM |
Type: Tabular Description: Tabular function |
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Poll_Intens_Ind |
Type: Poll_Intens_Ind Description: Pollution intensity index |
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Gain1 |
Type: Gain Description: Output the product of a gain value with the input signal |
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P_Yield_Mlt_Air_Poll_1 |
Type: Tabular Description: p.310 of Dynamics of Growth in a Finite World |
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P_Yield_Mlt_Air_Poll_2 |
Type: Tabular Description: p.310 of Dynamics of Growth in a Finite World |
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S_Yield_Mlt_Air_Poll |
Type: S_Yield_Mlt_Air_Poll Description: p.310 of Dynamics of Growth in a Finite World |
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Assim_Half_Life |
Type: Gain Description: p.453 of Dynamics of Growth in a Finite World |
Used in Examples (11)
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SystemDynamics.WorldDynamics.World3 Original WORLD3 model |
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SystemDynamics.WorldDynamics.World3 More abundant non-recoverable natural resources |
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SystemDynamics.WorldDynamics.World3 More accessible non-recoverable natural resources and pollution control |
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SystemDynamics.WorldDynamics.World3 More accessible non-recoverable natural resources, pollution control, and land yield enhancement |
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SystemDynamics.WorldDynamics.World3 More accessible non-recoverable natural resources, pollution control, land yield enhancement, and erosion protection |
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SystemDynamics.WorldDynamics.World3 More accessible non-recoverable natural resources, pollution control, land yield enhancement, erosion protection, and resource efficiency |
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SystemDynamics.WorldDynamics.World3 More abundant non-recoverable natural resources and birth control |
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SystemDynamics.WorldDynamics.World3 More abundant non-recoverable natural resources, birth control, and stable industrial output |
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SystemDynamics.WorldDynamics.World3 Combining the measures of Scenarios #6 and #8 |
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SystemDynamics.WorldDynamics.World3 Influencing the future 20 years earlier |
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SystemDynamics.WorldDynamics.World3 Influencing the future 10 years later |