modelScenario_6

6th Scenario

Information

The 6th scenario starts out from the 2nd scenario. We now wish to vary the resource utilization rate after the year 1970.


References:

  1. Cellier, F.E. (1991), Continuous System Modeling, Springer-Verlag, New York, ISBN: 0-387-97502-0, 755p.
  2. Forrester, J.W. (1971), World Dynamics, Pegasus Communications, 160p.


Simulate the model six times across 200 years while keeping all six trajectories (plot setup menu). For the six simulation runs, choose different levels of resource utilization after the year 1970:
NRUN2 = {0.25, 0.5, 0.75, 1.0, 1.25, 1.5}.

Compute a performance index:
Perf_Index = min_QL + 5*min_dPop;
where min_QL is the minimal quality of life observed between 2000 and 2100, and min_dPop is the largest negative population gradient observed in the same time period.

Plot the performance index across the calendar years between 2000 and 2100 for all six scenarios on a single graph:

NRUN2 = 0.25 and NRUN2 = 0.5 lead to massive die-off, whereas the other scenarios avoid this problem. However in the short run, those scenarios that offer the worst long-term performance are characterized by the best short-term performance. This is the predicament that humanity is currently facing.


Parameters

TypeNameDefaultDescription
RealPopulation_01.65e9World population in 1900
RealPollution_02.0e8Pollution in 1900
RealNat_Resources_09.0e11Unrecoverable natural resources in 1900
RealCap_Invest_04.0e8Capital investment in 1900
RealCIAF_00.2Proportion of capital investment in agriculture in 1900
RealBRN0.04Normal birth rate
RealCIAFN0.3CIAF normalization
RealCIAFT15.0CIAF time constant
RealCIDN0.025Normal capital discard
RealCIGN0.05Normal capital generation
RealDRN0.028Normal death rate
RealECIRN1.0Capital normalization
RealFC1.0Food coefficient
RealFN1.0Food normalization
RealLand_Area1.35e8Area of arable land
RealNRI9.0e11Initial natural resources
RealPOLN1.0Normal pollution
RealPOLS3.5999e9Standard pollution
RealPop_dens_norm26.5Normal population density
RealQLS1.0Standard quality of life
RealNRUN21.0Resource utilization after 1970
RealdPop_fact1Dimensionality factor

Components

TypeNameDefaultDescription
RealPopWorld population
RealPolPollution
RealPol_ratPollution ratio
RealCap_invCapital investment
RealQual_lifeQuality of life
RealNat_resNatural unrecoverable resources
RealNRUNNormal resource utilization
Realrel_dPopRelative derivative of population
Realmin_dPopMinimal derivative of population
Realmin_QLMinimum quality of life
RealPerf_IndexPreformance index
Sources.SourceSource1
Rates.Rate_1Birth_Rate
Levels.LevelPopulation
Rates.Rate_1Death_Rate
Sources.SinkSink1
Sources.SourceSource2
Rates.Rate_1Generation
Levels.LevelNatural_Resources
Rates.Rate_1Depletion
Sources.SinkSink2
Auxiliary.ConstGen_Const
Functions.TabularBRMM
Functions.TabularDRMM
Auxiliary.GainBR_norm
Auxiliary.Prod_5Prod_5_1
Auxiliary.GainDR_norm
Auxiliary.Prod_5Prod_5_2
Functions.TabularBRFM
Functions.TabularBRPM
Functions.TabularBRCM
Functions.TabularDRCM
Functions.TabularDRPM
Functions.TabularDRFM
Auxiliary.GainCrowd_Rat
Auxiliary.Prod_2Prod_2_1
Functions.TabularNRMM
Sources.SourceSource3
Rates.Rate_1CI_Generation
Levels.LevelCapital_Investment
Rates.Rate_1CI_Discard
Sources.SinkSink3
Auxiliary.GainCIG_norm
Auxiliary.Prod_2Prod_2_2
Auxiliary.GainCID_norm
Functions.TabularCIM
Auxiliary.GainMSL
Auxiliary.GainNRFR
Auxiliary.GainECIR
Auxiliary.Prod_3Prod_3_1
Functions.TabularNREM
Modelica.Blocks.Math.DivisionCIR
Sources.SourceSource4
Rates.Rate_1P_Generation
Levels.LevelPollution
Rates.Rate_1P_Absorption
Sources.SinkSink4
Functions.LinearNotCIAF
Auxiliary.GainPol_Ratio
Functions.TabularFCM
Auxiliary.Prod_3Prod_3_2
Auxiliary.GainFood_Ratio
Sources.SourceSource5
Rates.Rate_1CIAFG
Levels.LevelCIAF
Rates.Rate_1CIAFD
Sources.SinkSink5
Auxiliary.GainCIAF_D
Auxiliary.GainCIAF_G
Auxiliary.Prod_2Prod_2_3
Modelica.Blocks.Math.DivisionP_Abs
Auxiliary.GainPol_norm
Auxiliary.Prod_2Prod_2_4
Functions.TabularPOLCM
Functions.TabularPOLAT
Functions.TabularCFIFR
Functions.TabularFPM
Auxiliary.Prod_2Prod_2_5
Auxiliary.GainCIRA
Functions.TabularFPCI
Functions.TabularCIQR
Modelica.Blocks.Math.DivisionQLMF
Functions.TabularQLM
Functions.TabularQLF
Auxiliary.Prod_4Prod_4_1
Functions.TabularQLC
Functions.TabularQLP
Auxiliary.GainQuality_of_Life
Utilities.Parameter_ChangeNR_norm