Source code documentation

clip(returnifgte, returniflt, inputvalue, threshold)

Returns returnifgte if the value inputvalue is greater than the threshold threshold, returniflt otherwise. This function corresponds to the CLIP (also called FIFGE) function in the DYNAMO language.

interpolate(x, yvalues, xrange)

Returns the value of a function with input x, by linearly interpolating the function itself through the table yvalues and the range xrange. If x is out of the range, the value at the corresponding extremity is returned. This function corresponds to the TABHL function in the DYNAMO language. This latter function receives a table (that is, yvalues), a value (that is, x), a left and a right extreme of an interval (that is, xrange), and an increment value.

step(inputvalue, returnifgte, threshold)

Returns 0 if the value inputvalue is smaller than the threshold threshold, returnifgte otherwise. This function corresponds to the STEP function in the DYNAMO language.

switch(returnifzero, returnifnotzero, inputvalue)

Returns returnifzero if the value inputvalue is approximately 0 with tolerance 1e-16, returnifnotzero otherwise. This function corresponds to the SWITCH (also called FIFZE) function in the DYNAMO language.

plotvariables(solution, xrange, variables::Vector{<:NTuple{4, Any}}; title="", showaxis=true, showlegend=true, linetype="lines", colored=true)

Plot the values of the variables in the vector variables obtained by the ODE system solution (normally, obtained by using the solve function in solvesystems.jl) in the specified xrange interval. For each variable, the vector variables includes a quadruple, containing the Julia variable, its range, and its symbolic name to be shown in the plot.

compose(systems::Vector{ODESystem}, connection_eqs::Vector{Equation})

Return the ODE system obtained by composing the ODE systems in the vector systems and by making use of the variable equalities in connection_eqs. Normally, each ODE systems in systems corresponds to a subsystem of a system in the World3 model, and the variable equalities specify which variables are shared between the subsystems.

solve(system::ODESystem, timespan; solver=AutoVern9(Rodas5())

Return the solution of the system ODE system in the timespan interval (for the available different ODE system solvers, see the documentation of DifferentialEquations.jl).

We use the AutoVern9(Rodas5()) solver since it is among the suggested ones in the documentation of DifferentialEquations.jl, and among those we tested, it is the one that works best.

variable_connections(systems::Vector{ODESystem}) Return the set of variable equalities establishing the connections between the variables in the ODE systems included in the vector systems. The function assumes that no two distinct variables have the same name (even if they are defined in different ODE systems).

fig_1(; kwargs...)

Reproduce Fig. W1-7/5-1. The original figure is presented in the MIT memorandum D-1348 of World1.

fig_10(; kwargs...)

Reproduce Fig. W1-7/5-10. The original figure is presented in the MIT memorandum D-1348 of World1.

fig_11(; kwargs...)

Reproduce Fig. W1-7/5-11. The original figure is presented in the MIT memorandum D-1348 of World1.

fig_12(; kwargs...)

Reproduce Fig. W1-7/5-12. The original figure is presented in the MIT memorandum D-1348 of World1.

fig_2(; kwargs...)

Reproduce Fig. W1-7/5-2. The original figure is presented in the MIT memorandum D-1348 of World1.

fig_3(; kwargs...)

Reproduce Fig. W1-7/5-3. The original figure is presented in the MIT memorandum D-1348 of World1.

fig_4(; kwargs...)

Reproduce Fig. W1-7/5-4. The original figure is presented in the MIT memorandum D-1348 of World1.

fig_5(; kwargs...)

Reproduce Fig. W1-7/5-5. The original figure is presented in the MIT memorandum D-1348 of [World1](https://dome.mit.edu/handle/1721.3/189645).

fig_6(; kwargs...)

Reproduce Fig. W1-7/5-6. The original figure is presented in the MIT memorandum D-1348 of World1.

fig_7(; kwargs...)

Reproduce Fig. W1-7/5-7. The original figure is presented in the MIT memorandum D-1348 of World1.

fig_8(; kwargs...)

Reproduce Fig. W1-7/5-8. The original figure is presented in the MIT memorandum D-1348 of World1.

fig_9(; kwargs...)

Reproduce Fig. W1-7/5-9. The original figure is presented in the MIT memorandum D-1348 of World1.

fig_std(; kwargs...)

Reproduce Fig. WORLD1-STD. The original figure is presented in the MIT memorandum D-1348 of World1.

fig_4_1(; kwargs...)

Reproduce Fig. 4-1. The original figure is presented in Chapter 4 of WD.

Caption: Basic behavior of the world model, showing the mode in which industrialization and population are suppressed by falling natural resources.

fig_4_10(; kwargs...)

Reproduce Fig. 4-10. The original figure is presented in Chapter 4 of WD.

Caption: System ratios when growth is suppressed by crowding.

fig_4_11(; kwargs...)

Reproduce Fig. 4-11. The original figure is presented in Chapter 4 of WD.

Caption: Food shortage as the only remaining pressure to stop population growth.

fig_4_12(; kwargs...)

Reproduce Fig. 4-12. The original figure is presented in Chapter 4 of WD.

Caption: System ratios during the food-shortage mode.

fig_4_2(; kwargs...)

Reproduce Fig. 4-2. The original figure is presented in Chapter 4 of WD.

Caption: Original model as in Fig. 4-1. Material standard of living reaches a maximum and then declines as natural resources are depleted.

fig_4_3(; kwargs...)

Reproduce Fig. 4-3. The original figure is presented in Chapter 4 of WD.

Caption: Original model as in Fig 4-1. Natural-resource-usage rate reaches a peak about year 2010 and declines as natural resources, population, and capital investment decline.

fig_4_4(; kwargs...)

Reproduce Fig. 4-4. The original figure is presented in Chapter 4 of WD.

Caption:Original model as in Fig. 4-1. The rate of capital-investment generation declines after 2010 but does not fall below the rate of capital-investment discard until 2040, at which time the level of capital investment begins to decline.

fig_4_5(; kwargs...)

Reproduce Fig. 4-5. The original figure is presented in Chapter 4 of WD.

Caption: Reduced usage rate of natural resources leads to a pollution crisis.

fig_4_6(; kwargs...)

Reproduce Fig. 4-6. The original figure is presented in Chapter 4 of WD.

Caption: System ratios during the pollution mode of growth suppression.

fig_4_7(; kwargs...)

Reproduce Fig. 4-7. The original figure is presented in Chapter 4 of WD.

Caption: Dynamics of the pollution sector. A positive-feedback growth in pollution occurs when the pollution-absorption time increases faster than the pollution.

fig_4_8(; kwargs...)

Reproduce Fig. 4-8. The original figure is presented in Chapter 4 of WD.

Caption: Population sector during the pollution mode.

fig_4_9(; kwargs...)

Reproduce Fig. 4-9. The original figure is presented in Chapter 4 of WD.

Caption: Growth suppressed by crowding when natural resources and pollution are inactive.

fig_5_1(; kwargs...)

Reproduce Fig. 5-1. The original figure is presented in Chapter 5 of WD.

Caption: Higher capital-investment generation triggers the pollution crisis.

fig_5_10(; kwargs...)

Reproduce Fig. 5-10. The original figure is presented in Chapter 5 of WD.

Caption: Ratios for the conditions of Fig. 5-9. Higher food productivity causes capital reallocation away from agriculture.

fig_5_11(; kwargs...)

Reproduce Fig. 5-11. The original figure is presented in Chapter 5 of WD.

Caption: Increased food production causes greater population and earlier pollution crisis compared with Fig. 5-8.

fig_5_12(; kwargs...)

Reproduce Fig. 5-12. The original figure is presented in Chapter 5 of WD.

Caption: Compared with Fig. 5-11, increased capital generation causes an earlier pollution crisis.

fig_5_13(; kwargs...)

Reproduce Fig. 5-13. The original figure is presented in Chapter 5 of WD.

Caption: Compared with Fig. 5-12, less pollution generation increases peak population and delays the pollution crisis.

fig_5_14(; kwargs...)

Reproduce Fig. 5-14. The original figure is presented in Chapter 5 of WD.

Caption: Compared with Fig. 5-12, reduced birth rate lowers the peak population but does not ellminate or delay the pollution crisis.

fig_5_2(; kwargs...)

Reproduce Fig. 5-2. The original figure is presented in Chapter 5 of WD.

Caption: Lower birth rate does not affect suppression of growth by falling natural resources.

fig_5_3(; kwargs...)

Reproduce Fig. 5-3. The original figure is presented in Chapter 5 of WD.

Caption: Ratios for the same condition of lower birth rate as in Fig. 5-2.

fig_5_4(; kwargs...)

Reproduce Fig. 5-4. The original figure is presented in Chapter 5 of WD.

Caption: Reduced birth rate still leads to the pollution crisis.

fig_5_5(; kwargs...)

Reproduce Fig. 5-5. The original figure is presented in Chapter 5 of WD.

Caption: With resource depletion and pollution suppressed, population still climbs even with a 30% reduction in "normal" birth rate.

fig_5_6(; kwargs...)

Reproduce Fig. 5-6. The original figure is presented in Chapter 5 of WD.

Caption: A 50% reduction in "normal" birth rate causes growth of population to pause for 20 years, then resume.

fig_5_7(; kwargs...)

Reproduce Fig. 5-7. The original figure is presented in Chapter 5 of WD.

Caption: Ratios for conditions of Fig. 5-6.

fig_5_8(; kwargs...)

Reproduce Fig. 5-8. The original figure is presented in Chapter 5 of WD.

Caption: Reduction of pollution generation allows population and capital investment to increase further before the pollution crisis.

fig_5_9(; kwargs...)

Reproduce Fig. 5-9. The original figure is presented in Chapter 5 of WD.

Caption: Increased food production causes increased population.

fig_6_1(; kwargs...)

Reproduce Fig. 6-1. The original figure is presented in Chapter 6 of WD.

Caption: Natural-resource-usage rate and pollution generation are reduced in 1970.

fig_6_2(; kwargs...)

Reproduce Fig. 6-2. The original figure is presented in Chapter 6 of WD.

Caption: Ratios for conditions of Fig. 6-1.

fig_6_3(; kwargs...)

Reproduce Fig. 6-3. The original figure is presented in Chapter 6 of WD.

Caption: Capital generation is reduced 40% in 1970 in addition to changes in Fig. 6-1. Population stabilizes at a lower level; quality of life is increased.

fig_6_4(; kwargs...)

Reproduce Fig. 6-4. The original figure is presented in Chapter 6 of WD.

Caption: Ratios for conditions of Fig. 6-3.

fig_6_5(; kwargs...)

Reproduce Fig. 6-5. The original figure is presented in Chapter 6 of WD.

Caption: Food productivity is reduced 20% in 1970 along with changes in Fig. 6-3. Population is lower, quality of life higher.

fig_6_6(; kwargs...)

Reproduce Fig. 6-6. The original figure is presented in Chapter 6 of WD.

Caption: Ratios for conditions of Fig. 6-5.

fig_6_7(; kwargs...)

Reproduce Fig. 6-7. The original figure is presented in Chapter 6 of WD.

Caption: Normal birth rate reduced 30% in 1970 along with changes in Fig. 6-5. Population is lower, quality of life higher again.

fig_6_8(; kwargs...)

Reproduce Fig. 6-8. The original figure is presented in Chapter 6 of WD.

Caption: Ratios for conditions of Fig. 6-7.

fig_69a(; kwargs...)

Reproduce Fig 4.69a. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-1: historical run. The behavior of land yields and food production.

fig_69b(; kwargs...)

Reproduce Fig 4.69b. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-1: historical run. The behavior of arable land.

fig_69c(; kwargs...)

Reproduce Fig 4.69c. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-1: historical run. The allocation mechanism.

fig_69d(; kwargs...)

Reproduce Fig 4.69d. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-1: historical run. The behavior of land fertility.

fig_70a(; kwargs...)

Reproduce Fig 4.70a. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-2: standard run. The behavior of land yields and food production.

fig_70b(; kwargs...)

Reproduce Fig 4.70b. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-2: standard run. The behavior of arable land.

fig_70c(; kwargs...)

Reproduce Fig 4.70c. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-2: standard run. The allocation mechanism.

fig_70d(; kwargs...)

Reproduce Fig 4.70d. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-2: standard run. The behavior of land fertility.

fig_72a(; kwargs...)

Reproduce Fig 4.72a. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-3: sensitivity test of the land yield multiplier from capital table, using the optimistic LYMCT. The behavior of land yields and food production.

fig_72b(; kwargs...)

Reproduce Fig 4.72b. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-3: sensitivity test of the land yield multiplier from capital table, using the optimistic LYMCT. The behavior of arable land.

fig_73a(; kwargs...)

Reproduce Fig 4.73a. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-4: sensitivity test of the land yield multiplier from capital table, using the pessimistic LYMCT. The behavior of land yields and food production.

fig_73b(; kwargs...)

Reproduce Fig 4.73b. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-4: sensitivity test of the land yield multiplier from capital table, using the pessimistic LYMCT. The behavior of arable land.

fig_74a(; kwargs...)

Reproduce Fig 4.74a. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-5: sensitivity test with a 35 percent increase in the estimate of the value of potentially arable land total. The behavior of land yields and food production.

fig_74b(; kwargs...)

Reproduce Fig 4.74b. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-5: sensitivity test with a 35 percent increase in the estimate of the value of potentially arable land total. The behavior of arable land.

fig_75a(; kwargs...)

Reproduce Fig 4.75a. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-6: sensitivity test with a 25 percent decrease in the estimate of the value of potentially arable land total. The behavior of land yields and food production.

fig_75b(; kwargs...)

Reproduce Fig 4.75b. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-6: sensitivity test with a 25 percent decrease in the estimate of the value of potentially arable land total. The behavior of arable land.

fig_76a(; kwargs...)

Reproduce Fig 4.76a. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-7: sensitivity test with a 35 percent increase in the estimate of the value of potentially arable land total and development costs adjusted to maintain historical behavior. The behavior of land yields and food production.

fig_76b(; kwargs...)

Reproduce Fig 4.76b. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-7: sensitivity test with a 35 percent increase in the estimate of the value of potentially arable land total and development costs adjusted to maintain historical behavior. The behavior of arable land.

fig_77a(; kwargs...)

Reproduce Fig 4.77a. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-8: sensitivity test with a 35 percent increase in the estimate of the value of potentially arable land total and a 50 percent increase in the upper limit of the land yield multiplier from capital. The behavior of land yields and food production.

fig_77b(; kwargs...)

Reproduce Fig 4.77b. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-8: sensitivity test with a 35 percent increase in the estimate of the value of potentially arable land total and a 50 percent increase in the upper limit of the land yield multiplier from capital. The behavior of arable land.

fig_78a(; kwargs...)

Reproduce Fig 4.78a. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-9: sensitivity test with a 25 percent decrease in the estimate of the value of potentially arable land total and a 25 percent decrease in the upper limit of the land yield multiplier from capital. The behavior of land yields and food production.

fig_78b(; kwargs...)

Reproduce Fig 4.78b. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-9: sensitivity test with a 25 percent decrease in the estimate of the value of potentially arable land total and a 25 percent decrease in the upper limit of the land yield multiplier from capital. The behavior of arable land.

fig_82a(; kwargs...)

Reproduce Fig 4.82a. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-10: sensitivity test with optimistic estimates of the cost of land development, the adverse effects of air pollution on yield, and the extent to which high land yield causes land erosion. The behavior of land yields and food production.

fig_82b(; kwargs...)

Reproduce Fig 4.82b. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-10: sensitivity test with optimistic estimates of the cost of land development, the adverse effects of air pollution on yield, and the extent to which high land yield causes land erosion. The behavior of arable land.

fig_83a(; kwargs...)

Reproduce Fig 4.83a. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-11: sensitivity test with pessimistic estimates of the cost of land development, the adverse effects of air pollution on yield, and the extent to which high land yield causes land erosion. The behavior of land yields and food production.

fig_83b(; kwargs...)

Reproduce Fig 4.83b. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-11: sensitivity test with pessimistic estimates of the cost of land development, the adverse effects of air pollution on yield, and the extent to which high land yield causes land erosion. The behavior of arable land.

fig_84a(; kwargs...)

Reproduce Fig 4.84a. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-12: policy run in which the impairment of land fertility from persistent pollutants is completely eliminated in 1975. The behavior of land yields and food production.

fig_84b(; kwargs...)

Reproduce Fig 4.84b. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-12: policy run in which the impairment of land fertility from persistent pollutants is completely eliminated in 1975. The behavior of arable land.

fig_85a(; kwargs...)

Reproduce Fig 4.85a. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-13: policy run in which the adverse effects of air pollution on land yield and the impairment of land fertility by persistent pollutants are completely eliminated in 1975. The behavior of land yields and food production.

fig_85b(; kwargs...)

Reproduce Fig 4.85b. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-13: policy run in which the adverse effects of air pollution on land yield and the impairment of land fertility by persistent pollutants are completely eliminated in 1975. The behavior of arable land.

fig_86a(; kwargs...)

Reproduce Fig 4.86a. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-14: policy run in which efforts to combat land erosion are initiated in 1975, in addition to the previous policies that eliminate the adverse effects of air pollution and persistent pollution. The behavior of land yields and food production.

fig_86b(; kwargs...)

Reproduce Fig 4.86b. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-14: policy run in which efforts to combat land erosion are initiated in 1975, in addition to the previous policies that eliminate the adverse effects of air pollution and persistent pollution. The behavior of arable land.

fig_87a(; kwargs...)

Reproduce Fig 4.87a. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-15: policy run in which the land required for urban and industrial use is reduced to 25 percent of expected requirements, in addition to the previous policies that combat land erosion and eliminate the adverse effects of air pollution and persistent pollution. The behavior of land yields and food production.

fig_87b(; kwargs...)

Reproduce Fig 4.87b. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-15: policy run in which the land required for urban and industrial use is reduced to 25 percent of expected requirements, in addition to the previous policies that combat land erosion and eliminate the adverse effects of air pollution and persistent pollution. The behavior of arable land.

fig_88a(; kwargs...)

Reproduce Fig 4.88a. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-16: equilibrium run in which the exogenous inputs level off in the year 2050. The behavior of land yields and food production.

fig_88b(; kwargs...)

Reproduce Fig 4.88b. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-16: equilibrium run in which the exogenous inputs level off in the year 2050. The behavior of arable land.

fig_89a(; kwargs...)

Reproduce Fig 4.89a. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-17: equilibrium run in which the exogenous inputs level off in the year 2025. The behavior of land yields and food production.

fig_89b(; kwargs...)

Reproduce Fig 4.89b. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-17: equilibrium run in which the exogenous inputs level off in the year 2025. The behavior of arable land.

fig_90a(; kwargs...)

Reproduce Fig 4.90a. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-18: equilibrium run in which the exogenous inputs level off in the year 2000. The behavior of land yields and food production.

fig_90b(; kwargs...)

Reproduce Fig 4.90b. The original figure is presented in Chapter 4 of DGFW.

Caption: Run 4-18: equilibrium run in which the exogenous inputs level off in the year 2000. The behavior of arable land.

Reproduce Fig 3.36. The original figure is presented in Chapter 3 of [DGFW](https://archive.org/details/dynamicsofgrowth0000unse).

Caption: Driving functions for the standard run of the capital sector.

fig_37(; kwargs...)

Reproduce Fig 3.37. The original figure is presented in Chapter 3 of DGFW.

Caption: Run 3-1: standard run of the capital sector with exogenous inputs.

fig_38(; kwargs...)

Reproduce Fig 3.38. The original figure is presented in Chapter 3 of DGFW.

Caption: Run 3-2: behavior of the capital sector when the average lifetime of industrial capital is increased from 14 to 21 years with standard inputs.

fig_39(; kwargs...)

Reproduce Fig 3.39. The original figure is presented in Chapter 3 of DGFW.

Caption: Run3-3: behaviorofthecapital sector when the capital-output ratio is decreased from 3 to 2 years with standard inputs.

fig_40(; kwargs...)

Reproduce Fig 3.40. The original figure is presented in Chapter 3 of DGFW.

Caption: Run 3-4: behavior of the capital sector when the industrial capital-output ratio is increased from 3 to 4 years with standard inputs. Note: Scales for IOPC, SOPC, and IO have been changed from their normal values.

fig_41(; kwargs...)

Reproduce Fig 3.41. The original figure is presented in Chapter 3 of DGFW.

Caption: Run 3-5: behavior of the capital sector when the fraction of capital allocated to obtaining resources is increased from 0.05 to 0.35 with other inputs at their standard values. Note: Scales for IOPC, SOPC, and IO have been changed from their normal values.

fig_42(; kwargs...)

Reproduce Fig 3.42. The original figure is presented in Chapter 3 of DGFW.

Caption: Run 3-6: behavior of the capital sector when the service capital-output ratio is increased from 1 to 2 years with standard inputs.

fig_43(; kwargs...)

Reproduce Fig 3.43. The original figure is presented in Chapter 3 of DGFW.

Caption: Driving functions for capital sector experiencing increasing resource costs.

fig_44(; kwargs...)

Reproduce Fig 3.44. The original figure is presented in Chapter 3 of DGFW.

Caption: Run 3-7: behavior of the capital sector when the fraction of capital allocated to obtaining resources increases after 1970.

fig_45(; kwargs...)

Reproduce Fig 3.45. The original figure is presented in Chapter 3 of DGFW.

Caption: Driving functions for capital sector undergoing increasing food. costs

fig_46(; kwargs...)

Reproduce Fig 3.46. The original figure is presented in Chapter 3 of DGFW.

Caption: Run 3-8: behavior of the capital sector when the fraction of industrial output allocated to agriculture increases after 1970.

fig_47(; kwargs...)

Reproduce Fig 3.47. The original figure is presented in Chapter 3 of DGFW.

Caption: Driving functions for a population decline in the capital sector.

fig_48(; kwargs...)

Reproduce Fig 3.48. The original figure is presented in Chapter 3 of DGFW.

Caption: Run 3-9: behavior of the capital sector when the population declines after 1970.

fig_25(; kwargs...)

Reproduce Fig 5.25. The original figure is presented in Chapter 5 of DGFW.

Caption: Run 5-1: standard run for the nonrenewable resource sector.

fig_26(; kwargs...)

Reproduce Fig 5.26. The original figure is presented in Chapter 5 of DGFW.

Caption: Run 5-2: Behavior of the sector with double the initial value of nonrenewable resources.

fig_28(; kwargs...)

Reproduce Fig 5.28. The original figure is presented in Chapter 5 of DGFW.

Caption: Run 5-3: The effects of cost-reducing technologies on the behavior of the nonrenewable resource sector.

fig_29(; kwargs...)

Reproduce Fig 5.29. The original figure is presented in Chapter 5 of DGFW.

Caption: Run 5-4: the effects of resource-conserving technologies on the behavior of the nonrenewable resource sector.

fig_30(; kwargs...)

Reproduce Fig 5.30. The original figure is presented in Chapter 5 of DGFW.

Caption: Run 5-5: The effects of zero population growth and advanced technological policies on the behavior of the nonrenewable resource sector.

fig_26(; kwargs...)

Reproduce Fig 6.26. The original figure is presented in Chapter 6 of DGFW.

Caption: Run 6-1: behavior of the pollution sector in response to a pulse input in persistent pollution generation in 1920.

fig_27(; kwargs...)

Reproduce Fig 6.27. The original figure is presented in Chapter 6 of DGFW.

Caption: Run 6-2: behavior of the pollution sector in response to a step increase and decrease in persistent pollution generation.

fig_28(; kwargs...)

Reproduce Fig 6.28. The original figure is presented in Chapter 6 of DGFW.

Caption: Inputs to Run 6-3, the historical run of the pollution sector.

fig_29(; kwargs...)

Reproduce Fig 6.29. The original figure is presented in Chapter 6 of DGFW.

Caption: Run 6-3: historical run of the pollution sector.

fig_30(; kwargs...)

Reproduce Fig 6.30. The original figure is presented in Chapter 6 of DGFW.

Caption: Inputs to Run 6-4 of the pollution sector when continued material growth is assumed.

fig_31(; kwargs...)

Reproduce Fig 6.31. The original figure is presented in Chapter 6 of DGFW.

Caption: Run 6-4: behavior of the pollution sector in response to continued material growth.

fig_32(; kwargs...)

Reproduce Fig 6.32. The original figure is presented in Chapter 6 of DGFW.

Caption: Run 6-5: behavior of the pollution sector with decreased toxicity indices.

fig_33(; kwargs...)

Reproduce Fig 6.33. The original figure is presented in Chapter 6 of DGFW.

Caption: Run 6-6: behavior of the pollution sector when the estimate of the persistent pollution transmission delay is doubled.

fig_34(; kwargs...)

Reproduce Fig 6.34. The original figure is presented in Chapter 6 of DGFW.

Caption: Run 6-7: behavior of the pollution sector when the estimate of the persistent pollution transmission delay is halved.

fig_35(; kwargs...)

Reproduce Fig 6.35. The original figure is presented in Chapter 6 of DGFW.

Caption: Run 6-8: behavior of the pollution sector when the assimilation half-life is assumed to increase twice as fast with a rising index of persistent pollution.

fig_36(; kwargs...)

Reproduce Fig 6.36. The original figure is presented in Chapter 6 of DGFW.

Caption: Run 6-9: behavior of the pollution sector when the assimilation half-life is assumed to be constant.

fig_37(; kwargs...)

Reproduce Fig 6.37. The original figure is presented in Chapter 6 of DGFW.

Caption: Run 6-10: behavior of the pollution sector in response to a doubling of the persistent pollution transmission delay in 1975.

fig_38(; kwargs...)

Reproduce Fig 6.38. The original figure is presented in Chapter 6 of DGFW.

Caption: Run 6-11: behavior of the pollution sector in response to an advance in persistent pollution assimilation technology in 1975.

fig_39(; kwargs...)

Reproduce Fig 6.39. The original figure is presented in Chapter 6 of DGFW.

Caption: Run 6-12: behavior of the pollution sector in response to a 50 percent increase in human health and land fertility technology in 1975.

fig_40(; kwargs...)

Reproduce Fig 6.40. The original figure is presented in Chapter 6 of DGFW.

Caption: Run 6-13: behavior of the pollution sector in response to a sudden increase in persistent pollution generation control technology in 1975.

fig_41(; kwargs...)

Reproduce Fig 6.41. The original figure is presented in Chapter 6 of DGFW.

Caption: Run 6-14: behavior of the pollution sector in response to adaptive persistent pollution generation control technologies when the persistent pollution transmission delay is assumed to be 20 years.

fig_43(; kwargs...)

Reproduce Fig 6.43. The original figure is presented in Chapter 6 of DGFW.

Caption: Run 6-15: behavior of the pollution sector in response to adaptive persistent pollution generation control technologies when the persistent pollution transmission delay is assumed to be 2 years.

fig_44(; kwargs...)

Reproduce Fig 6.44. The original figure is presented in Chapter 6 of DGFW.

Caption: Run 6-16: behavior of the pollution sector when persistent pollution generation stabilizes in the year 2000.

fig_45(; kwargs...)

Reproduce Fig 6.45. The original figure is presented in Chapter 6 of DGFW.

Caption: Run 6-17: behavior of the pollution sector when persistent pollution generation stabilizes in the year 2020.

fig_46(; kwargs...)

Reproduce Fig 6.46. The original figure is presented in Chapter 6 of DGFW.

Caption: Run 6-18: behavior of the pollution sector when adaptive persistent pollution generation control technologies are combined with material equilibrium in the year 2020.

fig_100(; kwargs...)

Reproduce Fig 2.100. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2- 15: constant total output, perfect fertility control, reduced desired family size.

fig_103a(; kwargs...)

Reproduce Fig 2.103a. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-18: maximum life expectancy of 100 years.

fig_103b(; kwargs...)

Reproduce Fig 2.103b. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-18: maximum life expectancy of 100 years.

fig_103c(; kwargs...)

Reproduce Fig 2.103c. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-18: maximum life expectancy of 100 years.

fig_84(; kwargs...)

Reproduce Fig 2.84. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-1: historical behavior, 1900-1975.

fig_85(; kwargs...)

Reproduce Fig 2.85. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2—2: historical behavior, 1900—1975, mortality variables.

fig_86(; kwargs...)

Reproduce Fig 2.86. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-3: historical behavior, 1900-1975, fertility variables.

fig_87(; kwargs...)

Reproduce Fig 2.87. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-4: constant low income.

fig_88(; kwargs...)

Reproduce Fig 2.88. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-5: constant high income.

fig_89(; kwargs...)

Reproduce Fig 2.89. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-6: constant low income, improved health care.

fig_90(; kwargs...)

Reproduce Fig 2.90. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-7: exponential economic growth.

fig_91(; kwargs...)

Reproduce Fig 2.91. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-8: exponential economic growth, mortality variables.

fig_93(; kwargs...)

Reproduce Fig 2.93. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-9: exponential economic growth, fertility variables.

fig_96(; kwargs...)

Reproduce Fig 2.96. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-11: exponential economic growth, perfect fertility control.

fig_97(; kwargs...)

Reproduce Fig 2.97. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-12: exponential economic growth, perfect fertility control, reduced desired family size.

fig_98(; kwargs...)

Reproduce Fig 2.98. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-13: constant total output.

fig_99(; kwargs...)

Reproduce Fig 2.99. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-14: constant total output, perfect fertility control.

fig_100(; kwargs...)

Reproduce Fig 2.100. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2- 15: constant total output, perfect fertility control, reduced desired family size.

fig_101a(; kwargs...)

Reproduce Fig 2.101a. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-16: constant total output, reference for sensitivity tests.

fig_101b(; kwargs...)

Reproduce Fig 2.101b. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-16: constant total output, reference for sensitivity tests.

fig_101c(; kwargs...)

Reproduce Fig 2.101c. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-16: constant total output, reference for sensitivity tests.

fig_102a(; kwargs...)

Reproduce Fig 2.102a. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-17: equitable food distribution and nutrition education.

fig_102b(; kwargs...)

Reproduce Fig 2.102b. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-17: equitable food distribution and nutrition education.

fig_102c(; kwargs...)

Reproduce Fig 2.102c. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-17: equitable food distribution and nutrition education.

fig_104a(; kwargs...)

Reproduce Fig 2.104a. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-19: greater allocations to health services.

fig_104b(; kwargs...)

Reproduce Fig 2.104b. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-19: greater allocations to health services.

fig_104c(; kwargs...)

Reproduce Fig 2.104c. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-19: greater allocations to health services.

fig_105a(; kwargs...)

Reproduce Fig 2.105a. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-20: no crowding effect.

fig_105b(; kwargs...)

Reproduce Fig 2.105b. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-20: no crowding effect.

fig_105c(; kwargs...)

Reproduce Fig 2.105c. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-20: no crowding effect.

fig_106a(; kwargs...)

Reproduce Fig 2.106a. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-21: constant maximum total fertility.

fig_106b(; kwargs...)

Reproduce Fig 2.106b. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-21: constant maximum total fertility.

fig_106c(; kwargs...)

Reproduce Fig 2.106c. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-21: constant maximum total fertility.

fig_107a(; kwargs...)

Reproduce Fig 2.107a. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-22: lower family size norm.

fig_107b(; kwargs...)

Reproduce Fig 2.107b. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-22: lower family size norm.

fig_107c(; kwargs...)

Reproduce Fig 2.107c. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-22: lower family size norm.

fig_108a(; kwargs...)

Reproduce Fig 2.108a. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-23: constant family size norm of 3.

fig_108b(; kwargs...)

Reproduce Fig 2.108b. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-23: constant family size norm of 3.

fig_108c(; kwargs...)

Reproduce Fig 2.108c. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-23: constant family size norm of 3.

fig_109a(; kwargs...)

Reproduce Fig 2.109a. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-24: increased social adjustment delay.

fig_109b(; kwargs...)

Reproduce Fig 2.109b. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-24: increased social adjustment delay.

fig_109c(; kwargs...)

Reproduce Fig 2.109c. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-24: increased social adjustment delay.

fig_110a(; kwargs...)

Reproduce Fig 2.110a. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-25: no income expectation effect.

fig_110b(; kwargs...)

Reproduce Fig 2.110b. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-25: no income expectation effect.

fig_110c(; kwargs...)

Reproduce Fig 2.110c. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-25: no income expectation effect.

fig_111a(; kwargs...)

Reproduce Fig 2.111a. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-26: increased compensation for perceived life expectancy.

fig_111b(; kwargs...)

Reproduce Fig 2.111b. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-26: increased compensation for perceived life expectancy.

fig_111c(; kwargs...)

Reproduce Fig 2.111c. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-26: increased compensation for perceived life expectancy.

fig_112a(; kwargs...)

Reproduce Fig 2.112a. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-27: decreased lifetime perception delay.

fig_112b(; kwargs...)

Reproduce Fig 2.112b. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-27: decreased lifetime perception delay.

fig_112c(; kwargs...)

Reproduce Fig 2.112c. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-27: decreased lifetime perception delay.

fig_113a(; kwargs...)

Reproduce Fig 2.113a. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-28: decreased fertility control effectiveness.

fig_113b(; kwargs...)

Reproduce Fig 2.113b. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-28: decreased fertility control effectiveness.

fig_113c(; kwargs...)

Reproduce Fig 2.113c. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-28: decreased fertility control effectiveness.

fig_84(; kwargs...)

Reproduce Fig 2.84. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-1: historical behavior, 1900-1975.

fig_85(; kwargs...)

Reproduce Fig 2.85. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2—2: historical behavior, 1900—1975, mortality variables.

fig_86(; kwargs...)

Reproduce Fig 2.86. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-3: historical behavior, 1900-1975, fertility variables.

fig_87(; kwargs...)

Reproduce Fig 2.87. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-4: constant low income.

fig_88(; kwargs...)

Reproduce Fig 2.88. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-5: constant high income.

fig_89(; kwargs...)

Reproduce Fig 2.89. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-6: constant low income, improved health care.

fig_90(; kwargs...)

Reproduce Fig 2.90. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-7: exponential economic growth.

fig_91(; kwargs...)

Reproduce Fig 2.91. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-8: exponential economic growth, mortality variables.

fig_93(; kwargs...)

Reproduce Fig 2.93. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-9: exponential economic growth, fertility variables.

fig_96(; kwargs...)

Reproduce Fig 2.96. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-11: exponential economic growth, perfect fertility control.

fig_97(; kwargs...)

Reproduce Fig 2.97. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-12: exponential economic growth, perfect fertility control, reduced desired family size.

fig_98(; kwargs...)

Reproduce Fig 2.98. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-13: constant total output.

fig_99(; kwargs...)

Reproduce Fig 2.99. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-14: constant total output, perfect fertility control.

fig_100(; kwargs...)

Reproduce Fig 2.100. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2- 15: constant total output, perfect fertility control, reduced desired family size.

fig_84(; kwargs...)

Reproduce Fig 2.84. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-1: historical behavior, 1900-1975.

fig_85(; kwargs...)

Reproduce Fig 2.85. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2—2: historical behavior, 1900—1975, mortality variables.

fig_86(; kwargs...)

Reproduce Fig 2.86. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-3: historical behavior, 1900-1975, fertility variables.

fig_87(; kwargs...)

Reproduce Fig 2.87. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-4: constant low income.

fig_88(; kwargs...)

Reproduce Fig 2.88. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-5: constant high income.

fig_89(; kwargs...)

Reproduce Fig 2.89. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-6: constant low income, improved health care.

fig_90(; kwargs...)

Reproduce Fig 2.90. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-7: exponential economic growth.

fig_91(; kwargs...)

Reproduce Fig 2.91. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-8: exponential economic growth, mortality variables.

fig_93(; kwargs...)

Reproduce Fig 2.93. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-9: exponential economic growth, fertility variables.

fig_94a(; kwargs...)

Reproduce Fig 2.94a. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-10: exponential economic growth, higher childbearing age.

fig_94b(; kwargs...)

Reproduce Fig 2.94b. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-10: exponential economic growth, higher childbearing age.

fig_94c(; kwargs...)

Reproduce Fig 2.94c. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-10: exponential economic growth, higher childbearing age.

fig_96(; kwargs...)

Reproduce Fig 2.96. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-11: exponential economic growth, perfect fertility control.

fig_97(; kwargs...)

Reproduce Fig 2.97. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-12: exponential economic growth, perfect fertility control, reduced desired family size.

fig_98(; kwargs...)

Reproduce Fig 2.98. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-13: constant total output.

fig_99(; kwargs...)

Reproduce Fig 2.99. The original figure is presented in Chapter 2 of DGFW.

Caption: Run 2-14: constant total output, perfect fertility control.

fig_10(; kwargs...)

Reproduce Fig 7.10. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-7: sensitivity of the initial value of nonrenewable resources to a doubling of NRI. To test the sensitivity of the reference run (Figure 7.7) to an error in the estimate of initial nonrenewable resources, NRI is doubled. As a result, industrialization continues for an additional 15 years until growth is again halted by the effects of resource depletion.

fig_11(; kwargs...)

Reproduce Fig 7.11. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-8: sensitivity of the initial value of nonrenewable resources to a tenfold increase in NRI. The initial value of nonrenewable resources NRI is increased by a factor of 10, to a value well outside its most likely range. Under this optimistic assumption, the effects of nonrenewable resource depletion are no longer a constraint to growth. Note that there is no dynamic difference in this run between setting resources at 10 times their reference value or assum¬ ing an infinite value of resources. However, population and capital con¬ tinue to grow until constrained by the rising level of pollution.

fig_13(; kwargs...)

Reproduce Fig 7.13. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-9: sensitivity of the fraction of industrial output allocated to agriculture. The slope of the fraction of industrial output allocated to agriculture FIOAA relationship is increased, reducing the time needed to redirect industrial output into or out of agricultural investment. This change has very little effect on the overall behavior of the model.

fig_14(; kwargs...)

Reproduce Fig 7.14. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-10: sensitivity of the average lifetime of industrial capital. The average lifetime of industrial capital ALIC is increased 50 percent over its value in the reference run (from 14 years to 21 years), causing capital to grow faster than in the reference run. Although the behavior mode of the model is unchanged, the model variables do not pass through their 1970 historical values. This parameter, as well as the other parameters in the capital growth loop, is an important factor in determining the growth rate of capital.

fig_15(; kwargs...)

Reproduce Fig 7.15. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-11: sensitivity of the average lifetime of industrial capital and the industrial capital-output ratio. As in the previous run, the average lifetime of industrial capital ALIC is increased from 14 to 21 years. To ensure that the model duplicates historical behavior, the industrial capital-output ratio ICOR is also increased (from 3 to 3.75). The resulting behavior is very similar to that of the reference run. Changes in the elements affecting capital growth, when constrained to produce behavior consistent with historical behavior, do not significantly affect the behavior of the model.

fig_16(; kwargs...)

Reproduce Fig 7.16. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-12: improved resource exploration and extraction technologies. The implementation of improved resource exploration and extraction technologies in 1975 is modeled by lowering the capital cost of obtaining resources for industrial production. This policy allows industrial production to continue growing for a few more years than in the reference run, but it is ineffective in avoiding the effects of resource depletion.

fig_17(; kwargs...)

Reproduce Fig 7.18. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-13: recycling technologies. The advances in resource exploration and extraction technologies of Run 7-12 are supplemented by an improvement in recycling technologies that reduces per capita resource usage by a factor of eight in 1975. That policy removes the constraining effects of resource depletion and allows population and capital growth to continue until checked by persistent pollution.

    fig_19(; kwargs...)

Reproduce Fig 7.19. The original figure is presented in Chapter 7 of [DGFW](https://archive.org/details/dynamicsofgrowth0000unse).

Caption: Run 7-14: resource and air pollution control technologies.
As resource technologies eliminate the resource constraint to growth,
industrial output continues to grow until it generates intolerable levels of
pollution. To decrease the constraining effects of pollution on the system,
Run 7-14 assumes that new air pollution control technologies are implemented in 1975. These additional technologies substantially reduce the
adverse effects of air pollution on land yield. However, land yield and
food per capita still decline, for the high index of persistent pollution
PPOLX decreases the land fertility. The improvement in air pollution
control technologies has solved only a small part of the pollution problem, for the rise in persistent pollutants ends growth in the other sectors of
the model.

fig_2(; kwargs...)

Reproduce Fig 7.2. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-1: population sector behavior, 1900-1970. Population POP increases over time at an average growth rate of 1.2 percent per year. Both the birth rate CBR and the death rate CDR decrease over the period, the former largely because of a lower desired total fertility DTF, and the latter primarily as a result of increased health services LMHS. Both trends occur as a result of industrialization.

fig_20(; kwargs...)

Reproduce Fig 7.20. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-15: resource and pollution technologies. Note: The scale for lOPC has been increased from 1,000 to 2,000 dollars per person-year. The resource arid air pollution control technologies of the previous run are augmented in 1975 by a technological policy that reduces by a factor of 10 the index of persistent pollution PPOLX 'generated by each unit of agricultural and industrial output. The lower level of pollution allows population and industrial output to continue to grow until the amount of available food becomes the constraining factor. The decline in food per capita FPC eventually causes a reduction in both population POP and industrial output per capita IOPC.

fig_21(; kwargs...)

Reproduce Fig 7.21. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-16: resource, pollution, and land yield technologies. Note: The scale of IOPC has been increased from 1,000 to 2,000 dollars per person-year. To increase food production, new agricultural technologies are implemented, augmenting the resource and pollution technologies of the previous run; they increase the land yield LY by a factor of 2 in 1975. This policy successfully raises the level of food in the short run, but in the long run the high yields cause increased land erosion, which later decreases the available food. After the year 2050 the higher rate of erosion depresses yields (and thus food per capita FPC) below the values observed in the previous run. As a result, population POP and industrial output per capita IOPC decline earlier than in Run 7-15, which assumed no new land yield technologies.

fig_22(; kwargs...)

Reproduce Fig 7.22. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-17: resource, pollution, and agricultural technologies. Note: The scale of IOPC has been increased from 1,000 to 8,000 dollars per person-year. The resource, pollution, and land yield technologies of the previous run are supplemented in 1975 by an improvement in land maintenance technologies. These new technologies ensure that higher land yields do not lead to any significant increase in land erosion. The reduced constraints in the resource, pollution, and agriculture sectors allow population POP and industrial output per capita IOPC to continue to grow until the effects of resource depletion are again evident, as in the reference run. Both population POP and industrial output per capita IOPC decline after the year

fig_23(; kwargs...)

Reproduce Fig 7.23. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-18: exponential changes in technology. Here it is assumed that exponentially increasing technologies are able to postpone indefinitely the effects of the constraints to growth, as modeled in World3, at no cost and with no delays in development and implementation. The improved technologies tend to reduce per capita resource usage and pollution generation per unit of agricultural and industrial output at 4 percent per year after 1975. At the same time, land yields tend to increase at 4 percent per year, with no upper limit and with practically no adverse side effects such as land erosion. Although industrialization grows exponentially, the rate of removal of land for urban-industrial use decreases to zero by the year 2000. Finally, air pollution is assumed to have no adverse effects on land yield. Under these assumptions, population reaches 14 billion people in the year 2100 and continues to grow (though at a slow rate of 0.6 percent per year). Food is in abundance throughout the run resource usage declines to zero as fewer resources are needed to sustain output, and industrial output per capita IOPC continues to grow indefinitely.

fig_24(; kwargs...)

Reproduce Fig 7.24. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-19: adaptive technological policies—no delays, no costs. Technological advances in reducing per capita resource usage, diminishing pollution, and increasing land yield are assumed to occur in response to a perceived need for the technologies. The maximum rate of change for each technology is assumed to be 5 percent per year. In addition, discrete advances in exploration and extraction technologies, land maintenance technologies, and air pollution technologies are assumed to be implemented in 1975. This run is similar in behavior to Run 7-18, in which technological improvements rise continuously at 4 percent per year. Growth is maintained through the year 2100 because of the absence of significant delays and costs in the development of new technologies.

fig_26(; kwargs...)

Reproduce Fig 7.26. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-20: adaptive technological policies—the effects of limitations to technological capabilities. The adaptive technological policies assumed in this run are identical to those in Run 7-19 except that the maximum rate of technological change is assumed to be 2 percent instead of 5 percent per year. Technology is unable to avoid the effects of the constraints to growth because industrial output per capita IOPC and population POP grow faster than the maximum rate of technological change. In this run, resource depletion again halts growth in population and industrial output.

fig_27(; kwargs...)

Reproduce Fig 7.27. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-21: adaptive technological policies—the effects of technological development and implementation costs. Here it is assumed that more effective recycling, pollution control, and land yield advances can be obtained only at increasing costs. These higher costs are represented in the model by a rise in the industrial capital-output ratio I COR. A trade-off now occurs between the benefits of continued growth and the costs of the technologies that make further growth possible. The rising costs of the new technologies cause industrial output per capita IOPC to decline after the year 2010.

fig_3(; kwargs...)

Reproduce Fig 7.3. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-2: capital sector behavior, 1900-1970. Industrial capital IC grows exponentially, causing industrial output IO to grow. Since their growth rate is greater than that of population, industrial output per capita IOPC also grows over the period, as do service output per capita SOPC and food per capita (not graphed). As development proceeds, (1) the fraction of output in agriculture FOA declines, (2) FOA is largely replaced by the increasing fraction of output in industry FOI, and (3) the fraction of output in services FOS remains relatively constant, near 50 percent of total output.

fig_30(; kwargs...)

Reproduce Fig 7.30. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-22: adaptive technological policies—the effects of delays and costs of technological development and implementation. Advances in recycling, pollution control, and land yield technologies are again assumed to be obtainable only at a finite cost. In addition, it is assumed that the benefits of these technologies will not be realized until 10 years after their initiation. As in Run 7-21, the rising costs, modeled as a rise in the industrial capital-output ratio ICOR, cause industrial output per capita IOPC to decline. The added costs incurred by the continued implementation of new technologies even after IOPC has peaked force IOPC to fall more precipitously than in Run 7-21.

fig_32(; kwargs...)

Reproduce Fig 7.32. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-23: adaptive technological policies—the effects of delays and costs,with a bias for continued growth in industrial output per capita. The previous run assumed that new recycling, pollution control, and land yield technologies are developed in response to a perceived need for them. Because of the time involved in technological development and implementation, however, these new technologies were effective only after a delay. Moreover, their development and implementation required additional capital, which increased the industrial capital-output ratio. In this run, the assumptions of Run 7-22 are augmented with a societal bias toward continued growth in industrial output per capita IOPC. Technological policies are implemented only as long as they do not hamper continued growth in IOPC. This policy is effective in continuing growth in the short run but counterproductive in the long run: the failure to implement the new technologies causes a significant depletion of resources and growth is ultimately terminated.

fig_34(; kwargs...)

Reproduce Fig 7.34. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-24: reduction of the desired completed family size. To reduce the pressures of population growth in the reference run, the desired completed family size is reduced to 2 children per family in 1975. Population POP continues to grow gradually for 70 years because of the delays inherent in the age structure. However, the effects of resource depletion again force the population to decline after 2040, as in the reference run. Since population growth is reduced, industrial output per capita IOPC and food per capita FPC rise more rapidly between 1975 and 2020 than in the reference run.

fig_35(; kwargs...)

Reproduce Fig 7.35. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-25: increase of industrial and service capital lifetimes. Both the average lifetime of industrial capital ALIC and the lifetime of service capital ALSC are increased 50 percent in 1975, thereby extending the productivity of capital. When implemented without additional policies to reduce the capital investment rate, this policy proves to be counterproductive in the long run. Compared with the reference run, the extension of product lifetimes allows industrial output to grow more rapidly, leading to a quicker depletion of resources. The rise in resource costs forces industrial output per capita IOPC to decline earlier than in the reference run.

fig_36(; kwargs...)

Reproduce Fig 7.36. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-26: shift in the choice of output forms. The amount of food and services desired by the population per unit of industrial output is increased by 50 percent in 1975. This shift in the choice of output slows the growth in industrial capital and industrial output, putting less pressure on the resource base. In the long run, however, the continually rising population POP thwarts the effectiveness of this policy, forcing a decline in industrial output per capita IOPC due to resource depletion.

fig_37(; kwargs...)

Reproduce Fig 7.37. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-27: population policy and shift of output choices. A combination of social policies that cause a reduction of growth both in population and in industrial capital is simulated in this run. In 1975 the desired completed family size is reduced to 2 children per family and the amount of services and food per unit of industrial output desired by the population is increased by 50 percent. The resulting behavior is substantially more stable than in the reference run, but the overshoot and decline mode is still evident. In World3, even these reduced levels of population and industrial capital cannot be sustained over the long term; new technological policies must be added to offset the effects of the limits to growth.

fig_38(; kwargs...)

Reproduce Fig 7.38. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-28: equilibrium through discrete policy changes. To obtain one example of a sustainable state of equilibrium, this run combines discrete policy changes in both technology and social values. To stabilize the population POP, the desired completed family size is reduced to 2 children per family in 1975. The growth in industrial capital is reduced in 1990 by reinvesting only enough industrial output to keep industrial output per capita IOPC at a constant level. In addition, new recycling and pollution control technologies are developed, capital lifetimes are increased, and social choices of output forms are shifted toward a preference for food and services. Population POP stabilizes in 2050 at 5 billion people, industrial output per capita IOPC levels off in 1990 at 350 dollars per person-year, and food per capita FPC stabilizes by the year 2000 at three times the subsistence level. The index of persistent pollution PPOLX is kept at very low levels, and the rate of resource depletion is slow enough to permit technology and industrial processes to adjust to changes in the availability of resources.

fig_39(; kwargs...)

Reproduce Fig 7.39. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-29: equilibrium through adaptive policies. Adaptive technological policies that increase resource recycling, reduce persistent pollution generation, and increase land yields are combined with social policies that stabilize population POP and industrial output per capita IOPC. The technological advances in recycling, pollution control , and land yields are assumed to be effective only after a delay and to require capital for their development and implementation. As in the adaptive technological runs described in section 7.5, additional technologies are assumed to be implemented in 1975. These policies lower resource costs, decrease the effects of air pollution, and reduce land erosion. The resulting model behavior reaches equilibrium because the stable population and capital reduce the need for new technologies. Thus the newly implemented technologies are less costly, and the delays in their development and implementation are less critical to their effectiveness.

fig_4(; kwargs...)

Reproduce Fig 7.4. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-3: agriculture sector behavior, 1900-1970. Increases in arable land AL and land yields LY cause a rise in food production over the historical period. The increase in land yields is primarily attributable to greater agricultural inputs per hectare AIPH (fertilizers, pesticides), for the land fertility LFERT remains nearly constant. Food per capita FPC also grows during the 70-year period but at a much slower rate than total food F, since the population is also increasing.

fig_41(; kwargs...)

Reproduce Fig 7.41. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-30: stabilization policies introduced in the year 2000. The combination of adaptive technological and social policies of the previous run are not introduced until the year 2000. The continuation of growth for an additional 25 years further erodes the carrying capacity of World3; therefore, the policies that led to equilibrium 25 years earlier are no longer effective.

fig_5(; kwargs...)

Reproduce Fig 7.5. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-4: nonrenewable resource sector behavior, 1900-1970. The rate of usage of nonrenewable resources NRUR grows exponentially at 4 percent per year over the historical period. This continuous increase is caused by the growth in both population POP and resource usage per capita PCRUM. Per capita resource usage rises as a result of industrial development. The increase in resource usage occurs at no additional increase in unit costs (see FCAOR in graph), in accordance with historical trends. In 1970, over 90 percent of the initial supply of nonrenewable resources remains to be used.

fig_6(; kwargs...)

Reproduce Fig 7.6. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-5: persistent pollution sector behavior, 1900-1970. The rate of generation of persistent pollutants PPGR increases exponentially as its two components, persistent pollutants generated from industrial output PPGIO and persistent pollutants generated from agricultural output PPG AO, rise over the 70-year period. After a 20-year delay, the persistent pollutant appearance rate PPAPR also rises, causing the index of persistent pollutants PPOLX to rise and eventually pass through its normalized value of 1.0 in 1970.

fig_7(; kwargs...)

Reproduce Fig 7.7. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-6A: World3 reference run. This is the World3 reference run, to be compared with the sensitivity and policy tests that follow. Both population POP and industrial output per capita IOPC grow beyond sustainable levels and subsequently decline. The cause of their decline is traceable to the depletion of nonrenewable resources. Runs 7-6B and 7-6C illustrate the mechanisms that force population POP and industrial output per capita IOPC to decline.

fig_8(; kwargs...)

Reproduce Fig 7.8. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-6B: capital sector variables from the reference run. This and the following run depict the mechanisms that forced population POP and industrial output per capita IOPC to decline in the preceding reference run (Figure 7.7). As resources are depleted, a larger fraction of capital must be allocated to obtaining resources FCAOR after the year 2000. FCAOR rises quite steeply because of the high rate of growth of the nonrenewable resource usage rate. The increase in FCAOR reduces the amount of capital allocated to producing industrial output so that both industrial output 10 and industrial output per capita 10PC decrease after the year 2015. The lower industrial output 10 causes a reduction in total agricultural investment TAI and therefore in the amount of agricultural inputs per hectare AIPH allocated to producing food.

fig_9(; kwargs...)

Reproduce Fig 7.9. The original figure is presented in Chapter 7 of DGFW.

Caption: Run 7-6C: agriculture sector variables from the reference run. As the level of agricultural inputs per hectare AIPH decreases after the year 2015 (Run 7-6B), land yield LY begins to fall. The resulting drop in food production causes food per capita FPC to decline after 2015. The lower food per capita FPC in turn reduces the lifetime multiplier from food LMF, which eventually raises the death rate and stops population growth.

fig_scenario1a(; kwargs...)

Reproduce the first subfigure of Scenario 1 from Chapter 4, page 133, in BTL.

Caption: The "Standard Run" from The Limits to Growth The world society proceeds along its historical path as long as possible without major policy change. Population and industry output grow until a combination of environmental and natural resource constraints eliminate the capacity of the capital sector to sustain investment. Industrial capital begins to depreciate faster than the new investment can rebuild it. As it falls, food and health services also fall, decreasing life expectancy and raising the death rate.

fig_scenario1b(; kwargs...)

Reproduce the second subfigure of Scenario 1 from Chapter 4, page 133, in BTL.

Caption: The "Standard Run" from The Limits to Growth The world society proceeds along its historical path as long as possible without major policy change. Population and industry output grow until a combination of environmental and natural resource constraints eliminate the capacity of the capital sector to sustain investment. Industrial capital begins to depreciate faster than the new investment can rebuild it. As it falls, food and health services also fall, decreasing life expectancy and raising the death rate.

fig_scenario2a(; kwargs...)

Reproduce the first subfigure of Scenario 2 from Chapter 4, page 135, in BTL.

Caption: Doubled Resources Are Added to Scenario 1 If we double the natural resource endowment we assumed in Scenario 1, industry can grow 20 years longer. Population rises to more than 9 billion in 2040. These increased levels generate much more pollution, which reduces land yield and forces much greater investment in agriculture. Eventually declining food raises the population death rate.

fig_scenario2b(; kwargs...)

Reproduce the second subfigure of Scenario 2 from Chapter 4, page 135, in BTL.

Caption: Doubled Resources Are Added to Scenario 1 If we double the natural resource endowment we assumed in Scenario 1, industry can grow 20 years longer. Population rises to more than 9 billion in 2040. These increased levels generate much more pollution, which reduces land yield and forces much greater investment in agriculture. Eventually declining food raises the population death rate.

fig_scenario1a(; kwargs...)

Reproduce the first subfigure of Scenario 1 from Chapter 4, page 169, in LtG30y.

Caption: Scenario 1: A Reference Point The world society proceeds in a traditional manner without any major deviation from the policies pursued during most of the twentieth century. Population and production increase until growth is halted by increasingly inaccessible nonrenewable resources. Ever more investment is required to maintain resource flows. Finally, lack of investment funds in the other sectors of the economy leads to declining output of both industrial goods and services. As they fall, food and health services are reduced, decreasing life expectancy and raising average death rates.

fig_scenario1b(; kwargs...)

Reproduce the second subfigure of Scenario 1 from Chapter 4, page 169, in LtG30y.

Caption: Scenario 1: A Reference Point The world society proceeds in a traditional manner without any major deviation from the policies pursued during most of the twentieth century. Population and production increase until growth is halted by increasingly inaccessible nonrenewable resources. Ever more investment is required to maintain resource flows. Finally, lack of investment funds in the other sectors of the economy leads to declining output of both industrial goods and services. As they fall, food and health services are reduced, decreasing life expectancy and raising average death rates.

fig_scenario1c(; kwargs...)

Reproduce the third subfigure of Scenario 1 from Chapter 4, page 169, in LtG30y.

Caption: Scenario 1: A Reference Point The world society proceeds in a traditional manner without any major deviation from the policies pursued during most of the twentieth century. Population and production increase until growth is halted by increasingly inaccessible nonrenewable resources. Ever more investment is required to maintain resource flows. Finally, lack of investment funds in the other sectors of the economy leads to declining output of both industrial goods and services. As they fall, food and health services are reduced, decreasing life expectancy and raising average death rates.