Modeling population dynamics and economic growth as competing species: An application to CO2 global emissions

Since the beginning of the last century the world is experiencing an important demographic transition, which will probably impact on economic growth. Many demographers and social scientists are trying to understand the key drivers of such transition as well as its profound implications. A correct understanding will help to predict other important trends of the world primary energy demand and the carbon emission to the atmosphere, which may be leading to an important climate change. This paper proposes a set of coupled differential equations to describe the changes of population, gross domestic product, primary energy consumption and carbon emissions, modeled as competing-species as in Lokta-Volterra prey-predator relations. The predator–prey model is well known in the biological, ecological and environmental literature and has also been applied successfully in other fields. This model proposes a new and simple conceptual explanation of the interactions and feedbacks among the principal driving forces leading to the present transition. The estimated results for the temporal evolution of world population, gross domestic product, primary energy consumption and carbon emissions are calculated from year 1850 to year 2150. The calculated scenarios are in good agreement with common world data and projections for the next 100 years.Population dynamics, economic growth, primary energy consumption, carbon emission model, Lokta-Volterra Equations, Prey-predator model.

Stochastic environmental effects, demographic variation, and economic growth

We consider a stochastic environment to study interactions among pollution growth, demographic changes, and economic growth. Drawing on the empirical findings of slow convergence patterns of pollution shocks (viz., with a long-memory), we build an analytical framework where stochastic environmental feedback effects on population changes are reflected upon aggregate economic growth. Long-memory in economic growth, in our model, is shown to arise due to the inherent stochasticity in environmental and demographic system. Empirical results for a set of developed and developing countries generally support our conjecture. Simulation experiment is carried out to lend additional support to this claim.Environmental Quality, Long-memory, Demographic Dynamics, Economic Growth

On the Beach? Sustainability, Optimal Pollution, and Optimal Population

Is it possible that the utility maximizing behavior leads the mankind to destruction? We develop a model with optimal pollution and optimal population in which population growth rate decreases along with pollution. We study if the optimal path is demographically sustainable, i.e. if it can provide non-decreasing consumption for a non-decreasing population. We find that demographic sustainability is impossible without technical progress. Technical progress, however, does not necessarily lead to demographically sustainable growth.

Growth on a Finite Planet: Resources, Technology and Population in the Long Run

We study the interactions between technological change, resource scarcity and population dynamics in a Schumpeterian model with endogenous fertility. There exists a pseudo- Malthusian equilibrium in which population is constant and income grows exponentially: the equilibrium population level is determined by resource scarcity but is independent of technology. The stability properties are driven by (i) the income reaction to increased resource scarcity and (ii) the fertility response to income dynamics. If labor and resources are substitutes in production, income and fertility dynamics are self-balancing and the pseudo-Malthusian equilibrium is the global attractor of the system. If labor and resources are complements, income and fertility dynamics are self-reinforcing and drive the economy towards either demographic explosion or human extinction. Introducing a minimum resource requirement, we obtain a second steady state implying constant population even under complementarity. The standard result of exponential population growth appears as a rather special case of our model.Endogenous Innovation, Resource Scarcity, Population Growth, Fertility Choices

Population ageing and endogenous economic growth

This article investigates the consequences of population ageing for longrun economic growth perspectives. We introduce population ageing into a generalized model of endogenous technological change incorporating the model of Romer (1990) and Jones (1995) as special cases. We find that increases in longevity have positive effects on steady state per capita output growth in endogenous as well as in semiendogenous growth models. In the latter case, the positive dependence can also be shown for the equilibrium growth rate during transition to the steady state.population ageing, endogenous technological change, long-run economic growth.

Population aging and endogenous economic growth

This article investigates the consequences of population aging for long-run economic growth perspectives. We introduce age specific heterogeneity of households into a model of research and development (R&D) based technological change. We show that the framework incorporates two standard specifications as special cases: endogenous growth models with scale eects and semi-endogenous growth models without scale effects. The introduction of an age structured population implies that aggregate laws of motion for capital and consumption have to be obtained by integrating over different cohorts. It is analytically shown that these laws of motion depend on the underlying demographic assumptions. Our results are that (i) increases in longevity have positive effects on per capita output growth, (ii) decreases in fertility have negative effects on per capita output growth, (iii) the longevity effect dominates the fertility eect in case of endogenous growth models and (iv) population aging fosters long-run growth in endogenous growth models, while the converse holds true in semiendogenous growth frameworks.population aging, endogenous technological change, longrun economic growth

Demographic Transition Environmental Concern and the Kuznets Curve

In an endogenous growth model with pollution and abatement we characterize the socially optimal solution. We find that the rate of growth depends negatively on the weight of environmental care in utility and positively on the population growth rate. We also find a trade-off between growth and environmental quality beyond which an environmental Kuznets curve is derived in the long term. This one emerges from the implications of the demographic transition for the rate of population growth, and the accompanying variation in the willingness to pay for environmental quality as the economy develops.Optimal Growth; Environment; Population Growth; Preferences

System Dynamics Implementation of a Model of Population and Resource Dynamics with Adaptation

We build and analyze a dynamic ecological economic model that incorporates endogenous innovation on input substitutability. The use of the system dynamics method allows us to depart from conventional equilibrium thinking and conduct an out-of-equilibrium (adaptation) analysis. Simulation results show that while improvement in input substitutability will expand an economy, this change alone may not improve sustainability measured by indicators such as utility-per-capita and natural resource stock. It could, however, be possible that in combination with other technological progress, improvement in input substitutability will contribute to sustainable development. Sensitivity analysis also indicates a possible complication with the use of exogenous consumer preference, which is often assumed in standard economics