Earth’s Health Model Based on System Dynamics

Abstract

The earth is a complex network. This paper establishes a system dynamics network to measure the earths health.We set up a 3 layers network (earth layer, main system network and subsystem network). The earth layer reflects the global health condition directly. The main system network includes 4 interrelated elements (population, economy, resource and environment). The subsystem network includes elements in detail. We build the network based on the system dynamics, taking internal and external dynamic relations into account. We use the Simgua software to test and simulate our model. Parameters in global model are determined by historical data. Then, we simulate the global model and analyze the earths health trend. Besides, we introduce an evaluation model to forecast the tipping point and estimate the earths health. We get a fitting equation by multiple linear regression. This equation predicts and the tipping point. Health conditions are divided into 4 levels according to. Last, we use the Monte Carlo methods to analyze the sensitivity of nonrenewable resource and get that nonrenewable resources change makes a greatest impact on Industrial output.