Mathematical Modeling and Analysis of Atmospheric Carbon Dioxide (CO2) Dynamics with Human Population Growth and Vehicle Services Age

In this study, we propose a mathematical model for the dynamics of atmospheric carbon dioxide (CO2) with human population growth and an age-structured vehicle population. The positivity and boundedness of the model’s solutions are verified, and the global stability of an interior equilibrium point is proved. We calibrate the model parameters using the least-squares method. Simulations of the model show good alignment with the reported atmospheric CO2 data. Moreover, the sensitivity analysis shows that human-related emission factors and emissions from old vehicles are the main contributors to CO2 accumulation. The results of this study recommend that reducing anthropogenic emissions, accelerating the retirement of old vehicles, and strengthening carbon sequestration initiatives be considered to mitigate future atmospheric CO2 accumulation.