<p>Carbon dioxide is the primary greenhouse gas contributing to global warming. Meanwhile, vegetation plays a crucial role in reducing atmospheric CO₂ levels. In the yesteryears, human activities have led to a global decline in plant biomass. This study presents a deterministic mathematical model to investigate the influence of low-density forest biomass on elevated CO₂ emissions. We investigate the positivity and boundedness of solutions, along with the local and global stability behaviors of the equilibria. In addition, we analyze the emergence of Hopf and transcritical bifurcations within the system. Numerically, we conduct sensitivity analysis and parameter estimation. We identify critical thresholds that act as early warning indicators of environmental degradation, supporting proactive policy measures to preserve ecological balance. The model is further extended to a stochastic framework by incorporating environmental fluctuations, where we establish the existence of a unique global positive solution. The impact of stochastic noise on system dynamics and the potential for extinction due to environmental variability are also explored. Overall, our study quantifies the interactions between atmospheric CO₂, human population, and forest cover, offering a framework to evaluate climate change mitigation through afforestation and reduced anthropogenic emissions.</p>