The requirement for methodological advancements in research as a critical instrument for rapid and improved understanding of dynamic and heterogeneous behavior in socio-environmental systems is developing. The research examined the green house gas (GHG) emissions and mitigation rates, as well as their impact on the human occupants of two megacities, Metro Manila in the Philippines and New York City in the United States of America. We developed a basic framework for methodical development of agent-based simulations using NETLOGO version 5.2.1. The introduction of factual data was followed by consideration of its application to a dynamic model of GHG emissions and their influence on the human population in light of implemented mitigation initiatives. With a margin of error of around 7%, the model was shown to be reliable in estimating the livability of the two megacities. Metro Manila's livability score is 6% greater than that of New York City. The findings are highly disturbing, implying a greater human population involvement in GHG mitigation measures, given that cities' livability is mostly determined by population expansion. However, it should be highlighted that the probability of population engagement should not exceed the carrying capacity of an ecosystem.