Context:

Anthropic processes related to urban mobility have placed the issue of public transportation on the agenda of most countries in the world. In fact, compared to the private vehicle, it represents the most economical and sustainable way of exercising daily mobility. However, who use the internal combustion process, through petroleum derivatives, emit greenhouse gases and, therefore, this form of motoring mobility has become the biggest contributor to global climate change. Under this premise, the aim of this article is to analyze the externalities of greenhouse gas emissions in the public transportation of buses in the city of Tepic, Mexico.

Method:

The research uses data provided by the Nayarit Ministry of Environment; from which greenhouse gas emissions from public transportation were estimated using the 1996 methodology approved by the United Nations Intergovernmental Panel on Climate Change. In this sense, according to this methodology, which allows to estimate fuel consumption, the annual route was obtained by type of vehicle, as well as the vehicle's performance.

Results:

The greenhouse gas emissions in the city of Tepic, Mexico, approached 192 thousand tons emitted only by public transportation by bus. Although the granting of concessions has been carried out in a disorderly and arbitrary manner by the different governments, it was possible to provide an emission scenario for 2020.

Conclusions:

Public bus transportation in the city of Tepic faces accelerated growth, caused by the disorderly expansion of urban housing. This system has become one of the main emitters of greenhouse gases, which makes it a central issue for the implementation of public transportation policies, adopting initiatives and mechanisms to reduce emission levels, reduce externalities and contribute to the sustainability and mitigation of global climate change.