Another interesting and more recent research study investigates the relationship between hybrid classes, where a percentage of classes are online, and transportation-related CO2 emissions at a commuter campus. An increase in hybrid courses resulted in a decrease of student trips to campus and associated CO2 emissions (i.e. an increased percentage of online meetings by 10% caused an average reduction of 5 to 10000 daily kgs of CO2 emissions).
Clearly, transport contributes to local air pollution and emissions of greenhouse gases. As universities move toward more sustainable behaviors, reducing journeys to campus could become a priority for such Institutions.
Of course, hybrid and remote teaching are not perfect, environmentally speaking. There are hidden issues related to an increased use of technology: alas, going digital is not 100% green…Digital devices, like most technologies, also have an environmental impact: devices use electricity and are made of materials such as metals, glass, and plastics. These materials are be mined, manufactured, recycled, and disposed of.
It is easier to assess the impact that flying, travelling, and commuting have on climate change, while we are less likely to evaluate our digital behaviors in the same way. The transition to a greener and more sustainable future, which also includes digital
 Modeling the relationship between transportation-related carbon dioxide emissions and hybrid-online courses at a large urban university (SJSU), Matthew Little , Eugene Cordero , International Journal of Sustainability in Higher Education, 2014.