In 2011 Peter Kalmus calculated the carbon emissions associated with his personal and professional activities for his previous year as a postdoc at Caltech. The climate scientist at NASA’s Jet Propulsion Laboratory found that his air travel to two international and half a dozen domestic conferences accounted for more than two-thirds of his annual emissions.
Physics Today 72, 9, 29 (2019); https://doi.org/10.1063/PT.3.4291