The annual Neuroscience meeting yields significant, measurable impacts that conflict with the environmental commitment of the society and IPCC’s recommendations to address the climate emergency (IPCC, 2018). We used 12,761 presenters’ origins, two online carbon calculators, and benchmark values to estimate 2018 meeting-related travel, event venue operations, and hotel accommodation emissions. Presenters’ conference travel resulted in between 17,298 and 8,690 t CO2, with or without radiative forcing index factors. Over 92% of authors traveled by air and were responsible for over 99% of total travel-related emissions. Extrapolations based upon 28,691 registrants yielded between 69,592.60 t CO2e and 38,010.85 t CO2 from travel. Comparatively, authors’ and registrants’ hotel accommodation emissions equaled 429 and 965 t CO2e, whereas operation of the San Diego Convention Center equaled about 107 t CO2e. We relate SfN meeting-related emissions to potential September Arctic sea ice loss, labor productivity loss ...