Purpose: This study aims to investigate patterns in international travel behavior of scientific staff depending on the categories of gender, scientific field and scientific seniority level. The learning from salient differences possibly revealed may inform measures for reducing travel greenhouse gas (GHG) emissions, especially for high-emitting staff groups, and help strengthen the equality between scientists of different categories concerning their travel behavior. Design/methodology/approach: The study collected and used novel empirical data on travel GHG emissions from University of Graz scientific staff for five consecutive years (2015-2019) and used statistical analysis and inference to test and answer three distinct research questions on patterns of travel behavior. Findings: The travel footprint of scientific staff, in terms of annual GHG emissions per scientist, exhibits various highly significant differences across scientific fields, seniority and gender, such as male senior natural scientists showing ten times higher per-person emissions than female junior social scientists. Originality/value: The five-year travel GHG emissions data set across all fields from natural sciences via social sciences to humanities at a large university (Uni Graz, Austria, about 2,000 scientific staff) and across seniority levels from predocs to professors, both for female and male scientists, enabled a robust empirical study revealing distinct differences in travel GHG footprints of academic staff. In this way, the study adds valuable insights for higher research institutions toward effective GHG reduction policies.