Gregory is Director of Research and Data Integrity, working on the Research, Data, and Innovation team to oversee the WRI peer review process for publications and data products.

Prior to joining WRI, Gregory worked as a research scientist in Tromso and Oslo, Norway at the Norwegian Forest and Landscape Institute, renamed the Norwegian Institute of Bioeconomy Research (NIBIO) during his tenure there. Gregory led a small research group there, secured research funding, and published on topics related to land use change, agriculture and landscape monitoring, remote sensing methodology, invasive species management, biodiversity, ecological restoration, and refugee integration. Prior to this, he was Assistant Professor of geography at the University of Memphis, where he mentored and advised graduate and undergraduate students; taught in the areas of GIS, remote sensing, statistics, and world regional geography; developed and oversaw curricula for bachelor, master's, PhD, and certificate programs in geography; led and oversaw study abroad programs; and conducted research on similar topics to his work in Norway.

Gregory holds a PhD in geography from the University of North Carolina at Chapel Hill, an M.A. in statistics from Columbia University, and an A.B. in mathematics from Dartmouth College. Gregory was awarded a Fulbright student fellowship to conduct dissertation research on park management in Latvia, and a subsequently a Fulbright specialist award to teach GIS and conduct research on invasive species in Latvia.

In his spare time, Gregory enjoys playing piano and table tennis, swimming, and traveling.