Arnold is a Research Fellow at the Centre for Crop and Disease Management, Curtin University. He is an environmental scientist with more than 15 years of research experience in agriculture, natural resource, applied climate science, human ecology, quantitative geography, and geographic information system. In 2021, he was awarded as one of the Outstanding Young Scientists by the National Academy of Science and Technology (Philippines) for his contribution to the advancement of human ecological research in the country. He is the founding Editor-in-Chief of the Journal of Human Ecology and Sustainability and also serves on the Editorial Board of PeerJ, Spatial Information Research and, SN Social Sciences.