Bryce is the Legal Advisor to the Chair of the Alliance of Small Island States (AOSIS) at the United Nations. AOSIS, currently chaired by Samoa, is the negotiating group on climate change, sustainable development, and oceans issues for the 39 small island developing states around the world. He has been legal advisor since 2013 and participated in the negotiation of the Paris Climate Agreement, focusing on institutional and compliance issues, and the incorporation of non-state actors into the international agreement. In addition, he directs the AOSIS Fellowship, a SIDS-designed capacity building and policy empowerment program that brings early career SIDS diplomats to New York and UN Headquarters for a year of training and practical experience in their diplomatic missions.

On the academic side, he is the Director of the United Nations Diplomacy Clinic and Adjunct Professor of Law at the NYU School of Law. He teaches International Environmental Law, Global Environmental Governance, and UN Diplomacy. He has authored a number of articles and a book, focusing on the governance of global environmental problems and the incentives and legal and institutional regimes created to manage these problems.

He has an LLM in International Law from NYU Law, a JD from the University of Toronto, and a BSc in Biology from McMaster University. He practiced private international law in Toronto and was a policy expert and advocate for higher education.