Madeleine MacGillivray (she/her) is a lifelong climate justice advocate and science communicator. At nine she founded her first project, Superheroes Needed, to empower individuals to realize our powers to fight for our right to a livable climate, to hold the powers that be accountable, and to build resilient and vibrant communities. At 15, Madeleine appeared as one of six youth plaintiffs as part of the Our Children’s Trust lawsuit, which sued the US government and the EPA and reached the Supreme Court.

Madeleine is the Climate Communications and Policy Coordinator at Seeding Sovereignty, where she educates and organizes at the intersection of plastics and climate. She hosts a podcast called Supersede, which answers the big collective question, "What can I do to further climate justice?” by featuring passionate climate doers across all sectors who have found their climate superpowers. As an Ambassador and advisory board member of the 5Gyres Institute, Madeleine specializes in microplastics pollution research and legislation.

Madeleine holds an MS in Sustainability Management at Columbia University’s School of Professional Studies and a BA in Environmental Policy from Barnard, having completed her undergraduate thesis on microplastics pollution at Columbia's renowned Lamont-Doherty Earth Observatory. 

Madeleine has spoken at countless events globally and continues to use her voice in podcast, article, and social media features. She has delivered keynote talks in Sydney, led workshops at Cornell and FIT, spoken at San Francisco Earth Day, and hosted conversations for UN Fashion x Oceans. Madeleine passionately communicates complex environmental issues with creativity, compassion, and empathy. She’s a proud Brooklyn native.