The United Nations Environment Programme (UNEP) unveiled its 2025 Champions of the Earth on Wednesday, celebrating five leaders whose work is reshaping climate policy, rebuilding ecosystems, and redefining what effective environmental action looks like. The annual award, considered the UN’s highest environmental honor, recognizes individuals and organizations whose contributions set new standards for ambition and impact.
UNEP Executive Director Inger Andersen emphasized the urgency of the moment, noting that the escalating consequences of climate change require “courageous leadership across every sector of society.” This year’s honorees reflect exactly that: a youth movement that secured a historic legal milestone for climate justice, a public servant pioneering climate-smart urban cooling, an architect elevating resilience through design, a research institution using AI to defend the Amazon, and a lifelong advocate for methane transparency.
Below is a closer look at the 2025 laureates and the transformative ideas they are advancing.
Pacific Islands Students Fighting Climate Change — Policy Leadership
When Cynthia Houniuhi appeared before the International Court of Justice, she spoke on behalf of millions living in climate-vulnerable island nations. Through the youth-led organization she co-founded, Pacific Islands Students Fighting Climate Change, Houniuhi helped secure an advisory opinion that clarified governments’ legal obligations to protect people from climate harm.
Their advocacy has electrified the global climate justice movement, demonstrating the power of youth leadership to shift international law and amplify the moral authority of frontline nations. The recognition signals a broader global acknowledgment that climate justice is integral to effective climate action.
Supriya Sahu, Government of Tamil Nadu — Inspiration and Action
In India’s Tamil Nadu state, Supriya Sahu is reshaping how communities adapt to intensifying heat. Her climate resilience strategy integrates ecological restoration, urban cooling solutions, and public infrastructure redesign. Under her leadership, initiatives to expand green cover and restore degraded ecosystems have supported millions of residents, while sustainable cooling programs have generated millions of green jobs.
Her work demonstrates how subnational governments can accelerate climate solutions at scale by mobilizing local communities, rethinking public services, and investing in nature-based resilience.
Mariam Issoufou, Niger/France — Entrepreneurial Vision
Architect Mariam Issoufou is leading a renaissance in climate-resilient design by rooting modern architecture in local wisdom. Her structures in Niger and across the Sahel rely on natural materials and passive cooling systems that dramatically reduce energy demand. Buildings like the Hikma Community Complex demonstrate that architecture can simultaneously honor cultural heritage, support communiy cohesion, and withstand extreme temperatures.
Issoufou’s work is inspiring a new wave of African architects who see design as a tool for sustainable development, resilience, and identity.
Imazon, Brazil — Science and Innovation
For decades, Imazon has been one of the Amazon’s most influential scientific watchdogs. The Brazilian research institute is now using artificial intelligence to forecast deforestation patterns, guide law enforcement, and improve governance across the world’s largest rainforest. Their geospatial tools have informed public policy, supported legal action against illegal deforestation, and provided unprecedented transparency on threats to forest ecosystems.
By bridging cutting-edge technology with environmental protection, Imazon is proving that data-driven approaches can accelerate conservation outcomes at national and regional scales.
Manfredi Caltagirone — Lifetime Achievement
Honored posthumously, Manfredi Caltagirone leaves behind a legacy defined by scientific rigor and global impact. As head of UNEP’s International Methane Emissions Observatory, he advanced transparency in one of the most critical yet under-addressed areas of climate action: methane mitigation.
Caltagirone helped build the foundation for stronger policies around methane reporting and reduction, contributing to major regulatory frameworks and driving collaboration between governments, industry, and scientific institutions. His work continues to shape the global response to one of the most potent greenhouse gases.
A Call to Scale What Works
As the international community prepares for pivotal climate and biodiversity negotiations in 2026, the 2025 Champions of the Earth offer a blueprint for what effective climate leadership looks like. Their work highlights a simple truth: scaling climate solutions is not only possible but already happening in communities, institutions, and design studios around the world.
UNEP’s latest cohort reminds policymakers and the public that innovation, courage, and collaboration remain the most powerful tools for building a livable future — and that transformative leadership often emerges from places and people the world is only just beginning to notice.
ORIGINAL ARTICLE: https://news.un.org/en/story/2025/12/1166558
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