City comptroller’s climate chief takes green office role
Louise Yeung, former climate chief for NYC Comptroller Brad Lander, becomes Mamdani’s chief climate officer heading the Mayor’s Office of Climate and Environmental Justice. The appointment, announced December 31, 2025, puts an experienced green policy advocate in charge of the city’s climate strategy. Yeung previously directed resiliency at the Department of Transportation and served as vice president of energy at the city’s Economic Development Corporation, giving her broad municipal sustainability experience.
Climate Office Background
The Mayor’s Office of Climate and Environmental Justice coordinates citywide climate policy, renewable energy transition, building efficiency, and environmental justice initiatives. Under de Blasio, this office was led by someone who doubled as DEP commissioner, mixing environmental protection with climate strategy. Mamdani has separated the roles, creating distinct climate and environmental agencies.
Climate and Environmental Justice Mandate
Yeung will oversee pursuit of NYC’s climate commitments: reducing greenhouse gas emissions, transitioning to renewable energy, improving building efficiency, and protecting communities from environmental hazards. The office coordinates across agencies to ensure climate considerations inform all city decisions.
Green Infrastructure and Equity
Environmental justice means ensuring that low-income communities and communities of color are not disproportionately burdened by pollution, hazardous facilities, or excluded from green benefits. Yeung will work to ensure green investments benefit all communities, not just wealthy areas. This involves strategic infrastructure placement and community benefit agreements.
Building Efficiency and Emissions
NYC buildings account for roughly 70 percent of city greenhouse gas emissions. Building efficiency improvementsinsulation, heating system upgrades, renewable energy installationreduce emissions but require capital investment. Yeung will oversee programs incentivizing or requiring building improvements while ensuring costs don’t displace low-income residents.
Climate Resilience and Adaptation
Beyond emissions reduction, the city must adapt to climate change already underway: sea level rise, extreme weather, temperature increases. Yeung will coordinate resilience planning involving infrastructure adaptation, emergency preparedness, and community protection. For climate information, see the NYC Sustainability Office. Learn about environmental justice at EPA’s Environmental Justice Mapper. Read climate strategy at C40 Cities Climate Leadership Group. Understand green building at U.S. Green Building Council.
