Gabriel Lewenstein serves as Senior Manager for North American Communications and Public Affairs at C40. In this capacity, he works with mayors and cities to use communications tools to advance climate action. This includes liaising with mayoral communications teams, identifying opportunities for action and leadership, and highlighting case studies and stories on climate leadership by cities.
Before joining C40, Gabriel worked in city and state government, serving as Chief of Staff to a state legislator, where he managed a legislative portfolio addressing environmental issues, criminal justice reform, and LGBTQ rights. Prior to that, Gabriel worked at the Institute for Transportation and Development Policy, coordinating with cities around the globe to highlight and advance the creation of sustainable cities.
Gabriel graduated from Tufts University with a degree in International Relations and a focus on urban environmental issues. He is passionate about creating sustainable, equitable, and vibrant cities. In his spare time, he enjoys puns, board games, and baking, and has a lifelong passion for elephants.
Gabriel Tenenbaum is C40 Director of Implementation for Latin America and holds twelve years of experience working with climate action and sustainability in the region. He has a Masters in Transport Engineering from the Federal University of Rio de Janeiro, Brazil, and in Generalist Engineering from École Centrale de Lyon, France.
Gabriel is responsible for the operations of all regional programmes, including UCAP CAI, Laneshift, Breathe Cities, ZEBRA, TUMI, and for ensuring that regional work is coordinated with C40’s global strategy, increasing C40 technical support to cities effectively.
Before this role, Gabriel was C40’s Head of Zero Emission Vehicles, managing The Climate Pledge Laneshift Initiative for freight decarbonisation and the ZEBRA Partnership for zero-emission bus implementation in the region. Gabriel’s relationship with C40 started in 2018 when he joined the organization as Mass Transit Network Manager, and then as the ZEBRA Programme Manager in 2019. He spent 2 years at the Rio de Janeiro Transport Department from 2021 to 2023, leading the promotion of governance reform in the city public transport system before returning to C40. Before C40, Gabriel worked at other public, non-profit and private sector organisations focusing on transport and infrastructure.
Gabriela is C40’s Head of Zero Emission Vehicles, leading regional efforts to accelerate the adoption of zero-emission transport across cities in Latin America. She led the Laneshift Initiative, in partnership with The Climate Pledge, focused on freight decarbonization, and supported the ZEBRA Partnership, to zero-emission buses adoption in major cities across the region. She joined C40 and served as the Senior Programme Manager for zero-emission freight, supporting six cities in the region by coordinating and overseeing programme implementation.
Before joining C40, she led the “TUMI E-Bus Mission” at the World Resources Institute (WRI), supporting cities in Mexico and Colombia to scale up e-bus adoption from an inclusive approach, focusing on the social and health benefits for women drivers, workers and users. She served as Research and Gender Policy Lead at the IMEPLAN (Metropolitan Planning Institute) in Guadalajara, where she integrated gender and social inclusion into metropolitan planning policies and programs. In 2014, she collaborated with Mexican artist Gilberto Aceves Navarro on the urban art exhibition “Las Bicicletas,” which promoted urban cycling and the development of healthy and safer cities in Mexico and the United States.
With over 14 years of experience, Gabriela has worked closely with local governments in Mexico and Latin America to shape sustainable mobility policies, metropolitan governance and promote sustainable transport systems, always with a strong emphasis on gender equality and social inclusion.
Gabriela holds a Master’s in Governance, Development and Public Policy from the Institute of Development Studies (IDS) at the University of Sussex, and a Bachelor’s in International Relations from ITESO University. She is also a fellow of the “Leadership, Urban Mobility and Gender” program for women leading change in Latin America. Her passion for literature written by women, music, and design inspires her vision of more resilient and equitable cities, where culture plays a central role in urban transformation.
Georgina serves as Director of Operations for the GCoM x C40 Joint Program. She leads the operational support to the Management Team to ensure effective strategic and operational planning and decision-making. She supports the Deputy Executive Director across a range of activities, such as fundraising and partnership support, and manages select projects on his behalf. Gina has previously worked on the delivery of C40’s role in the 2018 Global Climate Action Summit, including the development of new sectoral declarations. Before joining C40, Gina worked for the Coalition for Urban Transitions supporting the development of new strategic partnerships and governmental diplomacy efforts and managing engagement activities, such as events at international conferences. Gina was formerly a corporate lawyer in the City of London, with a focus on mergers and acquisitions. She holds an MSc (Environmental Policy and Regulation) from the London School of Economics, postgraduate qualifications in law from BPP Law School and a BA Hons (English and French) from the University of Warwick.
Gideon serves as C40’s Project Manager, Air Quality Policy and Analysis. In this role, he works to define impact actions from air quality, health, and climate data analysis. He also supports the development and maintenance of C40 air quality analysis tools.
Before joining C40, Gideon worked at the United Nations Environment Programme and AirQo, Makerere University. As the International Network Operations Liaison at AirQo, Makerere University, he liaised with network partners to establish and strengthen air quality monitoring networks in African cities, specifically focusing on developing and deploying low-cost sensors.
Gideon holds an MSc in Electrical Engineering from the University of Rostock (Germany) and a BSc in Electrical and Electronic Engineering from Dedan Kimathi University of Technology (Kenya).
As Head of Inclusive Climate Action (ICA), Giovanni is responsible for the ICA team’s policy development, research, advocacy and global leadership functions. Giovanni joined C40 in 2021 as Senior Manager for Climate & Migration to establish and deliver the C40-MMC Global Mayors Task Force, in partnership with the Mayors Migration Council (MMC), and other activities related to climate migration and inclusive climate action.
Prior to C40, Giovanni served as Deputy-Chief Resilience Officer for the City of Barcelona, working on the development of the city’s urban resilience strategy, with a strong focus on affordable housing, economic inclusion, migration and inclusive climate action. Before that, he served as an Urban Resilience Specialist for UN-Habitat, supporting the development and implementation of a City Resilience Profiling Tool in several regions across the globe.
Giovanni has a BA in Architecture and Planning from the Polytechnic School of Milan; he holds an MSc in Middle East Politics from the London School of Oriental and African Studies (SOAS), and a Master in Public and Social Policy from the Pompeu Fabra/Johns Hopkins University.
As the Head of Data Systems, Regions and Partnerships, Giovanni drives the global development and adoption of a centralised data platform and AI-driven initiatives for the GCoM alliance and C40 Cities. He leads targeted regional engagement, cultivates key partnerships, and oversees strategic coalitions at the nexus of technology and climate to accelerate city-led implementation.
Giovanni’s journey with C40 began in 2018 as an intern in the Regions team. He subsequently spent over five years within the Business Planning & Reporting team, progressing through roles as Officer, Manager, and Senior Manager. During this time, he led major organisational projects, including managing the Leadership Standards monitoring & evaluation processes and coordinating the end-to-end development of the C40 Business Plan 2025-2030. He also managed the annual CDP reporting process and delivered technical assistance to strengthen city data systems.
Giovanni holds a degree in Political Science from the University of Bologna and an MSc in Environmental Management from the University of Reading.
Gloriela is the C40 Manager of US Health, Climate, and Equity. In this role, she collaborates with six US cities working on initiatives at the intersection of public health, climate change, and social equity to facilitate peer learning and co-create public-facing deliverables to amplify implementation lessons.
Before joining C40, she co-led and co-designed evaluations of social service programs and provided technical assistance to improve service delivery for low-income people at MDRC as a qualitative social policy researcher. Her work experience covers multiple institutions, including public housing authorities, community colleges, financial counselling centres, and philanthropic organizations. She also served as the Justice, Equity, Diversity, and Inclusion Advocacy Council Chair working with organizational leadership and employees to set and advance goals towards improved workplace practices and equity-centred research methods.
Gloriela has a degree from the University of Michigan – Ann Arbor in Public Policy with a focus on Environmental Justice and Health Policy at the Gerald R. Ford School of Public Policy.
Outside work, she loves dancing, practising yoga and mindfulness, walking in nature with friends and family, and being anywhere in her beloved Puerto Rico.
As C40’s Regions & Mayoral Engagement Officer, Gowri supports day-to-day operations and global milestone events of the cross-regional mayoral network through stakeholder engagement, communication, and data management.
Prior to joining C40, Gowri worked as a Research Assistant in Sustainability and Resilience at UCL Consultants, where she was involved in the World Road Association (PIARC) project on road transport resilience and decarbonization strategies. At the Centre for Policy Research (CPR), she interned with the Scaling City Institutions for India Initiative (SCI-FI), supporting city authorities in developing sustainable water and sanitation solutions for urban poor areas.
A Commonwealth Master’s Scholar, Gowri holds an MSc in Urbanisation and Development from the London School of Economics and a BA (hons) in Sociology from the University of Delhi.
Grace is an experienced strategic leader with a 16-year track record spanning African local government operations and the US private sector. While working at County Government of Machakos (Kenya), she designed and executed sustainable development programmes across multiple departments and stakeholders. She set up the Machakos Climate Change Unit and supported the department in drafting the Climate Act, finance and climate change policies, and securing funding for the financial locally-led Climate Action Program.
Grace holds a Doctor of Business Administration from California Southern University and has a certification in Monitoring and Evaluation. Grace is also passionate about empowering the girl child and actively volunteers in her community, providing mentorship to support young girls. In her spare time, she loves spending time with her family, hiking, and cooking.
Guilherme Macieira serves as C40’s Project Assistant for the Zero Emission Bus Rapid-Deployment Accelerator (ZEBRA) project, led by C40 Cities and the International Council on Clean Transportation (ICCT). In this role, Guilherme supports the coordination and delivery of the programme, through administrative tasks, communication activities, and sharing best practices for deploying zero-emission buses in Latin America.
Before joining C40, Guilherme worked as an Institutional Relations and Advocacy intern at ICLEI South America, where he developed a keen interest in urban climate action, supporting the engagement of mayors and city representatives at COP26 and other international forums and implemented projects focused on climate justice and climate action. Guilherme has also worked at Solidarity Center, an international workers’ rights organisation, implementing cooperation projects with local unions to strengthen the collective voice of workers, especially underrepresented groups, around the world.
Based in Rio de Janeiro, Brazil, Guilherme holds a B.A. in International Relations from the Federal University of São Paulo, where he focused on international public policies and cooperation.
Guillermo is the Technical Head for Breathe Cities in Latin America, responsible for coordinating the programme implementation in Mexico City, Rio de Janeiro and Bogotá. Before this role, he was the Inclusive Climate Action Senior Manager, UCAP CAI/CFF, supporting the integration of inclusive climate action across different C40 programmes.
Before C40, he worked in different public sector roles in Mexico and Australia. He lived over six years in Melbourne (Australia) where he studied urban planning and had the opportunity to work in designing sustainable transport policies across different government settings, including the Victorian Parliament, Glen Eira City Council, and the Victoria State Government.
In Mexico, he worked for over five years in the departments of the environment at Guadalajara City Council and Jalisco State Government across different policy areas, including waste management, climate change, and air quality.
Guillermo holds a Master’s in Urban Planning from the University of Melbourne and a Bachelor’s in Environmental Engineering from ITESO University (Guadalajara, Mexico).
Gunjan Parik is Director of the Transport programme at C40 Cities. She leads the global transport programme supporting mayors and city governments in delivering climate action.
Her work spans technical policy assistance, peer-to-peer learning, stakeholder and community engagement, and data and research. Gunjan and her team work across critical areas, including public transport expansion and improvement, active mobility, vehicle electrification, and the implementation of Zero Emission Areas. They also collaborate closely with academic institutions, consultants, and data partners to strengthen the evidence base and generate new insights in partnership with cities.
Before joining C40, Gunjan worked at Transport for London (TfL), where she served as Head of Paralympic Transport and Accessibility, ensuring operational readiness for the 2012 Games. She also advised on strategic policy issues as a Senior Associate in the TfL Policy Unit. Previously, she worked in India with PricewaterhouseCoopers as a Senior Consultant across national and local government institutions. Gunjan holds two MSc degrees from the London School of Economics.
Gunjan Parik serves as Director for Transportation at C40. Prior to joining the C40, Gunjan worked at Transport for London (TfL), most recently as the Head of Paralympic Transport and Accessibility, where she was responsible for ensuring TfL capacity to operate a robust transport network able to meet the unique challenges of the 2012 Olympic and Paralympic Games. She also worked as a Senior Associate at the TfL Policy Unit where she served as an advisor on issues of strategic importance for TfL. Previously, Gunjan was based in India where she worked as a Senior Consultant for Pricewaterhouse Coopers, working across a range of government institutions at local and national levels. Gunjan holds an Masters of Science in Management and Regulation of Risk, and an Master’s of Science in Information Systems, both from the London School of Economics.
Hannah Chatterjee manages the C40 Food Systems Network within the Climate Solutions & Networks team. She nurtures relationships with cities across the world who are working on food systems-related climate projects and policies, and helps them share their wisdom and expertise.
Before joining C40, Hannah directed the food policy council in her hometown of Philadelphia, organizing city government officials to be proactive and responsive towards tackling food systems challenges in partnership with residents. She also supports her collective 4DaSoil, which incubates Black & Brown-led food justice projects in Philadelphia. She is deeply committed to promoting cooperative and collective forms of governance, and advancing racial and environmental justice.
She has a BA in History & International Relations from Cornell University, and a MSc in Prosperity, Innovation & Entrepreneurship from UCL.
Hazirah serves as the Senior Manager of Engagement and Partnerships for East, Southeast Asia and Oceania. She is responsible for supporting C40 Vice Chairs in their leadership and assisting mayors across the region to amplify their voices and raise their profile across various platforms. This also includes building stronger partnerships in the region and engaging with various key stakeholders, crucial to member cities’ delivery of their climate action and advocacy priorities.
Hazirah was a city official at Kuala Lumpur City Hall, who assisted Mayors and Executive Directors as Special Officer. She has been highly involved with city networking for Kuala Lumpur City Hall since 2014 and was the focal point for international relations in the Mayor’s Office. Prior to joining C40, she was the Head of the Service Competency Unit, where she provided training and examinations for newly recruited city officials. She has a Bachelor’s Degree in English Language and Literature (majoring in Linguistics) from the International Islamic University Malaysia and a Master’s from the University of Seoul in Urban and Administrative Planning.
Helen leads the technical assistance part of C40’s Air Quality Program and works on deploying projects within cities in the areas of air quality monitoring, health impact assessment, air quality modelling, data analysis and policy development. Prior to this role, Helen led the Empowering Cities with Data Programme to support city governments to a) insitutionalise and transform their data management processes and systems and b) collect criticial data needed to develop and implement targeted policies across all sectors. She joined C40 in 2016 on the Research, Measurement & Planning team and previously worked on climate change, energy and transport policy at the Institute for Public Policy Research (IPPR). She holds an MSc in Environmental Technology from Imperial College London and a BSc in Natural Sciences from University College London.
Hélène Chartier is the Director of Urban Planning and Design at C40. The team she leads develops programmes and activities that support cities to accelerate sustainable and resilient urban planning policies and design practices.
Her team leads the C40 Land Use Planning Network, which supports cities to institutionalise climate action through urban planning regulations; the Reinventing Cities competition, which delivers decarbonised and resilient urban regeneration projects; as well as the Green and Thriving Neighbourhoods programme and C40’s workstream on 15-minute cities.
Hélène previously served as an advisor to the Mayor of Paris Anne Hidalgo. She also worked for the Paris Urbanism Agency and the global consulting firm Arup. Hélène holds a Master’s degree in science and engineering from the École Centrale with a specialisation in building and civil engineering. In the past 15 years, Hélène has lived and worked in Paris, London and New York.
Henrique Goes is C40’s Regional Engagement Manager, LATAM, C40 Cities Finance Facility.
In his previous C40 role, Henrique coordinated the activities of the global clean construction programme, supporting cities around the world to collaborate and drive the transition towards a decarbonised, resilient and socially just built environment.
Before joining C40, he served in the City Government of São Paulo as a director at the Public Innovation Department (011.lab), and was also a policy advisor at the Special Secretariat of Strategic Projects. In both instances, he worked to improve public service delivery in several agendas, such as environment, urban planning, education and health. Earlier on, Henrique worked for Article 19, researching and advocating for government accountability in environmental matters in Latin America. He has also collaborated as a graduate consultant with the Global Fund to Fight AIDS, Tuberculosis and Malaria.
Henrique holds a BSc in International Relations from the University of São Paulo, an MSc in Economic Development Management from the London School of Economics and Political Science (with a focus on just transition and green jobs), and an MSc in Public Management at INSPER (with a focus on social housing and inequalities).
Henry supports the delivery of the Climate Budgeting Programme at C40. He focuses on a variety of topics, including working with cities to advance adaptation efforts and supporting them in their GHG quantification efforts for enhanced measuring and reporting as part of their climate budgets.
Prior to life at C40, Henry worked as a consultant to develop climate action plans with governments of all levels across the world, estimate GHG emissions, and create policies for adaptation measures. He also served at an NGO with a focus on transparency and long-term pathways to reduce GHG emissions with state and regional governments.