This week, I am honoured to join about 20 of my fellow Young Global Leaders as we embark on the Greenland Learning Journey with the World Economic Forum. I am incredibly excited to make my first visit to this intriguing and beautiful island - the largest in the world. But I am also keenly aware that our expedition will bring us close to the alarming realities unfolding at the epicentre of global climate change.

In preparation for this journey, I have thought about connections between Greenland, with its population of 57,000, and New York City, whose 8.6 million residents I serve as Commissioner for International Affairs. Both destinations stir the imaginations of travellers. Now the challenge of climate change links us, as we share the responsibility of ensuring a safe, liveable planet for future generations.

As our planet warms and the melting of the vast Greenland ice sheet accelerates, effects such as rising sea levels and altered weather patterns can be felt on coastlines and in communities thousands of miles away. For many New Yorkers, the devastation of Superstorm Sandy in 2012 served as a wake-up call. It marked a turning point in our recognition of the profound dangers posed by climate change, particularly for cities on the frontlines of the battle.

I am grateful for the opportunity to speak to my fellow Young Global Leaders from business, technology, academia and other fields about influential steps that city governments are uniquely positioned to take on climate change. With more than half the world’s population now living in cities - a proportion projected to reach two thirds by 2050 - this conversation must include the voice and perspective of cities.

To tackle climate change, we need city diplomacy. City diplomacy entails local governments actively engaging with the international community by leveraging the global connections and unique resources of cities. Based on the shared values of inclusion, partnership and cooperation, city diplomacy involves exchanging best practices with partners around the world, and leading on global challenges, particularly at a time when some national governments appear to be retreating.

New York City is home to the largest diplomatic community in the world - the permanent headquarters of the United Nations (UN), 193 Permanent Missions to the UN, 115 consulates, and more than 70 trade missions. Our residents across five boroughs, more than half of whom are immigrants or the children of immigrants, speak 800 languages. The global engagement of city diplomacy is a natural expression of serving our constituents, including our urgent work on climate change.

The importance of city engagement on climate was underscored last June when President Trump announced that the US would withdraw from the landmark Paris Agreement. New York City Mayor Bill de Blasio and hundreds of other mayors across our country responded by affirming that their cities would remain in the global agreement, and step up their efforts to fight climate change on the local level. Mayor de Blasio issued an executive order to honour the Paris Agreement goals, and the resulting 1.5°C plan is the first-ever Paris Agreement-compliant action plan for a city.

Our Paris alignment strategy calls for enhanced communication to educate New Yorkers on what they can do for the climate as local citizens. As part of this effort, the Mayor’s Office for International Affairs creatively taps our resources and position to reach and engage new audiences around climate action, including affected communities who might not otherwise have an opportunity to participate in the conversation. We do this in particular through our two flagship programs, Global Vision | Urban Action and NYC Junior Ambassadors.

In April 2015, Mayor de Blasio launched OneNYC, our administration’s groundbreaking strategic plan for sustainable and inclusive growth. OneNYC provides a blueprint for achieving goals such as lifting 800,000 New Yorkers out of poverty, expanding access to nutritious and affordable food, and ensuring that those threatened by climate change - often the most vulnerable New Yorkers - are protected.

Five months later, in September 2015, world leaders at the UN committed to the Sustainable Development Goals (SDGs) to end extreme poverty, fight inequality and injustice, and prevent the harmful effects of climate change by 2030. Our Global Vision | Urban Action programme showcases the synergies between the OneNYC plan and the SDGs, and how our partners at NYC agencies are translating the SDGs through their work on water, sanitation, mental health, decent employment, and so much more on the local level.

In May, we took a significant step forward with the announcement that New York City will become the first in the world to report directly to the UN about our local progress toward the SDGs, with the launch of our Voluntary Local Review in summer 2018. By championing the SDGs among our local constituents and colleagues, we are connecting the most populous city in the US to the shared language of this global conversation. We hope to inspire other cities to implement the SDGs and track their commitments.

Youth engagement also sits at the heart of our work around climate action. Our NYC Junior Ambassadors programme connects seventh-graders throughout the five boroughs with the work of the UN. It uses the lens of the SDGs to empower students to take action on global issues, starting locally in their own neighbourhoods. Since 2015, the NYC Junior Ambassadors programme has reached more than 1,000 students and educators in more than 50 classrooms, many of whom have completed projects on climate and its intersection with challenges including gender equity and the refugee crisis.

The world today has the largest population of young people in history - 1.8 billion. Technology makes them more connected than ever. They stand to suffer the most from the increasing effects of climate change, and they are particularly motivated by it. The NYC Junior Ambassadors programme is giving students the tools to organize their own climate advocacy and exercise global leadership, including opportunities to speak at the UN about the need to protect our oceans and reduce our carbon footprint through sustainable consumption.

Cities hold enormous potential to influence the global conversation and agenda on climate change. I am pleased to share just some of the ways we are approaching this in New York City. We can do even more, especially when we embrace city diplomacy.