From New York to Nice: Mayors of Coastal Cities and the International Community Mobilise to Address Sea Level Rise

On Wednesday, September 25, 2024, the 79th United Nations General Assembly (UNGA) in New York hosted for the first-ever a high-level plenary session focused on the challenges of sea level rise. During this meeting, the Global Center for Climate Mobility, formally announced its support to the launch of the forthcoming Ocean Rise & Coastal Resilience Coalition of Cities and Regions. This initiative strikes a chord in Nice, where 18 mayors of coastal cities signed the Sea’ties Declaration of the Ocean & Climate Platform, calling for increased international support to adapt to sea level rise. The Coalition, presided by the Mayor of Nice, Christian Estrosi, will be officially launched at the third United Nations Ocean Conference (UNOC3), co-organised by France and Costa Rica, marking a major milestone of these global efforts. 

From New York to Nice, an unprecedented mobilisation to address the existential threats of sea level rise to coastal cities and regions

In New York, this crucial meeting marks the first time a high-level plenary has been dedicated to the  existential threat posed by sea level rise. By elevating this issue at the top of the global agenda, the international community reaffirms its commitment to strengthening multilateralism and cooperation to provide concrete solutions for coastal states and communities facing the immediate impacts of rising seas.

To support this momentum, the Global Center for Climate Mobility, a UN-backed international partnership focused on climate mobility, announced at its annual summit its full support and participation in the governance of the upcoming “Ocean Rise & Coastal Resilience” Coalition which is chaired by the city of Nice, with the support of France and Costa Rica as co-hosts of UNOC3, and whose preliminary coordination has been entrusted to the Ocean & Climate Platform. 

This international mobilisation resonates in Nice, where, at the Nice Climate Summit, 18 mayors signed the Sea’ties Declaration. Launched by the Ocean & Climate Platform at the One Ocean Summit in 2022, the Declaration calls for accelerated international support for the adaptation of cities at the forefront of the fight against sea level rise. Today, it brings together 70 mayors and governors of coastal cities and regions worldwide, such as New Orleans, Nice, Lagos, and Auckland. 

From New York to Nice, the announcement of this new partnership with the Global Center for Climate Mobility, along with the increased engagement of mayors of coastal cities, marks a key milestone in the formation of the Coalition set to launch at the third United Nations Ocean Conference in June 2025 in Nice, France. As Gina Guillen Grillo, Special Envoy of the President of Costa Rica for the Ocean, remarked, this will be a landmark step toward “ensuring a future where the only thing rising higher than the ocean is our determination to protect our planet.”

A Coalition to collectively support the adaptation of coastal cities and regions

Aiming to bring together hundreds of elected officials from coastal cities and regions worldwide, representing one billion people directly threatened by sea level rise by 2050, the Coalition of Cities and Regions “embodies our collective commitment to confront this crisis head-on,” stressed Loreley Picourt, Executive Director of the Ocean & Climate Platform. 

At the One Planet Polar Summit in November 2023, French President Emmanuel Macron entrusted the Mayor of Nice, Christian Estrosi, with the mandate to lead this future Coalition, and the Ocean & Climate Platform to coordinate its development. Christian Estrosi clarifies “first, it will ensure that their interests are represented on the international stage, where their voices are too often marginalised. Second, in light of the urgent need to better understand the risks and vulnerabilities they face, the Coalition will foster enhanced scientific cooperation to inform local decision-making. Finally, recognising that local authorities cannot bear the financial burden of adaptation alone, it will mobilise key actors in the finance sector to help meet these pressing challenges.”

In Nice 2025, a global event and an initial action framework for coastal cities and regions

In June 2025, the third United Nations Ocean Conference will be organised in Nice, where the adaptation of urban coastal areas will be a central issue. A special day, on June 7, will be dedicated to this topic, officially launching the “Ocean Rise & Coastal Resilience” Coalition. This will be a decisive moment to “ensure that our coastal cities and regions remain vibrant hubs of life, culture, nature, and well-being”, emphasised Olivier Poivre d’Arvor, Special Envoy of the French President for the United Nations Ocean Conference and Ambassador for the Poles and the Ocean.

Credits: ©Ville de Nice / David Nouy

Contacts:

  • Théophile Bongarts, Head of Coastal Adaptation, Ocean & Climate Platform: tbongarts@ocean-climate.org
  • Sarah Palazot, Project Officer Sea’ties Initiative and communication, Ocean & Climate Platform: spalazot@ocean-climate.org