Sea level rise:
an existential threat?

 

How global cooperation can address rising seas and build a more resilient and sustainable future

Open-pit mine viewed from above

Why is the UN discussing sea level rise?

Every coastal city.

Every small island.

Every river delta.

They are all facing a future shaped by rising seas.

As the planet warms, the ocean is expanding and glaciers and ice sheets are melting, pushing sea levels higher.

Sea level rise is now accelerating at an unprecedented level, reshaping coastlines and increasing risks for islands, coastal cities, river deltas and Arctic communities.

Nearly 900 million people live in low-lying coastal zones, and more than 1 billion could be exposed by 2050.

For small island developing States and low-lying coastal countries, rising seas threaten land, livelihoods and even statehood.

At the United Nations, Member States are asking a fundamental question:

How can the world protect people, cultures and nations from rising seas?


  Secretary-General's report:  Challenges related to sea level rise and ways to address it


Why is sea level rise an urgent call to action?

A young climate activist from Tuvalu and a NASA scientist urge Member States to respond now, as rising seas threaten communities, cultures and futures.

Did you know?

 

Sea level rise is no longer a future threat. It is already affecting communities, ecosystems, and the future of low-lying communities and States.

Sea level rise is speeding up.

  

The rate of global mean sea level rise in 2014–2023 was more than twice the rate recorded in the first decade of satellite measurements, 1993–2002.

Up to 1.2 billion people could be displaced

   

By 2050, sea level rise and related climate impacts could contribute to the displacement of up to 1.2 billion people globally, placing growing pressure on communities, infrastructure and resources.

Rising seas can make freshwater salty

  

Sea level rise can push saltwater into freshwater sources, affecting drinking water, agriculture and health.

Sea levels could rise by up to 30 centimetres by 2050

  

Global sea levels are expected to rise by 15 to 30 centimetres by 2050, on average, according to estimates cited from the Intergovernmental Panel on Climate Change (IPCC).

Sea level rise raises legal questions

  

Sea level rise is raising legal questions about maritime zones, statehood and people affected by rising seas. The International Law Commission has explored these issues in international law.

Small island developing States face special risks

  

Many small island developing States have limited land, high exposure to coastal hazards and scarce freshwater resources, making sea level rise one of their most serious threats.

Rising seas are sinking futures. They endanger coastlines, livelihoods…the very existence of States themselves.”

ANTÓNIO GUTERRES, United Nations Secretary-General
Portrait of the Secretary General, António Guterres

How has the UN responded to sea level rise?

 

Sea level rise has been on the United Nations agenda for decades. Here are some of the key milestones in international action.

1989
General Assembly first addresses sea level rise directly
2014
SAMOA Pathway highlights risks facing small island developing States
2024
Antigua and Barbuda Agenda strengthens action for small island developing States
2024
General Assembly holds its first high-level meeting on sea level rise
2025
International Law Commission advances legal work on sea level rise
2026
General Assembly to return to sea level rise at the high level

Five questions

 

Looking for a quick overview? Start with these five key questions on sea level rise.

The UN supports countries facing sea level rise through climate action, adaptation, early warning systems and international cooperation.

It also helps mobilize financing and strengthen resilience in small island developing States and other vulnerable countries, while supporting global efforts under the Paris Agreement to limit future sea level rise.

The 24 September meeting aims to galvanize action on rising seas by bringing together leaders, experts and other stakeholders.

It is expected to strengthen cooperation, advance practical solutions and support vulnerable communities, particularly in small island developing States and low-lying coastal areas.

Small island developing States are on the frontlines of sea level rise.

Rising seas threaten homes, freshwater, food security, livelihoods and cultural heritage, while limited resources and high exposure to climate shocks make adaptation especially challenging.

As seas rise, complex legal questions are emerging around maritime boundaries, statehood and the rights of affected people.

These issues are a focus of ongoing work by the International Law Commission.

Sea level rise threatens not only homes and infrastructure, but also cultural heritage, traditional livelihoods and community identity.

For many small island developing States and coastal communities, protecting culture is a vital part of adapting to rising seas.

Dive deeper

 

Explore expert insights, stories, and resources on one of the defining challenges of our changing climate.

More from the United Nations

 

Explore the latest news and updates from across the United Nations on sea level rise.