What is Sea Level Rise?

Sea level is the average level between high tide and low tide where the surface of the sea meets a shoreline. Sea level rise describes an increase in this average level.

Around the globe, average sea level rose throughout the twentieth century, and the rate of rising has accelerated in recent years. Worldwide, sea level rise directly threatens the lives and livelihoods of 2 out of every 5 people.

Changes in sea level occur naturally in response to expanding oceans and continental uplift or sink. Today, two factors contribute most significantly to dangerous sea level rise: warming ocean water and melting ice sheets. Both factors result from rising global temperatures and climate change.


Sea Level Rise

  • Erodes shorelines and contributes to coastal flooding
  • Inundates low-lying wetlands and dry land
  • Increases the flow of saltwater into estuaries and groundwater, which contaminates water supplies for drinking and agriculture
  • Makes coastal infrastructure more vulnerable to damage from storms