Science & Policies

Sea Level 101

Are you interested in Sea Level Rise? Here are some resources:

Link to U.S. Sea Level Change

“This site provides federally supported data visualizations coupled with explanations and science education to help communities prepare for challenges that will affect our coastal environments. By showing how sea levels are changing regionally, the site provides a foundation to inform decision-making related to coastal planning, resource management, and emergency operations.”

Source for information on:

  • Global Sea Level Rise
  • Local Sea Level Change
  • How Measurements are Taken
  • Impacts
  • Future Sea Level
  • What Can We Do?

Sea Level Rise in California

Interested in information on California Policy, Sea Level Rise Scenarios, and Impacts?

Link to California Sea Level Rise Guidance (Science and Policy, 2024)

A background range of five scenarios for sea level rise. Rise in sea level is dependent on the level of future emissions and measured in meters. California recommends focusing on the intermediate through high scenarios. These scenarios consider high emissions, higher warming, and rapid ice sheet loss. Scenarios for the North Spit of Humboldt Bay also include rise in sea levels due to local rates of vertical land motion.

Table of Contents:

  • Executive Summary
    • Why Are We Updating the Guidance
    • Statewide Averages for Five California Sea Level Scenarios
    • Key Takeaways
  • 1 . Introduction
    • 1.1. Existing State Policy Guidance and Sea Level Rise Planning
    • 1.2. Purpose & Intended Use
    • 1.3. How This Report was Developed
    • 1.4. Updating the Science Foundation for Statewide Policy Guidance
    • 1.5. Translating Science Into Policy Guidance
  • 2 . California Sea Level Scenarios
    • 2.1. Updated Scientific Understanding
    • 2.2. Steps to Build California Sea Level Scenarios
    • 2.3. Sea Level Scenarios 2020-2150
    • 2.4. Sea Level Scenario Storylines
  • 3 . Combined Impact of Sea Level Rise and Other Coastal Hazards
    • 3.1. Flooding and Sea Level Rise
    • 3.2. Groundwater and Sea Level Rise
    • 3.3. Coastal and Shoreline Erosion
    • 3.4. Preparing for Extreme Coastal Storms
  • 4 . California Sea Level Rise Policy Guidance
    • 4.1. Summary
    • 4.2. Stepwise Process to Apply Sea Level Scenarios in Planning and Projects
    • 4.3. General recommendations for Sea level Rise Planning and Adaptation

California Coastal Commission Policy Guidance

Interested in more information on policy guidance?

Link to Sea Level Rise Adopted Policy Guidance

This document provides interpretive guidelines for addressing sea level rise in local coastal program and coastal development permits incorporating best science principles, environmental justice, and more.

Available Sections:

  1. Introduction
  2. Principles for Addressing Sea Level Rise in the Coastal Zone
  3. Sea Level Rise Science
  4. Consequences of Sea Level Rise for Communities, Coastal Resources, and Development
  5. Addressing Sea Level Rise in Local Coastal Programs
  6. Addressing Sea Level Rise in Coastal Development Permits
  7. Adaptation Strategies
  8. Legal Context of Adaptation Planning
  9. Additional CCC Efforts to Address SLR