Science Concepts—Sea Level

Summary: One consequence of climate change is sea level rise. In order to determine whether global sea level is changing, scientists must be able to understand natural temporal and spatial sea level variability. This topic guide includes resources related to global sea level measurements and trends. Students compare global sea level trends with regional and local sea level measurements using online data and/or through a coastal field experience.

Concepts to teach:

• Crosscutting Concepts
  • Stability and Change
    
• Disciplinary Core Ideas
  • ESS3.D - Global Climate Change
    
• Science Practices
  • Analyzing and interpreting data

Goals:

1. Scientists measure water level to determine patterns and trends.
2. Ocean water levels vary depending on scale and geographic location.
3. Overall, global sea level is rising.

Standards: NGSS Performance Expectations

• HS-ESS3-5 - Analyze geoscience data and the results from global climate models to make an evidence-based forecast of the current rate of global or regional climate change and associated future impacts to Earth systems.

Specific Objectives:
Students will be able to:

1. Define global, local and relative sea level
2. Use online sea level data to determine global and regional trends
3. Use online or collected data to describe water levels for an coastal area in Oregon

Activity Links and Resources:

• Reading: What is sea level? From NOAA Tides and Currents
• Global sea level—Long term changes in global mean sea level is measured by satellite altimetry. View trends from the NOAA/NESDIS/STAR Laboratory for Satellite Altimetry.
• Regional sea level trends—How does the sea level in Oregon compare to other parts of the world?
  • Sea level maps and graphs from NOAA Tides and Currents
  • Sea level changes along the Oregon coast tend to be LOWER than the world average. This is because the Juan de Fuca plate is subducted beneath and is pushing up the North American Plate. Video: Sea-Level Rise for the Coasts of California, Oregon and Washington - NAS
• Local Sea Level is measured by tide stations, which refer to the height of the water as measured along the coast relative to a specific point on land. Invite students to explore online water level data.
  • Review: OCEP Tides of the Estuary
  • Real time CO-OPS Station water level data
• Visit a coastal or aquatic site to determine current and historic high water level based on:
  • available data sets (local, online, etc.)
  • historical photos (contact the local historical society)
  • landscape indicators (identifying plant communities, erosion effects, etc.)
  • proximity of human infrastructure
  • direct measure with a meter stick, repeat measurements over time if possible

Assessment:

• What happened to the water level as the temperature increased?
• What caused the water level in the flask to change over time?
• Would salt water react the same way as fresh water? How could you design an experiment that would test your hypothesis?