Why is water level important?
Not only is accurate tidal data crucial for maritime navigation, but tides and water levels is critically important across multiple sectors, including public safety, environmental protection, and infrastructure planning.
- Flood prediction: Real-time monitoring helps predict, issue warnings and implement safety measures for local residents and emergency responders.
- Climate change and sea level rise (or just ‘coastal erosion’): Records of accurate water levels contribute to understanding and documenting sea level rise and coastal erosion.
- Coastal and environmental management: Coastal ecosystems, such as marshes, tidal flats, estuaries, and kelp forests, depend on tidal patterns. Monitoring changes in water level can be studied in relation to environmental stress or habitat loss.
Understanding Water Level and Tides
Water levels are the actual height of the sea or ocean surface at any given time. They can be influenced by tides, weather, river flow, and long-term sea level changes.
Tides are the regular, predictable rise and fall of the ocean water levels, primarily caused by the gravitational pull of the moon and sun.
Tides are the rise and fall of the ocean that are predictable patterns, while water level is the actual height of the water surface that is due to the tides, along with wind, barometric pressure and local currents.
Why is Water Level of Interest to Alaska?
Alaska’s coastal communities – many are low-lying and remote. Vulnerable to coastal flooding.
Support for subsistence and commercial fishing – fish movement, boat access to harvesting areas, timing of safe travel. Protect livelihoods.
What is a datum and why is it important?
Let’s use the example of two stick figures who want to know if they’re the same height.
Person A says they’re the same height as Person B.
Is this correct?
It depends on the datum!
Let’s say our datum is the floor. Since the datum is the floor, the measurements will start at the floor and go up to the measuring point, which is the tops of their heads.
Measuring from the floor (datum) to the top of their heads, Person A is the same height as Person B.
The more conventional way of measuring height is to set the datum as the feet.
Now measuring from the feet to head of each person, we see that they are different heights.
This is why it’s important to understand what datum is used for data measurements and how it affects the outcomes.
