Tidal range describes how much the sea level changes between high tide and low tide. It varies with the positions of the Moon and Sun, the timing of the lunar cycle, local geography, and sometimes weather. Understanding tidal range helps explain coastal flooding risks, differences between coastlines, and how tidal environments are classified.
Tidal range is the difference in height between high tide and low tide. Tides are the rise and fall of sea levels associated with gravitational forces from the Moon and Sun, Earth's rotation, and centrifugal force related to the Earth-Moon system.
All flashcards
What is tidal range?
Tidal range is the height difference between high tide and low tide.
How is mean tidal range calculated?
Subtract mean low water, the average low-tide level, from mean high water, the average high-tide level.
What causes spring tides, and when do they occur?
Spring tides occur around new and full moons, when the Moon and Sun are aligned with Earth and their gravitational effects reinforce one another. They have a larger tidal range.
What is an amphidromic point?
It is a point within a tidal system where the tidal range is almost zero.
What are the main tidal-range classifications?
Micro-tidal is below 2 metres, meso-tidal is 2–4 metres, and macro-tidal is above 4 metres. Some systems above 6 metres are also described as hypertidal.
Quiz questions
What does tidal range measure?Answer: The height difference between high tide and low tide.
Which lunar phase and alignment are associated with spring tides?Answer: New or full moon, with the Moon and Sun aligned relative to Earth.
Why is the tidal range smaller during a neap tide?Answer: The Moon's and Sun's force vectors act at roughly right angles, partly counteracting one another.
A coastal location has a tidal range of 3 metres. How is it classified?Answer: Meso-tidal.
Which conditions can raise water levels and increase tidal range beyond astronomical predictions?Answer: Sustained storm-force winds in one direction combined with low barometric pressure.
Based on the Wikipedia article Tidal range, licensed CC BY-SA 4.0. Adapted into a summary, flashcards and quizzes.