Tides Flashcards
(17 cards)
What are tides?
The daily rise and fall of sea levels at specific locations.
What is the primary cause of tides?
Moon’s gravity pulls on Earth’s water, creating tides.
What is the secondary cause of tides?
Sun’s gravity also contributes to tides but has a smaller effect.
Where do the two high tides occur due to the Moon’s gravitational pull?
- Under the Moon: Where the Moon’s gravity is strongest.
- Opposite Side of Earth: Where the Moon’s pull is weakest.
How long does it take for the Moon to revolve around Earth?
24 hours and 50 minutes.
How often do high tides occur?
Every 12 hours and 25 minutes.
What is the time between a high tide and the next low tide?
~6 hours and 12 minutes.
What is the effect of the Sun on tides?
Sun’s gravity pulls Earth’s water and causes additional, smaller tides.
What local factors can affect tidal patterns?
- Shape of the coastline.
- Geography of the area.
What is the tidal range?
The difference in ocean level between high tide and low tide.
What factors affect the tidal range?
- Seafloor Slope: Gentle Slope results in greater distance movement, Steep Slope limits movement.
How do tides behave like waves?
Their effects can be additive depending on the alignment of the Sun and Moon.
What are spring tides?
Occur when the Sun and Moon are aligned, creating higher high tides and lower low tides.
When do spring tides occur?
Approximately every 14 days.
What is misleading about the name ‘spring tides’?
Not related to the spring season.
What are neap tides?
Occur when the Earth, Moon, and Sun form a 90° angle, resulting in the smallest tidal range.
When do neap tides occur?
Halfway between spring tides.
