What are spring and neap tides? - NOAA's National Ocean Service
A spring tide—popularly known as a "King Tide"—refers to the 'springing forth' of the tide during new and full moon. A neap tide—seven days after a spring tide—refers to a period of moderate tides when the sun and moon are at right angles to each other.
What is a perigean spring tide? - NOAA's National Ocean Service
These occurrences are often called 'perigean spring tides.' The difference between perigean spring tides and spring tides that occur closer to the moon’s apogee are location dependent and significantly influenced by tidal range, but can be quite large.
Tides and Water Levels - NOAA's National Ocean Service
When the sun, moon, and Earth are in alignment (at the time of the new or full moon), the solar tide has an additive effect on the lunar tide, creating extra-high high tides, and very low, low tides—both commonly called spring tides.
Tides Subject Review - NOAA's National Ocean Service
What is the magnitude of solar tides and how are they expressed? What causes spring tides? What causes neap tides? How many spring and neap tides occur in a lunar month? How are tide-generating forces affected when the moon is closest to the Earth (or perigee)? when the moon is farthest away from the Earth (or apogee)?
Tides and Water Levels - NOAA's National Ocean Service
Tides originate in the oceans and progress toward the coastlines where they appear as the regular rise and fall of the sea surface. When the highest part, or crest of the wave reaches a particular location, high tide occurs; low tide corresponds to the …
What are tides? - NOAA's National Ocean Service
2024年6月16日 · Tides are very long-period waves that move through the ocean in response to the forces exerted by the moon and sun. Tides originate in the ocean and progress toward the coastlines where they appear as the regular rise and fall of the sea surface.
Tides and Water Levels: NOAA's National Ocean Service Education
When the sun, moon, and Earth are in alignment (at the time of the new or full moon), the solar tide has an additive effect on the lunar tide, creating extra-high high tides, and very low, low tides — both commonly called spring tides.
Tides and Water Levels - NOAA's National Ocean Service
High tides occur 12 hours and 25 minutes apart. It takes six hours and 12.5 minutes for the water at the shore to go from high to low, or from low to high. Unlike a 24-hour solar day, a lunar day lasts 24 hours and 50 minutes.
What is a King Tide? - NOAA's National Ocean Service
A King Tide is a popular, non-scientific term people often use to describe exceptionally high tides that occur during a new or full moon.
Tides and Water Levels - NOAA's National Ocean Service
In general, most areas have two high tides and two low tides each day. When the two highs and the two lows are about the same height, the pattern is called a semi-daily or semidiurnal tide. If the high and low tides differ in height, the pattern is called a mixed semidiurnal tide.