Answer:
A <em>mixed semi-diurnal</em> tidal pattern has two high and two low tides of unequal heights during each lunar day.
A <em>diurnal</em> tidal pattern has one high and one low tide during each lunar day.
A <em>semi-diurnal</em> tidal pattern has two high and two low tides of approximately equal heights during each lunar day.
Explanation:
Mixed semi-diurnal pattern:
A mixed semi-diurnal tide cycle has four tides each lunar day. This cycle manifests as a succession of two high and two low tides, both of which are <u>different in size.</u>
<em>Diurnal inequality</em> is a term that refers to the <u>difference in height</u> between two high/low tides.
A region that is frequently affected by semi-diurnal tide cycles is the West Coast of the United States.
Diurnal pattern:
On the other hand, a diurnal tide cycle only has two tides each lunar day – one high tide and one low tide, although for a <u>long period</u>. <em>The tidal period</em>, which is the period <u>from one high (or low) tide to the next</u>, during the diurnal cycle, is 24 hours and 50 minutes – an entire lunar day! This is why we call it the diurnal tide cycle.
This tide pattern is experienced in the areas of the Gulf of Mexico.
Semi-diurnal pattern:
Were there only water on Earth, this would be the only existing pattern.
During the semi-diurnal tide cycle, affected regions experience four tides every lunar day: two high tides and two low tides, of approximately <u>equal size</u>. The tidal period is in this case 12 hours and 25 minutes: half of a lunar day, which is exactly why we call it a semi'diurnal tide cycle!.
This is the most frequent tidal pattern among the world’s coasts.
