Welcome to the abyss.
I'm Jaclyn and today we're explaining how the tides work. Let's dive in.
The consistent ebb and flow of the tides is created by the gravitational
effect of the sun and the moon on the earth.
Just like the earth, all bodies of mass exert a gravitational field, and that field is proportional
to its size.
So the sun being much larger than the moon has a much stronger gravitational force.
However the effect of gravity on another body is also dependent on the distance.
The moon being closer is the dominant impact on the earth and consequentially the tides.
In fact, the gravitational effect of the moon on the earth is approximately twice that of
the sun.
The moon causes the tides because it creates a gravitational differential, this is referred
to as the tidal force.
The moon exerts a gravitational force on the earth, but as I already mentioned this force
is affected by distance.
This means that areas on the earth's surface that are close to the moon experience a greater
gravitational pull than areas that are farther away.
Since the ocean sits on top of the earth, the force it actually feels is the difference
between the gravitational force at the surface of the earth and the force felt at the center
of the earth.
At areas 90 degrees from the moon this differential results in downward force.
Whereas on the side of the earth in line with the moon, the differential results in an outward force.
Overall, this gravitational differential results in an ellipse, with the net force pushing
the water towards the earth-moon line.
The force is very minute.
However, over a large distance, such as the surface of the ocean, this force accumulates
and results in a noticeable difference.
As the earth spins this ellipse of water stays aligned with the moon, so the location of
the two bulges, changes throughout the day.
It is these bulges of water that are the high tides.
And oppositely the low tides are at a 90 degree angle from this.
It takes the earth one day to complete one rotation, so in that time any given place
on the earth experiences each point along the ellipse.
This results in two high tides and two lows tides in the course of a day or tidal cycle.
This is referred to as a semi-diurnal tidal cycle.
If the earth was covered with a hundred percent water then there would be only semi-diurnal tides.
However, the continents can block and affect the tidal patterns.
This can result in diurnal tides, which is just have one high tide and one low tide per
tidal cycle.
There are also as mixed tides which is a mix of semi-diurnal and diurnal tides.
As well as affecting the tidal patterns the continents and geography of the coastline
can also affect the average tidal height.
A tidal cycle is not exactly equal to one day.
The moon also moves around the earth, which results in the tidal cycle last a little bit
longer than a day.
A tidal cycle is 24 hours and 50 minutes long.
This means that each high tide is 50 minutes later than it was the previous day.
Since it takes approximately one month for the moon to orbit around the earth, there
are also monthly patterns in the tidal cycle.
This is when the gravitational effect of the sun is the most noticeable.
When the sun, moon and earth are all aligned, a new moon or full moon are visible.
During these times the gravitational effects of the sun and the moon are additive, creating
the highest high tides and the lowest low tides during the month.
This is referred to as spring tides.
When the sun and moon are at a 90 degree angle from one another relative to the earth their
gravitational forces are in opposition.
Since the moon is the dominant force it will still be aligned with the high tides.
However, the effect of the sun's gravitational force will result in the lowest high tides
and the highest low tides of the month, meaning the tides are less extreme.
This is referred to as neap tides.
Neap tides and spring tides each occur twice in a lunar cycle, with the four quarters of
the moon.
In conclusion it is the movements and gravitational forces of the earth, moon and sun all relative
to one another that causes the tidal patterns.
And that is how the tides work.
I bet it is way more astrophysics than ever expected from me, but if you have any questions
please leave them down below.
As always remember to like and subscribe to see more.
Until next tide I will sea you later.
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