What is Sea Level

The video explores the complexities of measuring sea level due to Earth's non-uniform shape and varying gravitational forces. It explains how the Earth's rotation causes bulging at the equator, affecting sea level measurements. The gravitational pull of landmasses and varying densities within the Earth further complicate this. Geodetic scientists use the Earth Gravitational Model to accurately define sea level, accounting for these factors, and integrate this model into GPS technology for precise location data.

Why is it difficult to define sea level on Earth?

• Because the Earth is perfectly spherical.

• Due to the Earth's flat shape.

• Because the Earth is neither flat nor perfectly spherical.

• Because the Earth is a perfect cube.

What causes the Earth's equator to bulge?

• The Earth's rotation.

• The Earth's magnetic field.

• The Earth's atmospheric pressure.

• The Earth's gravitational pull.

How does the Earth's varying density affect sea level?

• It causes uniform sea levels everywhere.

• It makes the sea level higher at the poles.

• It has no effect on sea level.

• It causes sea levels to vary due to different gravitational strengths.

What role do continents play in sea level variation?

• They make the sea level uniform across the globe.

• They repel water, lowering sea levels nearby.

• They attract more water due to their mass, raising sea levels nearby.

• They have no effect on sea level.

What is the Earth Gravitational Model used for?

• To predict weather patterns.

• To measure the Earth's temperature.

• To accurately predict sea level and assist in GPS systems.

• To calculate the Earth's magnetic field.