IGCSE Marine science section 1.1 :Structure of the Earth

Welcome to section 1.1 in the syllbus, and chapter 1.1 in the IGCSE coursebook.

Index can be found here

The syllabus here decides the stuff we need to work on.

1: Describe the Earth as a planet orbiting the Sun, and the Moon as a natural satellite orbiting the Earth

2 State that gravity keeps the Earth in orbit  around the Sun, and the Moon in orbit around the Earth

3 Describe the structure of the Earth 

4 State that the iron core creates a magnetic field around the Earth

You can find the keywords for the chapter here:

So,the chapter covers the structure og out wonderful planet ,and it's location in the solar system. This might seem like a funny way to start marine Science, but the location, rotation and tilt of our planet have a huge impact on our marne systems. Just a bit closer to the sun, and most water vould be vapor. And just a bit further away, and most water would be ice.

Earths tilt also explains our seasons, and seasonal variations in light intensty and temperature, both are hugly important for understanding marine systems in othe reetions than the tropics.

This also helps explain why both the artic and antarctic regions can have ice covers.

Our Moon is a natural sattelite, and it have a huge effect on our marine system with tides due to gravity, (more in section 1.4)

The earth takes 365 days (one year) for a trip around the sun. The Moon orbiting earth and earth spinning on its own axis give us the lunar cycle and the day and night cycle

Earth is, together with Mercury, Venus and Mars what we call rocky planets (opposed to Saturn and Jupiter who is mainly gas) but the rock is only solid in the outher parts.

Earth have a molten layer of rock (the mantle) and a outher core made of molten metal. 

Again, this might seem like a fun way to start marine science, but the magntic field created by the metallic core have a huge impact on life and navigation, and the shifting currents of the mantle leads to the ever changing surface of our planet (Described in secton 1.2) as new seabed is created, volcanos erupt and new islands rise due to the activity of the lava  in the mantle.

So, our position in the solar system, the fact that we have a huge and stable moon, the magnetic field created by the iron inside our planet and the ever shiting tectonic plates drifting on top of the mantle creates the system in where our oceans exist.

Welcome to the wonderful world of IGCSE Marine science.

Here is a bit more detailed video on our wondeful planet, that 3 rock from the sun where everything happens.

A good video about seasons: