[MUSIC] In this module, we are going to talk about the Global Ocean. But the Global Ocean is a very huge space of water on our planet. So let's go to our planet which is called the Earth, which is our land. Our land is the Earth and at a first sight, our land is something like this. So we have landscapes, as several kind of landscapes, but the real Earth is this. This is almost all water. There's water in the ocean, there's water in the atmosphere, in a form of clouds. And this is the object of this first lecture is: what happens with the water on the Earth. How much water is and where? This is a big amount of water is in the oceans. Here are the numbers, you can just see, this numbers. I'm not going to talk about this because you find this numbers in a lot of places. But to have an idea of this volume, these numbers that you have seen. It's better if you see this proportional issue. If the oceans were a swimming pool, then, the continental ice which is the next component of water that have more volume, is a bath, the underground water, water which is below the earth, below the land is about a bucket. All the whole water of rivers and lakes on land is about a very, very small piece of water, they protect this small bucket. This protection of a finger, and the water in the atmosphere is just a drop of water, in this proportion, to have an idea. But water is moving from one component to another is not always even. See the atmosphere flowing, underground water flowing, rivers and finally to the sea. That moving from one component to other is the water cycle and we are just giving some figures about the water cycle. The water cycle, the naif version of the water cycle is like this. So you can imagine that it's, but this is a vision from land. The real vision of the water cycle, you have to see from the ocean which is the most, covers the Earth. And here is a section, it's a virtual section from the North Pole to the South Pole. And we can see that in the North Pole there is no land. It's an ice cover because the surface of the ocean is covered by ice. Here, these is also ice covered. But also an ice cover above the land. This is the Antarctic, and this is the ocean. So you can see that the ocean is evaporating. That's these waters evaporating here, it's condensing in clouds and then precipitating. Most of the water precipitates in the ocean. And this is the real, the real. This is a scheme of the amount of water moving from ocean to continents, from ocean to atmosphere, from continents to the ocean. From continents to the atmosphere, and finally from the atmosphere to the ocean, and from the atmosphere to the continents. And just to have an idea this is the proportion, so only about 20 to 22% of the water is raining,let's say from the atmosphere. Is raining on the continents while the 78% is raining into the ocean. And here are some fields that we will discuss later. Just that here, the only thing is that, if you see the water raining on the continent, 63% of the water raining from the continent is recycled. The water evaporating from the same continent, just moving from the plants or from the rivers or from the lakes to the atmosphere. And it's safe fresh water just flowing from the surface to the upper atmosphere. While 37% is new fresh water or is water coming from the ocean. It's evaporated from the ocean so it's from salty water. That's the difference. And this is an important difference because this is, let's say, some kind of desalinization of the water. And this is the new fresh water. And now in the next chapter we will see how? Where? And when? This fresh water is coming. And this will give us an idea because this is one of the first agents, moving water of the oceans.
