[MUSIC] The first local engine of the weather is the orography. What is orography? Something as simple as the presence of a anything that will obstruct the direction of the wind. If we have a wind approaching a mountain, Basically the wind would have to either ascend it or surround it. And that will generate changes in the direction of the wind, evidently, and in its intensity. There are two factors that are important to understand. And they are related to the strength of Coriolis. They are called backing and veering. What is backing and veering? Let's use the left hand. Look at the law of Buys Ballot, the storms are to my left if I turn my back on the wind. In the Northern Hemisphere, if the speed increases, what will I get? Veering. It means that the wind, by the force of Coriolis, by that vector we have said that is multiplied by its angular velocity, stronger the wind, the farther to the right, This is the veering, the wind will do so when the speed increases. If you slow down the speed will go to the other side, this is the backing. Keep in mind that veering goes clockwise, and backing, anti-clockwise direction. And that when we have a wind that is disturbed by the presence of the territory. Of the orography. Let's see that it has a very marked change in direction speed. Look, let's see, for example, a couple of situations, in which the wind is parallel to ground. If this is the ground, this is the land, and we have a wind. Yes. Notice that I have a wind here, which is a strong wind. But as we get closer to the ground, as we approach ground. The wind, by the effect of friction, is going to lose intensity. It will lose strength. If we remember what we said before, the veering and the backing, look, this wind from here, as it is faster, it tends to go this way. But this, as it is weaker, will have a tendency to make its backing, to do in the other direction. So, here, what we are going to see is that there will be a tendency of this wind to do backing. As it is slower, as is a less strong wind, it goes to your left and therefore you will see than the current lines would be how the air would move parallel to the coast, would be lines like that [SOUND]. Notice what happened to us. That there is a confluence of the air and then when we speak of convergence and divergence. We will see that in this area here, typically with winds parallel to the coast, it will form cloudiness and even if it is an air that is very humid, there may be showers or precipitation with winds from the west. For example, on the coast of the Bay of Biscay. Typically in front of the entire Cantabrian coast, a line of showers is formed. As consequence of this backing, consequence of the presence of this separation between sea and land. Another of the typical situations [SOUND] that can occur, [SOUND] it would be wind that enters towards the coast. Note that if here I have a wind as it approaches the coast, this wind is going to lose strength. And here it will be less strong. Because of the friction from the presence of the land. Even here there may be mountains, here the wind will stop. What is going to happen? If the wind is slower, it again goes to your left, it is backing. So here's what we're going to see. Goes left. This one also a little bit compared to it. The power lines will give us some variation of the wind to your left. So if you do a regatta, or if you are sailing near the coast with winds perpendicular to the coast. and you have a buoy they put here, you will know that when you are closer to shore, the wind will be tilted. You have to work in this tactical direction. So this is going to happen in all wind zones parallel to the coast. Let us now see the case of the Straits. You will see that it reflects the effect of veering. What is a strait? Well, it's an area, look. An area where the wind will be forced to pass through a channeled place, there will be an increase in wind speed. If we are here, imagine that we are in a situation of west in the Strait of Gibraltar. We have a wind, this amount of air will have to pass through this narrower area. And there is going to be an increase in wind speed. Here the vector of the wind is going to be much larger than before we reach the strait. By effect of the territory, of the land. Here maybe, not so much the speed of the wind, the part of the axis is where there will be a wind perhaps stronger. We will see that it is not exactly like this, now you will see the reason why. There is less wind here, there is a lot more wind here, and this is veering. Why? Look, because if the wind is strong, what does the wind do? It goes to its right, the wind is going towards this side. Therefore, we will notice when we are entering in a channel area, in a narrow zone. Let me see if this writes... That the wind is going to your left. And this, look, we will notice it when we are approaching a narrow zone. In that power lines They will be like this [SOUND]. Notice that here I will have a wet advection. And typically, at the entrances of the channels or the areas of strait, we will see that here will be cloudiness, due to the effect of the veering associated to the increase of the wind speed when crossing a strait. I leave you a question now, we have seen this with a westerly... Crossing the Strait of Gibraltar, but perhaps the most typical and classic wind-strong sensation, in the Strait of Gibraltar, would be that of the uprising of the wind in the opposite sense. Let's see a question... Where will you see the cloudiness in rising situations in the Strait of Gibraltar?. We'll respond in the next video.
