[MUSIC] In the next subject, we'll talk about the South Pacific South Pacific you can see here. It officially starts at New Zealand, although you could argue that this is part of it, and ends at Cape Horn, the tip of South America. System based on the global climatology is again the high pressures on mid latitude. High pressure here. There's high pressure over here. This one is a little bit too far south, but there's here. All right, and here you can see the various low pressure systems of the southern ocean. There's one over here. All right. And again, all this westerly, south-westerly, westerly, north-westerly flow. All the pressure to the south. What you want to keep an eye on here in the south Pacific, apart from the ice coast we have to deal with. Always this conflict when we want to go further south. We want to find more wind. More favorable winds on average. We don't want to go north because there's west wind and we have to keep an eye on cyclogenesis. Cyclogenesis in the Pacific can happen out of a few things. One of those little tropical systems like we have over here could wiggle its way down and somehow get regenerated. Always something to keep an eye on. But the main system really is if there are two high pressure systems on the Pacific, one feeding in cold air from the Arctic, one feeding down warm air from the tropics, southeasterly trace over here. This is an area where a low pressure can form, and it's something the competitors will be watching out for to see if that's going to happen in the predictions they have on board in the grip files and all that and then to make the best use out of that as far as the strategies are concerned. We have spoken in the subject about the South Indian low [INAUDIBLE] about in the South Pacific subject About tropical systems getting regenerated or coming down into the main Southern Ocean flow. Here's an example of the tracks of all tropical cyclones, hurricanes, typhoons, whatever they're called in the various parts of the world, right? And here you can see that to the east of New Zealand, occasionally something dribbles down into the Southern Ocean. There's one here coming all the way down here. One coming down here. One coming down here. We're going back to the Indian. Madagascar over here. You can see that here it's a little bit more frequent, right. Whereas in the North Pacific and in North Atlantic, it is very frequent. So unlikely but be ready for the unexpected. So here we are, back in the South Pacific. First boats have reached Cook's Strait. First boat is coming out of now. Some boat actually stopped here to do repairs, which was allowed in the last race. The ice gates. Strong winds down to the south. High pressure's blocking the mid-latitudes. Again the same game and all the devil will be in the detail, you can see here now there is high pressure situated to the east and south east of New Zealand, which is slowing down the leading boats. They want to get here, but at the moment there's a high pressure in front of them blocking them. Let's see how it pans out so very slow here. Fortunately for them, the boats behind not have that much breeze either. And here they go south, south south. But now they have respected the first ice gate, and you can see that they keep on plunging south. Trying to get away of the claws of the high pressure and getting into the strong winds to the south. There's a big low pressure system coming in from the west again. All the way moving from west to east and there you go. High pressure here now. And go further and further south. Interesting point here is that you see the ice gate is here, the ice gate is there. They looked all the way down south right? And the next Barcelona World's race, they decided to do a different system, instead of having these ice gates relatively north, so that if the boats go down south it would look like it still don't enter too far south. Alright, the whole ice area will be encapsulated, if you will, by an exclusion zone, which means that the absolute points would have to go, will be further South, but it will have the same safety. Anyway, let's go forward, all right. High pressure cell over here, boats. Staying south, staying south. But by now they have to come back up north. There's no way around it. Fortunately for them, the boats behind have the same problem. Let's stop here, because didn't expect for this starting to happen. Tropical system. This one had a name. It was called Atu. Coming down from the North, coming down from the tropics. Looks very menacing at this point in time. Winds, and all that sort of stuff. A low pressure system gets it's energy out of the difference between cold and warm. If it's tropical, like that's a hurricane, it's basically being fed by warm water. As it moves south, it will get cut from it's power supply, if you will, from its flow, right? And we'll have to make a transition from what they call a warm core to a cold core. Most of them don't succeed doing that, you know? They will just die. Transfer all the energy into rain, and just stay on place. And fitter out, basically. Some others manage to get down into the flow, get an injection of cold air, get regenerated and become a normal frontal depression. A tropical depression doesn't have any front because all the verticalation, all the circulation is like that in a tropical depression. For the folks back here, this looks very menacing. At the moment here there will be warning sounds, hurricane warnings and Al this sort of stuff. The trek was forecast at the time to go down here. When does it start losing its energy? It starts losing its energy when its about here. It's all based on water temperature. At a certain water temperature it starts losing its energy. Wind loses energy in time, so that the boats can still safely navigate, or do they have to take evasive action? It's starting to come down. You can already see that the cold is getting lighter, the breeze is already started to get lighter, less wind. However the system is expanding. Geographically it's expanding. Here you can see that those boats here, are sort of going towards it, trying to find the winds that will allow them to take and then go back there. Of course there's a little bit of risk involved of the winds being fairly strong, what is happening now. We can see here that it goes regenerated and some of the boats had quite a lot of wind. Some of the boats actually sail back for a little while to try to avoid the worst of it. Here, you can see that Atu was now getting in through the ocean, gets regenerated, and becomes a classical. Meanwhile, back in the front, these boats are not even concerned with it. They're not that far ahead. That they're just dealing with the sudden ocean lows to the south, high pressures to the north. Back behind, still in the Pacific, so you can see here, there was a big low pressure system over here, north-westerlies, main center over here, secondary center over here, south-westerlies behind. Main bulk of the fleet is sailing the south-westerlies. All right, and we'll probably get another system before they get to Cape Horn. Approach to Cape Horn is always a little bit tricky. It is very far south. It's about 56 and a half, which is the furthest south they've been, basically. Right, and the other thing is that there's a big mountain ridge over here, the Andes. So if there's any big northwesterly gale coming in, it gets compressed against the mountains. Which makes Cape Horn so infamous for being extremely windy with extremely bad sea state. Let's have a look here. Let's go forward. You can see that those boats are sailing in whatever's left of the southwesterly flow. And here, you can slowly see a new system starting to move in, right? Front. Here's the front, westerly, behind it. Right. As it squashes up towards South America, you can see the breeze building here. And some of the breeze here is very, very strong now. Those boats coming in now you can see that they've got really, really strong north-westerlies, right, coming in very fast to Cape Horn. It's always a choice here, if you stay south try to stay in more pressure, more weight. Or if you sort of hike up north here, in case this strong northwest wind comes in, so that you've got some angle to come into Cape Horn, and settle fast, safe, and more comfortable angle. Again here, you can see another sequence of strong northwest leads. Most of the boats come in fairly far north. Coming in from the south like this is a much higher risk option. So here we are. The last week of March. This last competitor. The last edition of the Barcelona World Race, you can see now that we're coming up to the equivalent of October for the people living in the Northern Hemisphere in about a week, and this big low pressure here, you know, gales, days are getting shorter. This boat's trying to reach Cape Horn and this system behind them looks quite menacing. I mean those arrows here they could have led to 45 notes out of grid foul with ten meters winds. In reality, this will be gusting 60, 65 you know, gale force before ten to 11, right, really bad weather in most desolate place on Earth. So if we go forward we can see that there they are, they're being caught up by this low. It's getting stronger and stronger, right, we've now got this whole area here of sustained 45 knot wind. Gust will be at least 20% more. See, over here the sea's still okay-ish, but once they get into here, once this takes over, this northwesterly swell that is being built up by this wind will then be overtaken by a southerly wind on top of it, leading to cross seas, very confused, very high, both breaking and non-breaking conditions, basically. There you go. Now they get overtaken by the low, and now they'll be in this really cross sea that I just mentioned. Here's the center of the low. All right, the loading docks have changed now basically. Going a little bit lighter now, low system is moving through. They're getting some kind of relief, they have finally reached Cape Horn before the next system moves in. It's not a place you would want to be in autumn nor in winter. The other thing to keep in mind Is that later in the season as it gets colder and colder the air isn't the same. A cubic meter of air that is cold has more density has more push to it than a cubic meter of air that is warm. So 20 knots in the trade winds is very pleasant. 20 knots down here is already sort of. Tough, right? Once we start talking about 30 knots and cold air, it is as bad as it can be in 35, 40 knots, nice Mediterranean mistral conditions or something, warm air. No big deal. Down in Southern Ocean, 40 knots, 50 knots, it is as bad as it gets basically.
