Let's see how we can add ready-made tropical storm layers to a web map. We're starting in ArcGIS Online Map Viewer, and we're going click the basemap gallery in the context start toolbar just here on the left-hand side. And I'm gonna change the basemap to imagery hybrid because that's gonna suit our work best. Then we're going to add browse layers. So we're going to click add to browse layers, and we're gonna make sure we're looking in ArcGIS Online, not my content. And the layer we're gonna search for is called prominent latitudes and longitudes. You just have to type latitude into the search, and you should find that as one of the top two layers. And if we click add, it will put it onto the map as a new layer, and when we do that, its properties will appear as well. Then we click the layers panel on the left to show the layer that we've just added. And in fact, it's more than one layer. It's got some sub layers, which we can reveal by clicking the small arrow, and we can hide one of the layers by clicking the visibility button just here. And we're going to click to hide the latitudes and longitudes so that we just show the major parallels and meridians. Then I'm going to head back to the browse layers button to search for another layer. This time it's going to be historical hurricane tracks, once again in ArcGIS Online. So I type that into there and sure enough, there's the layer that I need. I'm going to click add so that I can see that, and it should appear on the map, and it's quite a dramatic sight. This layer, historical hurricane tracks, shows tropical storms going back a long time, to around 1853, so it's a very big dataset. We're just gonna hide the properties layer by clicking properties over here so that we can see the map a little bit more clearly. And another thing we're gonna do to make it even better is we're going to look at the legend for the map because that's going to help us to understand what the meaning of the colours is. So if we click legend, the colours reveal the magnitude of the storms at different stages of their tracks. Now we can explore the map using pan and zoom in the usual way, and this will help us to see what the overall spatial pattern is of the tropical storms and the way in which they compare with the latitude and longitude layers. In particular, we can see how the most intense activity is concentrated in between the equator and the two tropics, the Tropical of Cancer and the Tropic of Capricorn. In the northern hemisphere, we see how the North Atlantic and the Northeast Pacific have many tropical storms. In the southern hemisphere, we have a similar pattern. The Indian Ocean gets a lot of storms, so does the Southwest Pacific. However, there are exceptions with the South Atlantic where there don't appear to be very many at all, just a couple here, and also in the Southeast Pacific where there are very few, if any, tropical storms. Crucially, one generalisation which holds true is that we don't see any tropical storm activity actually along the equator at all, even if we zoom in. A few storms get close to the equator, but one thing that never happens is that they don't cross the equator. A key reason for this is that the Coriolis force, which drives the rotation of hurricanes, is almost non-existent along the equator. And a final point to make is that as the storms move further north, we see the intensity reducing, the colour of the lines tends to be a lighter blue, and that's because they're losing energy as they move over the cooler waters to the north and to the south of the tropics. So we've seen a way that GIS can help us to appreciate the spatial pattern of tropical storms. Let's save our work, saving it for the first time. So we click save and save as. And we're going to give our map the title of Tropical storms and save it into our content. It's not uncommon for a map like this, where we're using ready-made data, to be showing a very large amount of data, what we've called big data. What we want to do is to be able to pick out one or two aspects of it so that we can study them. To do that, we can use something called filters. So we're going to see how to do that. First of all, we go to the layers panel and find the historical hurricane tracks, and we'll see three dots at the end of the layer. If we click those and then click show properties, the panel on the right opens up, and part of that is something called a filter, which is shown by this symbol here, which looks like a funnel. So we click filter and we're invited to set a condition for the filter. So the first condition we're going to set is for the hurricane's name, and we're going to click the selection box for the attributes, click name. And then in the selection here, we're going to see if we can find one. The one we're going to look for has a name, Ian, and we can see it's listed there. So we click Ian, and what we find is that there is more than one hurricane over the years called Ian. We only want to look at one of them. So what we can do is set another condition. We add new, and we're going to look for the year in which there was a Hurricane Ian. And in the dropdown menu, we type 2022 to find the Hurricane Ian, which happened in late September, early October of that year. So having started with a kind of spaghetti of lines of tracks of hurricanes over very, very many years, we're now left with just one that we can look at and study. So now is quite a good time to save our map. It's a quick save this time because we've already named it, and we're also gonna open the legend again so that we can easily interpret the symbology for Hurricane Ian. We can see how Hurricane Ian started as a tropical depression just north of Venezuela, north of Caracas. And it tracked westward across the Caribbean sea, staying mainly in the open sea, and then it began to move northwest and eventually, as a category 3 tracked across Cuba just here. I'll just zoom out so you can see Cuba. And then it carried on further north and eventually made landfall on the western side of Florida, quite near a place called Punta Gorda. You can see the town Punta Gorda just here. If we zoom out again, the hurricane tracked across Florida, doing quite a lot of damage. Then it went to the open sea over the Atlantic and began to lose some of its power, but it was only at sea for a little while, and then it returned to the North Carolina coast near Charleston, and then carried on inland, and produced quite a lot of rainfall there, and eventually fizzled out, and died out over the mainland part of the northeast United States, mainly because it lost its source of energy because it was no longer over open water. And the blue colours tell us that.