ShmoopTube

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We live in a modern high-tech world self-driving cars exist [woman driving without her hands touching the steering wheel]

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drones can deliver packages the day we order them and we can unlock our phones

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[phone being unlocked with a thumb print] with our thumb print like we're spies so this old thing it's boring after all

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it's just a flat piece of paper how can it help to compete with satellite

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imagery or 3D holograms well as it turns out they're actually not too bad at

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capturing 3d information if you can read a topographic map you should be able to [image of a topographic map]

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tell how the ground goes up and down just like you would from a 3d shape and

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unlike a 3d hologram they won't run out of batteries when you're on top of a [3D hologram fading away from running out of batteries]

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mountain see that boring old paper map will come in handy when the only folks

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who know the way back down are the mountain bears to show different [mountain bear chasing people with a topographic map]

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elevations topographic maps use contour lines which are lines that connect

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points of equal elevation so if you see a contour line on a map you know that [Coop pointing to a definition of contour lines on a chalkboard]

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every point on that line is the same height in the real world that means that

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contour lines can't cross because that would mean the points where they cross [example of contour lines crossing on a topographic map]

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would be at two different elevations which is impossible some contour lines

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include even more information for example index contours are labeled with

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an elevation so you can tell just how high does points are even if you didn't [arrow pointing to index contours on the topographic map]

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bring hundreds of meters of measuring tape and at the very tops of hills and

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mountains you'll see closed circles marking off the very highest elevation

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which we would have marked with dance parties and free Gatorade but circles [people at the highest elevation of a mountain drinking gatorade]

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works too we also find closed circles around depressions where the ground is

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getting lower these also come with little lines called hachure marks which [example of hachure marks by a lake on a topographic map]

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point down slope towards the center of the depression with the help of a

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topographic map we can learn all sorts of stuff about the land they describe

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for example the gaps between contour lines tells us how slowly or quickly the [arrow pointing to the gaps between the contour lines]

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elevation is rising we call the difference in elevation between two

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contour lines the contour interval if your map has a contour interval of 5 [person holding a topographic map]

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feet that means that between any two contour lines the ground is rising or

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falling by 5 feet this particular contour interval will be listed

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somewhere on your map but whatever the interval is contour lines that are [contour interval of 34 shown on a topographic map]

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closer together show steepness since elevation is changing quickly that's

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really good to know if you happen to like taking gentle walks rather than [man with his hands on his hips walking through rocky terrain]

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experiencing we don't know a terrifying day of rock climbing not that that

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happened to us or anything and believe it or not topographical maps can even tell

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you which way water is flowing when contour lines cross the valley or stream [example of topographic map showing which direction water is flowing]

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they make a series of v's or u's these also point upstream so the water is

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flowing in the opposite direction we'd like to see Siri do that we might need a [girl throwing her iphone into the river]

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new phone

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