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  • From espressos and cappuccinos to cafe au lait and plain black, there's a coffee out

  • there for almost everyone.

  • We can even visualize it on a map like this, where the color of each country represents

  • how much coffee they drink per person.

  • So much of the world loves coffee!

  • And I agree.

  • For me there's nothing better than a morning latte.

  • But for coffee to get to my favorite coffee shop, it first has to make it through a pretty

  • long journey.

  • We won't go bananas and get into the full geographic story of coffee, but in 2020 coffee

  • is mostly grown in theBean Belt,” which is -- oh I'll just show you.

  • My favorite coffee shop is much closer though -- over on Elm Street.

  • From my house, take a left at the end of the street, go to the bottom of the hill, and

  • take another left, past the house where the grey cat is always sitting on the porch.

  • A few blocks later, there's that beautiful garden along the side of the yellow house.

  • Walk past there, take a right at the next corner, and the café is straight ahead.

  • At least, that's the mental map I follow every morning.

  • We all have maps we use as tools to help us navigate or better understand wherever we are.

  • And in geography, we use maps to study, analyze, and interpret spaces, places, and human-environment interactions.

  • We use maps in all shapes and sizes to tell the story of the Earth.

  • They're colorful, detailed, and lots of times, difficult to fold!

  • I'm Alizé Carrère and this is Crash Course Geography.

  • INTRO

  • Formally, a map is a symbolic representation of space, which is all the facts and features

  • about a particular spot.

  • Maps can be used to compare spaces (and places) on Earth and beyond or shape our sense of

  • reality.

  • Like, when you searchmapon the internet, this world map is one of the first things

  • that comes up.

  • A world map is a type of reference map.

  • Reference maps can show mountains, cities, oceans, elevation -- everything people might

  • say "yep, that's there."

  • But the Earth is almost spheroid, or a slightly wonky sphere.

  • So this reference map also has to do the hard work of representing our three-dimensional

  • world in just two-dimensions.

  • Like taking the 3D Earth and squishing it onto paper or a flat computer screen.

  • Imagine doing that with a tomato.

  • What a mess.

  • For cartographers, or map-makers, it's a challenge with many solutions.

  • They need to pick which data they want to focus on, and the type of map they pick often

  • depends on what story they want to tell.

  • For example, we might want to use these three maps to talk about the number of people in

  • each country around the world.

  • They're thematic maps, which visualize data about a particular topic across a space.

  • Instead of being something we'd use to navigate on a cross-country road trip, thematic maps

  • tackle abstract ideas, like average rainfall or voting results by political party, and

  • explore how frequency, concentration and patterns are distributed across a space.

  • For example, these three thematic maps are designed to visualize population data.

  • First, we have a choropleth map, which shows how a theme like population changes over a

  • particular space using different colors or shadings of colors.

  • This is shown in the map's key or legend which unlocks the map and shows us how to

  • get into the map and interpret it.

  • Notice how the key moves from light purple to deep violet depending on the population

  • density -- the number of people per some amount of area.

  • When we look at this, we can tell pretty quickly the population density in most of South America

  • is quite low.

  • Except for the northern tip of the continent, there are between 0 and 25 people per square

  • kilometer.

  • But wait.

  • As of 2020, Sao Paulo in Brazil is actually one of the 20 most populated cities in the

  • world.

  • So nowhere in Brazil has more than 25 people per square kilometer?

  • Nowhere?

  • Choropleth maps are useful because they quickly tell us which countries or regions belong

  • in the same category overall.

  • With a glance we see Australia and Canada and Russia and most of South America all fit

  • in the same population density category.

  • But by shading a whole area, choropleth maps can make things look a little too simple,

  • which can be a problem.

  • They imply there's an evenness to whatever they're showing -- even though there are parts

  • of Sao Paulo with wayyy more than 25 people per square kilometer and other parts of Brazil

  • with absolutely no people.

  • Let's try a different thematic map that will let us be a bit more specific.

  • A dot density map uses a dot to represent a key feature or attribute.

  • The cartographer decided that each dot on this map represents 100,000 people.

  • So while the choropleth map showed the general population spread out over an entire country,

  • this dot density map has more granularity and shows where within a country people live.

  • More or less.

  • We can see the coasts of Brazil have more dots -- and more people.

  • But take a look at the Sahara or Siberia.

  • No one lives exactly where those dots are!

  • The cartographer also decided where to place each dot to summarize population data.

  • But it's a simplification that could mislead someone if they're not paying close attention

  • like we are!

  • A dot doesn't necessarily mean 100,000 people live exactly there.

  • Cartographers are always trying to make maps easily readable, but all the choices they

  • make can influence accuracy.

  • For example, if we changed how our dot density map is projected, or how the 3D Earth was

  • flattened into 2D, the size and shape of the continents would shift, and so would the dots.

  • We might accidentally imply some areas have a closer population density while others are

  • more spread out.

  • Our last thematic map for today is a cartogram map, which uses size to compare data -- like

  • population density -- regardless of the actual space these regions take up on the Earth's

  • surface.

  • With this map, the really populous countries are giant, while ones with smaller populations

  • are tiny.

  • But it looks weird to us or at least me, because we're used to maps that tell us something

  • about the physical space that countries and continents take up.

  • India has a much bigger population, but in real life Australia is a muuuuch larger country

  • -- it's about 7.7 million square kilometers while India is less than half the size with

  • 3.28 million square kilometers.

  • Each of these thematic maps uses a different lens to tell the story of the world population.

  • Different maps represent data in different ways.

  • And the more information a geographer has, the better interpretations they can make about

  • a particular story -- like human population.

  • Of course, there are many, many more stories to tell, so there are many, many more maps.

  • And by helping us visualize data across space, maps actually shape our perception of reality

  • too!

  • Alright, that sounds a bit melodramatic.

  • But every map was made by a person making choices.

  • And those choices (however thoughtful, or simple, or unintentionally biased) have an

  • impact on how we imagine the world.

  • Like, we're so used to seeing north at the top of a map and south at the bottom.

  • But why?

  • Well, that's a choice made by a cartographer.

  • Other cartographers tried something different with a Fuller projection that unfolds the

  • Earth and ends up with a completely different orientation without distorting anything.

  • This map doesn't have Greenland at the very top of the map, like we might be used to.

  • There's more than one way to represent Earth.

  • By thinking about what a map was supposed to be used for, we can spot these obvious

  • or not-so-obvious choices made by cartographers.

  • For centuries humans have been using maps as navigational tools to help us understand

  • our physical surroundings.

  • Stick charts like these are made of fibers from coconuts and shells that were developed

  • by mariners from the Marshall Islands.

  • These charts weren't used to navigate exactly the same way that we use maps today.

  • They weren't carried along in the boats, but studied and memorized to get a better

  • idea of the islands, waves, winds, and currents in the Pacific Ocean.

  • Stick charts were personal -- mariners had their own stick charts that they used to get

  • back to places they'd visited.

  • Kinda like my mental map to my favorite coffee shop.

  • These charts were someone's own perception of the space in their individual world.

  • Maps can also be used politically, and the choices about where to draw borders on a map

  • are giving spaces a national identity.

  • For example, there's a dispute over territory in Antarctica and some nearby islands that's

  • currently on pause thanks to a 1959 treaty.

  • Originally the 12 countries whose scientists had been conducting research on the continent

  • signed and agreed that no activities taking place would mean they'd claimed the territory.

  • But in the 1960s, despite the treaty, Argentina published maps claiming territory in Antarctica.

  • So anyone who uses those maps would perceive this land as part of Argentina.

  • But where to draw borders isn't the only political decision a cartographer can make.

  • Let's go to the Thought Bubble.

  • Let's say it's the 1950s and we're U.S. cartographers working on a new world map.

  • The Cold War between the United States and the Soviet Union is nearing its height, and

  • the tension can influence our mapmaking decisions.

  • First, we have to choose a kind of projection, like the Mercator projection.

  • First made in 1569 by the Flemish cartographer Gerardus Mercator, this type of map basically

  • turns the spheroid Earth into a cylinder.

  • The Mercator projection shows the lines of longitude, or meridians, as equally spaced

  • and parallel vertical lines traversing pole to pole.

  • The lines of latitude, or parallels, are also parallel lines on this map, but get spaced

  • farther apart as we move north or south of the equator.

  • (On a globe, meridians aren't equally spaced, but curve together at the poles.)

  • With this layout, the scale gets distorted and areas farther away from the equator appear

  • bigger than they really are.

  • Like, look at Greenland.

  • It's essentially the same size as all of Africa!

  • It's not that this representation is wrong -- every map choice comes with flaws.

  • But by choosing a Mercator projection, the USSR looks large and menacing.

  • That's just the beginning, so we sketch out country borders.

  • And now it's time to add color.

  • As US based cartographers, red is our first choice for the USSR.

  • In the West, “Redor theRed Scareare synonymous with fear of communism.

  • Representing a major foe to the United States in red sends an immediate message to the viewer.

  • But for further effect, let's add the hammer and sickle -- weapons reminiscent of the scythe

  • of Death and the symbol of the Soviet era, which evoked fear in Americans.

  • As you can see, with just a few mapmaking choices, we can actually help stir up some

  • major nationalistic emotion.

  • Thanks Thought Bubble!

  • Though the Cold War is over, our maps still reflect nationalistic fervor in more modern

  • times.

  • We like to think of data and numbers as being objective, but how data is displayed on maps

  • can affect what people believe about the world.

  • Like these two maps both show the Hispanic population in Florida based on the 2000 Census.

  • They look like very different maps, but it's actually the same data!

  • Maps can even be used to tell stories about societal problems.

  • On this map, major chemical accidents, environmental disasters, freak weather patterns, and deforestation

  • are all included with different symbols.

  • So looking at this map might make you feel like the Earth experienced great environmental

  • stress in the 1980s and 1990s.

  • And that's a choice the cartographer made.

  • Maps can make strong arguments because they pull a lot of visual information together,

  • which can increase our awareness about certain issues -- or greatly skew our understanding

  • of the world.

  • Maps are powerful tools, and they'll be a crucial part of our journey through geography.

  • But we can't rely on just one map.

  • Every map is telling a particular story with how it's visualizing data, and it's our

  • job to think critically about what's being presented to us.

  • Many maps and borders represent modern geopolitical divisions that have often been decided without

  • the consultation, permission, or recognition of the land's original inhabitants.

  • Many geographical place names also don't reflect the Indigenous or Aboriginal peoples languages.

  • So we at Crash Course want to acknowledge these peoples' traditional and ongoing relationship

  • with that land and all the physical and human geographical elements of it.

  • We encourage you to learn about the history of the place you call home through resources

  • like native-lands.ca and by engaging with your local Indigenous and Aboriginal nations

  • through the websites and resources they provide.

  • Thanks for watching this episode of Crash Course Geography which was made with the help

  • of all these nice people.

  • If you would like to help keep all Crash Course free for everyone, forever, please consider

  • joining our community on Patreon.

From espressos and cappuccinos to cafe au lait and plain black, there's a coffee out

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地理2(What is a Map? Crash Course Geography #2)

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    joey joey 發佈於 2022 年 02 月 27 日
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