Issue 41: Size Comparisons
September 1, 2022
We compare the sizes of places around the world; ice melts in Greenland; ghastly secrets are revealed in Lake Natron; and a city is built in the Nevada desert.
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Feature Story: Size Comparisons
It’s difficult for humans to comprehend the true size of things, like the number of stars in the universe or the dimensions of a moose (they’re huge). We struggle when the measurement gets too large. So we often turn to comparisons when trying to communicate big numbers. The problem is that the comparison can sometimes be even more mystifying, like saying an iceberg is as large as a quarter of Wales or that 50,000 Olympic-size pools worth of rain fell in 5 hours.
We’re guilty of this fault too: in Issue 26 we compared an area of land to the size of Rhode Island. While we technically know the state is over 2,600 km2 (1,000 mi2), we don’t really have a sense for how large that is. This challenge is particularly common with satellite images: the size of what you’re looking at from space is not always obvious. Us non-astronauts — terranauts, if you will — are unaccustomed to this perspective of the planet. And a place’s size or scale can be near impossible to discern when devoid of familiar sights. So this week we’re comparing images where size isn’t as obvious to areas with ample landmarks, like cities.
The images in every diptych in this issue are identically scaled so that there’s a direct 1:1 correlation between their sizes. The following images, for example, each have a dimension of 12 x 15 km (7.5 x 9.3 miles). On the left is a tiny, tiny section of the 6,400 km+ (4,000 mile)-long Amazon River and on the right is part of the metropolis of São Paulo, Brazil.
It shouldn’t come as a surprise, but we’re visual learners here at Snapshots. We can read that the Grand Canyon is 447 km (278 mi)-long and covers over 486,000 hectares (1.2 million acres), but we get lost the moment the numbers hit triple digits. What hammers it home for us is seeing how it stacks up against the city of Phoenix.
The revered and sacred sandstone monolith called Uluru literally stands out from its environment in the Australian Outback, but there’s little else around it for comparison. So we placed it next to the Super Pit, a massive open-cut gold mine next to the city of Kalgoorlie. Even though their respective areas are comparable, the pit is actually twice as deep as Uluru is high. Representing 3-dimensions through 2D mediums is tricky. For satellites, the top-down perspective flattens scenes and makes depth hard to determine. But for global maps, the representation of space can be far more deceptive.
Since it was created in 1569, the Mercator projection has reigned as the standard model for map-making and was even used by Google Maps until 2018. It’s the classic north-is-up-south-is-down world map that adorned the walls of your childhood classrooms. While useful in many respects, it has a nasty little tendency of distorting land masses the closer you get to the poles, equating places in size like Greenland and Africa (Africa is 14 times larger).
The more abstract the satellite image, the vaguer the size. That’s why cities make good references — because they contain a multitude of landmarks and are often more familiar than, say, the wavy white sands underneath shallow seas in The Bahamas. Even if you’ve never been to Havana, it’s likely easier to grasp than an obscure ecosystem.
At the end of the day, it’ll always be a challenge to adequately convey the size of large or unfamiliar places. Comparisons don’t necessarily solve the problem, but they lend scale and help expand our understanding of each. And while we encourage communicators to continue using creative methods to repackage large statistics into easy analogies, we’re not world-class athletes, so leave the Olympic-sized swimming pools out of it.
Greenland Melt
Even if it isn’t quite the size of Africa, Greenland is still massive. And over 80% of the Arctic island is covered in ice — but not for long. A study published this week claims that even if greenhouse gas emissions halted today, 3.3% of the Greenland ice sheet will melt. That’s enough to raise global sea level by nearly 1 foot (0.3 m). Researchers identified meltwater runoff as the primary driver, and the landmass holds enough ice that, if all melted, could raise sea levels by 25 feet globally. Every inch of sea level rise will have catastrophic consequences for coastal cities around the world.
Here’s swirling galaxies of ice around one of Greenland’s glaciers shown next to Miami Beach, Florida. It’s a comparison not necessarily notable in terms of size, but profound in its implications.
What in the World: Lake Natron
Around the world drought is drying up lakes and rivers and revealing all sorts of secrets buried beneath their covert waters: shipwrecks, hunger stones, bodies in barrels (yikes), and abandoned towns. But in the alkaline waters of Lake Natron, the secrets are simpler but perhaps equally grim: bright red patterns and birds seemingly turned to stone.
Lake Natron is a shallow salt lake in Tanzania that loses water only through evaporation. What’s left behind are salts and natron, a sodium mixture which gives the hot (100°F+) water its basic (10+ pH) composition. Algae gives the lake its notable red color and thrives in its extreme environment. As do flamingos that eat said algae. But migrating birds that accidentally crash into its chemical-rich waters die and leave behind calcified skeletons. And while the birds are too small for our satellites to capture, you can still be sure we’re including these images in our Halloween issue on Earth’s spookiest places.
Change of the Week: Burning Man
Burning Man is fully stoked and firing on all cylinders for the first time since 2019 with tens of thousands of people attending the event. The art festival focuses on community, self-reliance, and self-expression, and the theme this year is Waking Dreams. At the end of the week the bright-eyed, bike-traveling, wallet-less, dust-smeared revelers will burn the eponymous wooden man. Watch as Black Rock City is built throughout August.
