Issue 53: Antarctica
December 1, 2022
In this week’s issue: We round the horn to explore Earth’s icy southern continent; a valley creates an optical illusion in Algeria; a contentious dam fills a reservoir in Ethiopia; and snow falls on Yosemite.
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Feature Story: Antarctica
Antarctica is the continent of -ests: coldest, driest, iciest, windiest, and so cold it’s worth mentioning twice-est. The frozen landmass blankets the Earth’s southern pole in a cap of ice larger than Europe and boasts a permanent human population of 0. And despite being inhospitable to most life itself, Antarctica regulates climatic conditions vital to our survival. It’s a record of the planet’s past and a direct influence on its future.
Antarctica is hard to get to (in case that wasn’t clear). It’s at the literal end of the Earth, after all. So if you’re not prepared to take the long journey there yet, come round the horn with us and explore the planet’s seventh — and dare we say coolest — continent.
Because of its inaccessibility and scientific importance, those traveling to Antarctica mostly consist of intrepid explorers and researchers. One of those first explorers, Ernest Shackleton, lost his ship to an ice floe in 1914 but gained an epic tale of survival in harsh Antarctic conditions. Over a century later, a team of scientists and meteorologists boarded the ice-breaking S.A. Agulhas II to find the shipwreck and study how greenhouse gases are changing the Antarctic ice pack.
Remote sensing technology is particularly well-suited to studying the Antarctic — partly because of its inaccessibility and partly because of the unique tools it provides. Scientists are using remote sensing data to study everything from changes in surface elevation to penguin colonies (more on that later). And some researchers using satellites to study water tracks on the Antarctic ice indicate that similar processes can be used for studying the surface of Mars (in case you needed any further indication of the continent’s extreme and inhospitable conditions).
Antarctica is also home to oddities strange and creepy enough to make our list of spooky places from space. Blood Falls is one of these sights with a name that leaves little room for interpretation. From space it may seem tame, but the pictures up close are frankly terrifying. It looks like a five-story tall sheet of blood emerging from the glacier. Don’t worry though. It’s not actually blood. It’s subglacial water so salty it can’t be frozen and filled with so much iron it oxidizes and rusts — or so we’re told.
It might surprise you to hear that there’s a fair amount of volcanic activity among the continent’s icy crust. But it’s been a big week (and year) for volcanoes, so maybe you’re unfazed by the news. Regardless, here’s Mount Erebus, the southernmost active volcano in the world.
Antarctica has 0 permanent human residents, but there are some animals that live there year-round. And it turns out that you can track them by their excrement. Researchers use these guano-smears on the ice to follow waddling penguin colonies.
Antarctica’s importance can’t be overstated — whether it’s the continent’s data on our climate’s distant past, what it reveals about changes now, or simply its evocative and imposing beauty. Antarctica is colossal, intimidating, and we’d be lying if we said we weren’t just a little afraid of it. But we’d like to keep as it is — after all, we prefer our Earth on the rocks.
Bonus: One of our favorite images to come from the icy south is this rippling pattern on the Dotson Ice Shelf that looks like a giant claw mark.
Satellite Explainer: Relief Inversion
Sometimes the eyes do lie, chico. There’s an optical illusion somewhat occasionally found within satellite imagery called relief inversion. Generally speaking, it’s what happens when our eyes have a difficult time discerning whether a mountain is a valley or vice versa. The bird’s-eye-perspective tends to remove depth. And when a landscape is lit in perhaps peculiar ways, voila: relief inversion. So we ask you, valley or mountain?
Oh, and same for dunes too.
Grand Dam
The Grand Ethiopian Renaissance Dam is an almost completed, highly controversial project with the unfortunate acronym of GERD. The dam seeks to produce electricity to half of Ethiopians currently without power and pave the way for further industrialization. But its construction has literal downstream consequences. Both Egypt and Sudan depend on the steady flow of Nile water. And with water resources already tightening, the dam stands as a potential threat to the region’s water security.
Construction of GERD began in 2011. And Ethiopia intends on having the reservoir entirely filled by 2023 — a deadline deplored by the downstream countries hoping for a slower process. Daily Overview created the timelapse above to illustrate just how much water is being stored for the reservoir, and we created our own below of the dam itself.
Change of the Week: Yosemite Valley
In Yosemite, climbers rise but snow falls (nailed it). A cold front passed through the Sierra Nevada mountain range earlier this month, blanketing the region in snow and changing conditions dramatically. Check out the rotating color palette around Yosemite Valley and the stark shadows cast by the southern ridge.
