Slippery when frozen (Vox)
by Brian Resnick
It’s a question we rarely think about as we slip and slide on frozen sidewalks and highways, but why is ice slippery? It turns out scientists have struggled to come up with an answer that explains the extremely unusual properties of frozen water.

Why measles is spreading in Washington (The Cut)
by Amanda Arnold
Measles is spreading among children in Washington State. Public health officials say they’re not surprised, and they’re also clear on the solution to stopping this from happening again.

Climate change through genocide (BBC)
by Jonathan Amos
In 1500, 60 million people lived in the Americas. Over the next 100 years, disease and genocide killed 90 percent of them, resulting in enough reforestation of land to measurably cool the earth.

The church forests of Ethiopia (Nature)
by Alison Abbott
Ethiopia was once covered in forests. Today, the lush, biodiverse climates have dwindled to islands of green preserved by the nation’s churches. Ecologists and priests are working together to document, protect, and expand the church forests.

The foodie world of Medieval Baghdad (Atlas Obscura)
by Anne Ewbank
Medieval Baghdad was at the center of trade routes bringing exotic foods from all directions. This produced a thriving gourmand culture, and even a kind of Iron Chef competition among elites.

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