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Nature / Earth

Water, wildlife and the forces that shape our home. Start with a question about the world outside.

Nature / Earth / Field notes

How stalactites and stalagmites grow from water travelling through rock

Ceiling down, floor up: the directions are easy to remember. The chemistry explains why water leaves stone behind—and why size does not reveal age.

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Nature / Earth / Field notes

Why geysers erupt while most hot springs do not

Heat and water are only part of the explanation. Restricted underground plumbing helps turn stored thermal energy into an eruption.

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Nature / Earth / Field notes

How glaciers widen a valley into a U

A small river can run through a valley far wider than its channel. Earlier moving ice helps explain the mismatch.

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Nature / Earth / Field notes

How rivers carve round potholes into solid rock

Swirling water and sediment can wear a smooth cavity into bedrock. A dry hollow may record a river that has moved on.

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Nature / Earth / Field notes

Why a smooth swell breaks into surf near the shore

A wave can travel a long way before it tumbles over. The change happens when its motion interacts with shallower water and the seabed.

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Nature / Earth / Field notes

Why the grass can be wet when it has not rained

Dew forms at a cooling surface. That small detail explains why a lawn, a path and a thermometer can tell different stories about the same night.

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Nature / Earth / Field notes

Why cooling basalt breaks into columns

Those regular stone pillars began as cracks in cooling rock. Their shapes tell a different story from the erosion that later exposed them.

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Nature / Earth / Field notes

How rock walls become Bryce Canyon’s hoodoos

Cracks, freezing water and unequal weathering help turn rock walls into isolated spires. The shape records what has been removed.

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Nature / Earth / Field notes

How a river bend becomes an oxbow lake

A curved lake can preserve an old river route. Erosion makes the bend move; a cutoff and deposited sediment change its connection.

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Nature / Earth / Field notes

Why lenticular clouds seem to stay still in the wind

The air keeps moving through these mountain clouds. Their steady shape comes from a cycle of formation and evaporation.

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Nature / Earth / Field notes

Why glacier ice looks blue while snow looks white

The difference lies in the route light takes through ice, and how soon it is scattered back toward your eyes.

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Nature / Earth / Field notes

What makes sea foam, and why a photograph cannot identify its source

Wind, waves and organic matter can make a foamy shoreline. The bubbles alone do not diagnose the water.

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