Dew

Dew had learned about the air's water as a tadpole-turned-frog.

The first time she saw her pond mysteriously ringed with fog one cool dawn, she was frightened — a ghostly cloud sitting right on the water, appearing from nowhere, and she was sure something strange and maybe dangerous was happening.

Her grandmother, an old frog with knowing eyes, sat with her in the mist. "It's not a ghost, and it's nothing to fear," she said. "It's the air letting go of its water, right down here where it's coolest." She waved a webbed hand through the fog. "The air over our warm pond held lots of invisible water all night. Then, near dawn, the air cooled — and cool air can't hold as much — so the extra water came out, right here, as a low cloud sitting on the water. That's fog: dew that formed in the air itself instead of on the grass." She smiled. "Same thing as the dewdrops on the reeds. The air just got too cool to keep all its water, and let some go."

Dew looked at the fog differently after that — not a ghost, but the visible sign of cool air wringing out its water. And she learned to expect it: clear cool nights, damp mornings, fog on the warm pond. The frightened, something-strange feeling turned into a bright, knowing calm. The fog wasn't a mystery. It was just the air letting go of water it could no longer hold.

When she was older, Dew hopped to the WeatherForge academy, where Gale, who ran it, asked, "Where does dew come from, if not from rain?"

Dew didn't answer with a speech. She breathed on her cold metal cup, and it fogged and beaded. "From the air itself," she said. "The air holds invisible water, and warm air holds more than cool air. Cool the air past its dew point — the temperature where it's holding all it can — and the extra water comes out: dew on cool grass, fog over cool water, drops on my cold cup." She wiped a bead. "That's why clear cool nights bring dewy mornings — the ground cools fast, chills the air just above it, and the air lets go."

Gale's eyes crinkled warmly. "Some think dew is a kind of secret rain," Gale said.

"It's the air wringing itself out, not rain falling," Dew said. "Ordinary, everywhere." Gale smiled. "Then come in," Gale said. "WeatherForge needs someone who knows where the morning wet comes from."

In her classroom one afternoon, a puzzled young shrew stared at a sweating glass of cold water.

"My glass is dripping," the shrew said, "and it's making a puddle, and I didn't spill anything. Is the glass LEAKING? Where's the water coming from? It's spooky."

"The glass isn't leaking — the water is coming out of the AIR," Dew said gently. "Let me show you." She set a cold cup on the table, and soon it beaded with water. "See? The air right next to this cold cup gets chilled by it. And chilled air can't hold as much water, so the extra comes out — right onto the cold glass, as those drops." She wiped the cup. "It's the SAME thing as dew on the grass: a cool surface chills the nearby air past its dew point, and the air lets go of water onto it. Your cold drink is just making its own little morning-dew on the outside of the glass."

The shrew touched the beaded cup. "So the glass isn't leaking at all. The cold glass chilled the air around it, and the air dropped its water onto the glass."

"That's the whole craft," Dew said. "Water appearing 'from nowhere' — dew, fog, a sweating glass, mist on a mirror — is always the same thing: air cooled past what it can hold, letting its invisible water out onto a cool surface. Not leaking, not magic — just the air, wringing out onto the cold."