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How can people turn a river on and off?

On Tennessee’s Ocoee River, a rafting stretch can change dramatically when water is released into the channel. Water used for power generation may instead travel through a flume to a downstream powerhouse. The visible change is a change in routing and flow, not the disappearance of an entire river.

3–7 min

Questions you could explore

  • Where is the water going while the recreational channel has little flow?

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Environment and climate

What can tree rings reveal about past climate?

A tree keeps a record of growth in its wood, but reading that record as climate history takes more than counting rings. Moisture, temperature, and other growing conditions can leave overlapping clues.

4–5 min

What can tree rings reveal about past climate?

Environment and climate4–5 minA tree keeps a record of growth in its wood, but reading that record as climate history takes more than counting rings. Moisture, temperature, and other growing conditions can leave overlapping clues.

Environment and climate

Why can a city be warmer than nearby countryside?

The trip from a leafy edge of town to a dense street can also be a trip between different temperatures. Buildings, pavement, vegetation, and waste heat all affect the balance, and the contrast changes with weather and time of day.

3–5 min

Why can a city be warmer than nearby countryside?

Environment and climate3–5 minThe trip from a leafy edge of town to a dense street can also be a trip between different temperatures. Buildings, pavement, vegetation, and waste heat all affect the balance, and the contrast changes with weather and time of day.

Environment and climate

A trip through a wastewater treatment plant

Water disappearing down a drain begins another journey before it reaches a river or the sea. Uisce Éireann's description of treatment in Ireland separates several different jobs, from screening out objects to biological treatment; the resulting effluent is not drinking water.

4–5 min

A trip through a wastewater treatment plant

Environment and climate4–5 minWater disappearing down a drain begins another journey before it reaches a river or the sea. Uisce Éireann's description of treatment in Ireland separates several different jobs, from screening out objects to biological treatment; the resulting effluent is not drinking water.

How can people turn a river on and off? | Speech Topic | speaking.app