Title: Wind creates most common ocean surface waves
Demo topic: How ocean waves are created

Source URLs:
- NOAA National Ocean Service, "Why does the ocean have waves?": https://oceanservice.noaa.gov/facts/wavesinocean.html
- NOAA Ocean Exploration, "What causes ocean waves?": https://oceanexplorer.noaa.gov/ocean-fact/waves/

Main idea:
Most everyday ocean surface waves are caused by wind. Wind blows across the water, transfers energy to the surface, and creates ripples that can grow into larger waves.

How it starts:
The wind interacts with the water at the ocean surface. Friction and pressure differences disturb the surface and create small ripples. If the wind continues to blow, it can keep adding energy to those ripples.

Why waves grow:
Waves can become larger when:
- the wind is stronger
- the wind blows for a longer time
- the wind blows across a longer stretch of water

That long stretch of open water is often called fetch. Longer fetch gives the wind more room to transfer energy into the water.

Sea vs. swell:
Waves near the storm or wind source can look messy and choppy. Waves that travel away from the source can organize into smoother wave trains called swell.

Key facts:
- Wind is the main cause of ordinary ocean surface waves.
- Wind transfers energy to the water surface.
- Stronger wind, longer wind duration, and longer fetch can all help waves grow.
- Swell can travel away from the area where the wind first created the waves.

Research-report use:
This note should support the main cause section: everyday waves are usually wind-driven.
