Okay kiddo, have you ever seen a ship in the water before? Well, a weather ship is just like a regular ship, but it's used to measure and study the weather in the ocean.
Instead of carrying people or lots of cargo, a weather ship is filled with special tools and instruments called sensors. These sensors measure things like the temperature of the water, the direction and speed of the wind, and how high the waves are.
The people on the weather ship use these measurements to learn more about the weather patterns in that area of the ocean. They can also use this information to help forecast what the weather will be like in other parts of the world.
So, just like you might use a thermometer to check how hot it is outside or an anemometer to see how fast the wind is blowing, scientists use a weather ship and its sensors to understand the weather and how it affects our planet.