A Rossby Wave is a large-scale wave pattern in the atmosphere that influences weather and climate. These waves are primarily caused by the rotation of the Earth and the variation in temperature between the equator and the poles. They play a crucial role in the movement of air masses and the development of weather systems. Rossby Waves can be observed in the jet stream, which is a fast-flowing air current high in the atmosphere. These waves can lead to significant weather events, such as storms and changes in temperature, by affecting the distribution of heat and moisture across different regions.