The correct Answer is Katabatic Wind : Cool air draining from high plateaus
Explanation
Local winds are atmospheric movements that occur over a limited geographical area and are influenced by local topography and temperature differences. These winds often exhibit diurnal or seasonal patterns.
Statement-wise Analysis
- Valley Breeze : Night time, downslope
Incorrect. A valley breeze occurs during the daytime. As the sun heats the valley slopes, the air above them becomes warmer and less dense, rising upslope. This creates a pressure gradient that draws air from the valley floor upwards. Therefore, a valley breeze is a daytime, upslope wind. - Mountain Wind : Day time, upslope
Incorrect. A mountain wind (also known as a mountain breeze or katabatic wind in this context) occurs during the nighttime. As mountain slopes cool rapidly after sunset, the air above them becomes denser and flows downslope into the valley. Therefore, a mountain wind is a nighttime, downslope wind. - Katabatic Wind : Cool air draining from high plateaus
Correct. Katabatic winds are downslope winds that carry high-density, cold air from higher elevations down a slope under the force of gravity. This phenomenon is common in areas with high plateaus or ice sheets where air cools significantly and then flows downwards. - Sea Breeze : Night time, land to sea
Incorrect. A sea breeze occurs during the daytime. Land heats up faster than the sea, causing the air above the land to rise and creating a low-pressure area. Cooler, denser air from the sea then flows towards the land to replace the rising air. Therefore, a sea breeze is a daytime wind blowing from sea to land. The nighttime equivalent, blowing from land to sea, is called a land breeze.
Key Takeaway
Local winds like valley/mountain breezes, sea/land breezes, and katabatic winds are driven by differential heating and cooling of land and water or topographical features, resulting in distinct diurnal patterns and flow directions.