What describes katabatic winds?

Katabatic winds are specifically defined as cold, dense air that is displaced downward from high terrain, such as mountains or glaciers, as it flows into lower elevations such as valleys. This occurs when the air near the mountain slopes cools significantly, becoming denser than the surrounding air. As this cooled air descends under the influence of gravity, it can pick up speed, especially in confined valleys, creating a wind that is often cold and can lead to significant temperature drops in the affected areas.

This phenomenon is commonly observed in polar regions and in mountainous areas where the conditions are appropriate for such downward airflow of chilled air. The cooling typically results from factors like radiational cooling at night or during winter months, when the ground loses heat rapidly.

The other options describe different meteorological phenomena or concepts not related to katabatic winds. For instance, warm winds that rise from valleys refer to thermals or other upward-moving air caused by heating rather than cooling. Winds generated by sea temperature correlate with sea breezes or trade winds influenced by the temperature of ocean water. Lastly, stable winds flowing in one direction describe a different atmospheric condition, often related to prevailing winds or certain weather patterns, neither of which aligns with the nature of katabatic winds.