What typically determines upper winds?

The distinction of upper winds is predominantly influenced by the thermal gradient resulting from temperature differences in the atmosphere. When there are significant variations in temperature between different layers or regions, it leads to differences in air density and pressure, which in turn affects the movement of air. Warmer air is typically less dense and rises, while cooler air is denser and sinks. This process sets up a circulation pattern that manifests as wind at different altitudes.

In the upper atmosphere, especially in the tropopause and stratosphere, the thermal gradient plays a crucial role in establishing jet streams and other high-altitude wind patterns. These currents can dramatically influence weather systems and their behavior, such as storm tracks and the movement of cold and warm fronts. Understanding how temperature differences create these wind patterns is essential for weather prediction and analyzing air travel efficiency.

While local geographical features, altitude, and seasonal changes do have impacts on local and surface winds, they are not the primary drivers of upper wind phenomena.