请解释一下风是由什么产生的？并用不超过200字的篇幅，以markdown的形式撰写这段解释。请确保文中提及“太阳”、“温度差异”、“空气密度”、“流动”等关键词。
user
Wind is generated by a series of interconnected factors primarily revolving around the sun, temperature differences, air density, and the resultant movement of air masses. The sun heats the Earth's surface unevenly, leading to areas with varying temperatures. Warm regions have higher temperatures, causing the air to expand and become less dense, while cooler areas have denser air. This temperature difference and the subsequent difference in air density create a pressure gradient, which forces air to move from high-pressure areas (where the air is cooler and denser) to low-pressure areas (where the air is warmer and less dense). This movement of air is what we perceive as wind.
assistant