Atmospheric tension refers to the pressure exerted by the weight of air in the atmosphere. This pressure is caused by the gravitational pull of the Earth on air molecules, which creates a force that pushes down on everything at the surface. Atmospheric tension decreases with altitude, meaning that higher elevations experience lower pressure. This concept is crucial for understanding weather patterns and phenomena such as storms and wind. It also plays a significant role in aviation, as pilots must account for changes in atmospheric tension when flying at different altitudes.