High-pressure area High-pressure area A high-pressure area, high or anticyclone is a region where the atmospheric pressure at the surface of the planet is greater than its surrounding environment. Winds within high-pressure areas flow outward from the higher pressure areas near their centers towards the lower pressure areas further from their centers. Gravity adds to the forces causing this general movement, because the higher pressure compresses the column of air near the center of the area into greater density – and so greater weight compared to lower pressure, lower density, and lower weight of the air outside the center. However, because the
Intrapleural pressure Intrapleural pressure In physiology, intrapleural pressure (also called intrathoracic pressure) refers to the pressure within the pleural cavity. Normally, the pressure within the pleural cavity is slightly less than the atmospheric pressure, in what is known as "negative pressure". When the pleural cavity is damaged/ruptured and the intrapleural pressure becomes equal to or exceeds the atmospheric pressure, pneumothorax may ensue. Intrapleural pressure depends on the ventilation phase, atmospheric pressure, and the volume of the intrapleural cavity. At rest we have a negative intrapleural pressure. This gives us a transpulmonary pressure expanding the lungs. Intrapleural pressure is sub-atmospheric. This is due