Low-pressure area Low-pressure area A low-pressure area, low, depression or cyclone is a region on the topographic map where the atmospheric pressure is lower than that of surrounding locations. Low-pressure systems form under areas of wind divergence that occur in the upper levels of the troposphere. The formation process of a low-pressure area is known as cyclogenesis. Within the field of meteorology, atmospheric divergence aloft occurs in two areas. The first area is on the east side of upper troughs, which form half of a Rossby wave within the Westerlies (a trough with large wavelength that extends through the troposphere). A second
Intrapleural pressure effects - 1.) mullers maneuver -forced inspiration against a closed glottis results in negative pressure... 2.) Deep inspiration Pathological effects : 1.) Emphysema 2.) Pneumothorax Condition. 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