Pressure system the troposphere. In general, subsidence will dry out an air mass by adiabatic or compressional heating. Thus, high pressure typically brings clear skies. During the day, since no clouds are present to reflect sunlight, there is more incoming shortwave solar radiation and temperatures rise. At night, the absence of clouds means that outgoing longwave radiation (i.e. heat energy from the surface) is not absorbed, giving cooler diurnal low temperatures in all seasons. When surface winds become light, the subsidence produced directly under a high-pressure system can lead to a buildup of particulates in urban areas under the ridge, leading to
Low pressure molding Low pressure molding Low Pressure Molding (LPM) with polyamide and polyolefin (hot-melt) materials is a process typically used to encapsulate and environmentally protect electronic components (such as circuit boards). The purpose is to protect electronics against moisture, dust dirt and vibration. Low Pressure Molding is also used for sealing connectors and molding grommets and strain reliefs. Key to this process are the raw materials and specialized molding equipment. Dimer acid based polyamide materials, better known as hot-melts, are used as molding compounds. They are thermoplastics i.e. the material, when heated, becomes less viscous and is able to re-shaped, then hardens