BAROMETERS

Abstract

Barometers are used to measure atmospheric pressure, using the pressure exerted by the atmosphere by using water, air, or mercury. An aneroid barometer uses air. Pressure tendency can forecast short term changes in the weather. Numerous measurements of air pressure are used within surface weather analysis to help find surface troughs, high pressure systems, and frontal boundaries. Isobars are lines showing areas of equal atmospheric pressure. When marked on a chart they show as acontour map of areas of high and low pressure.