What is a dew point, a isobar, and a relative humidity.?
The dew point is the temperature at which air is completely saturated. This can be achieved by rising air, nighttime radiational cooling, or advection. An isobar is a line of equal pressure on a weather map. These are good for locating low and high pressure centers as well as areas of steep pressure gradient. Relative humidity is a percentage of the amount of water vapor in a parcel of air. Relative humidity is calculated by the ratio of vapor pressure and saturation vapor pressure multiplied by 100. Vapor pressure is the measure of the water content in the air. Saturation vapor pressure is the maximum water vapor capacity of the air.
