Geopotential height

Definition of Geopotential Height

Geopotential height represents a vertical coordinate tied to Earth's mean sea level, a modification to geometric height (elevation above mean sea level). This concept accounts for gravity variation due to changes in latitude and elevation. In simpler terms, it denotes the height above sea level of a pressure level within the atmosphere.

Understanding Geopotential Height

Meteorologists employ the idea of geopotential height to simplify motion equations. The actual gravitational force diminishes with increased height; however, 'geopotential height' serves to regard the atmosphere as though gravity remains constant.

The significance of this concept is evident in the interpretation of atmospheric pressure patterns, particularly in weather prediction. The 500-millibar geopotential height is commonly utilized in these forecasts.

Geopotential Height and Weather Systems

Geopotential height emerges as a key factor in weather forecasting. Weather systems on a large scale, comprising high-pressure and low-pressure systems, align with distinctive geopotential height patterns.

A geopotential height of a high value corresponds to high pressure at that level, generally indicative of clear skies and tranquil weather. Conversely, a lower geopotential height is linked to low pressure, typically leading to stormy weather conditions.

Geopotential Height and Climate

Data related to geopotential height also plays an essential role in climate studies. Changes in the geopotential height field can suggest alterations within the climate system. An example is a sustained increase in the average geopotential height at a certain pressure level, potentially indicating a warming trend.

Measurement of Geopotential Height

Typically, weather balloons equipped with radiosondes measure geopotential height. As these balloons ascend through the atmosphere, radiosondes send back data on temperature, pressure, and humidity. Meteorologists then utilize this data to compute the geopotential height at various pressure levels. In addition, satellites supply invaluable geopotential height data over extensive regions.