isobaric surface

physics

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June 29, 2026

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An isobaric surface is a surface where the barometric pressure is the same at all points. These surfaces are crucial in weather forecasting because they are closely linked to weather patterns.12

On a weather map, isobars are lines connecting points of equal barometric pressure drawn on a reference surface. Meteorologists primarily use sea-level pressure patterns. Regions of low pressure at sea level often indicate bad weather, particularly in winter.2

Wind generally flows parallel to isobars. In the Northern Hemisphere, low pressure is to the left of the wind's direction, while in the Southern Hemisphere, it's to the right. Tightly spaced isobars signify stronger winds.2

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ocean current
Pressure gradients
…surfaces of equal pressure, called isobaric surfaces, are tilted in the deeper layers by the same amount as the sea surface. This is referred to as the barotropic field of mass. The unchanged pressure gradient gives rise to a current speed independent of depth. The oceans of the world, however,…
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…surfaces of equal pressure, called isobaric surfaces, are tilted in the deeper layers by the same amount as the sea surface. This is referred to as the barotropic field of mass. The unchanged pressure gradient gives rise to a current speed independent of depth. The oceans of the world, however,…
Read More