The solid line indicates the 850 mb pressure level, and points A and B are at the same altitude.

-Suppose the winds aloft are geostrophic and blowing from the north. When isobars at the surface have the same orientation, from which of the following directions is the wind blowing?

Question

The solid line indicates the 850 mb pressure level, and points A and B are at the same altitude.
​
​ 
-Suppose the winds aloft are geostrophic and blowing from the north. When isobars at the surface have the same orientation, from which of the following directions is the wind blowing?

Quizplus · Accepted Answer

The geostrophic wind blows parallel to the isobars and to the right of the direction of the pressure gradient force (in the Northern Hemisphere). Since the 850 mb pressure level is above the surface, the surface pressure and isobars can have the same orientation. Therefore, if the wind is blowing from the north at the 850 mb level, it would be blowing from the northwest at the surface, which is choice D.

The Solid Line Indicates the 850 Mb Pressure Level, and Points