It is counterclockwise in the northern hemisphere and clockwise in the southern hemisphere. In the northern hemisphere, objects moving in the north-south direction will lean to the right, which is influenced by the geostrophic bias.
When an object moves relative to the earth's surface, it will be influenced by a force called geostrophic deflection force and change its direction, but the geostrophic deflection force is not a real force, but an inertial force. The geostrophic force is a force that cannot be ignored for aerospace. The geostrophic force is the most significant in the polar regions, and gradually weakens towards the equator until it disappears at the equator. And it is very small in daily life and can be ignored.
The geostrophic force of the extended data deflects the wind from south to north in the northern hemisphere to the east, and from north to south to the west, and vice versa in the southern hemisphere. The same is true of missiles.
The influence of geostrophic deviation on ocean currents is similar to that of wind. Generally, the trend of warm current is from low latitude to high latitude, and that of cold current is from high latitude to low latitude. In addition to being blocked by land, the trend of warm current will change, and it will also be affected by geostrophic bias, which will make the ocean current in the northern hemisphere move eastward and the cold current move westward. For example, Britain is located in the northeast of the Atlantic Ocean, which makes Britain warm and humid all the year round.
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