Why is the salinity lower in the Northern Hemisphere than in the Southern Hemisphere

There are several reasons for this:

1. The land area of the northern hemisphere is much larger than that of the southern hemisphere, so the amount of onshore runoff injection is more. It has a stronger dilution effect on seawater than in the southern hemisphere.

2. The freezing process of the Antarctic continent solidifies the fresh water in the seawater of the surrounding sea area. So the salt content is higher.

3. The northern hemisphere has a larger population, so it has a larger intake of salt in the ocean. (Of course, this reason takes a long time, which should be considered a secondary reason).

First of all, the land area of the Northern Hemisphere is relatively larger than that of the Southern Hemisphere, and then there are more abundant rivers (outflow rivers) in the Northern Hemisphere, indicating that the salinity of the Northern Hemisphere, which is relatively rich in freshwater resources, is lower. In general, this is due to the fact that the water cycle in the Northern Hemisphere (especially the land and sea circulation) is more vigorous and intense than that in the Southern Hemisphere.

The salinity of seawater depends on the amount of evaporation and recharge, and the amount of evaporation in the high latitudes of the northern and southern hemispheres is basically the same.

In the high latitudes of the Northern Hemisphere, many rivers inject fresh water into the ocean, but very little in the Southern Hemisphere, so the salinity of the high latitudes of the Northern Hemisphere is less than that of the Southern Hemisphere.

When summarizing the distribution of seawater salinity, the main factor affecting salinity is evaporation.

and precipitation, there are other factors. In some inland sea areas, because they are far from the ocean, they have a strong personality, and their geographical environment is different, and their personality characteristics are also very different, such as the Red Sea and the Baltic Sea.

Salinity of the sea area. Cause: mid- and high-latitude sea area.

Lower "Baltic 1%)

Reduced evaporation.

Rivers flow in large quantities of fresh water.

Subtropical sea area.

High Red Sea has little precipitation.

Evaporation is greater than precipitation.

Sea area near the equator.

Slightly lower precipitation is abundant.

Precipitation is greater than evaporation.

In addition, the salinity curve implies asymmetry, and the reasons for the asymmetry should be analyzed from the factors affecting salinity. Such as 60°N near the ocean surface and 60°S attached.

Comparison of salinity of near-ocean seawater. The analysis is as follows:

The annual recharge of rainwater in the sea area near 60°N is greater than that in the sea area near 60°S, so that the seawater near 60°N is greatly diluted. This is mainly:

Due to the vast land area of the Northern Hemisphere, the contrast between land and sea is significant, there is more frontal rain, and the North Atlantic Warm Current and the North Pacific Warm Current warm the westerly winds.

Humidification, westerly winds are blocked by the land and uplifted, forming rainfall; The Southern Hemisphere has less land, and the vicinity of 60°s is almost vast oceanic, with precipitation.

Therefore, the annual precipitation in the waters near 60°N is greater than that in the waters near 60°S.

Secondly, the waters near 60°S are much larger than those near 60°N, and there is no injection of terrestrial freshwater. The waters around 60°N are smaller and have a large number of them.

of terrestrial water (river water) is injected, resulting in a greater dilution of the waters around 60°N.