Why are the water temperature and salinity different in different parts of the oceans?

The temperature is different, because the water is heated by the sun’s rays, and the closer to the equator, the higher the temperature, the longer, the lower. The salinity is different because some seas and oceans are connected with many rivers, and salinity decreases, also salinity depends on precipitation, the more there are, the less salinity, and from the proximity to glaciers, salinity also decreases from them.