Some rise and some sink what is it?
It causes convection currents because there is hot air and cold air.The hot air will will rise and the cold air will sink. then the cold ari will rise and the hot air will sink. it all changes.For instance, the hot air after it rises will sink down adn become cold air. The cold air after it sinks, it will become hot air and rise.
The higher the saline content in water the heavier the water. This causes it to sink towards the bottom and water with lower levels will rise to the top. It will remain so unless stirred vigoriouly and often. Many animals live, and thrive in this setting, such as salt marshes, springs, also some ponds and lakes.
Well some people will sink because they are very muscular, because muscle has a lower bouyancy than fat- they sink. Some people may not be EXXTREMLY muscular- but if you let the air out of your lungs you will not have as much air to keep you floating upwards like a bubble does, and will in turn sink.