7 December 2014
Chapter 10 #1
Did you know that a water molecule plays a complex role in the earths natural system? The exchange of water and the reservoirs are what make up our hydrological cycle. Water starts out in reservoirs, but never stays there for ever. It travels through the earths systems in an endless cycle changing water from vapor to liquid to a solid physical state. When the sun heats the water from the oceans molecules they rise as a vapor into the air. When the water cools down it becomes a liquid which forms clouds called condensation. Water runs off glaciers and snow turning from a solid state to a liquid after being heated up. After the cool water turns into clouds it creates precipitation which makes the clouds saturated and release water. Depending on the temperature of the weather it can the clouds can release water in the form of either rain, snow, or hail. Water coming from plants leaves as a vapor into the atmosphere which is know as transpiration. When water is moved downward it moves into open spaces in the soil and rock known as infiltration. When this happens it turns into groundwater and can travel to lakes, streams, and oceans. After the water runoffs from rainfall or snowmelt the levels exceed the lands ability to absorb all of it and the rest of the runoff flows the water into rivers and streams to lakes and oceans. This happens again and again everyday and it happens many times throughout the course of one day. Water molecules have such a high heat capacity that it is one of the most important greenhouse gases. As the earth warms, the high rates of evaporation result in an increase of the water vapor content of air. Because of this additional water vapor it leads to the absorption of more heat rising the earths temperature. Clouds, snow, and ice are important roles in the energy balance between the earths surface and atmosphere. These types of objects reflect the light from their surfaces, limiting the amount of heat absorbed by the earth. All of these things are part of what a water molecule does for the earth and what it does in the hydrological cycle.