Attached: ------ general quantitative relationship between ambient temperature change and environmental humidity:
In the standard air pressure, pumping a cubic meter of water vapor in the air, weighing its weight can be obtained absolute humidity. It is expressed as the water content of one cubic meter of air (g/m?0?6).
For example, in a general humidity chart data shows the maximum water vapor content in one cubic meter of air at a certain temperature. As the temperature increases, so does the water vapor content of the air. For example, at 10 °C (50 °F), air can contain 9 grams of water vapor. At this point the air is at its maximum absolute humidity, which we call saturation. At 20 °C (68 °F), the air is saturated with 17 g/m?0.6. Therefore, if one cubic meter of air in a sealed container contains 9 grams of water vapor at 20 °C, the saturation level is 9 g/m?0.6 . If 3 grams of water are added to the container, the evaporation of the water increases the absolute humidity of the container to 12 g/m?0.6 . If 8 grams of water are added, 5 grams of water will evaporate and 3 grams of water will remain at the bottom of the container because at 20 degrees Celsius, only 17 grams of water vapor can be contained in one cubic meter of air. When there are only 9 grams of water vapor in the container, the relative humidity of the air in the container is 9/17=53%.
Relative humidity depends on the temperature of the air. If there is no excess water vapor added, the relative humidity will drop as the temperature rises. So, when the container is heated to 25 degrees Celsius, the table shows that one cubic meter of air can contain 23 grams of water vapor at this temperature, and the relative humidity drops: 9/23=39%
If the temperature of the air in the container drops to 15 degrees Celsius, the relative humidity rises even if no more water is added. At 15 degrees Celsius, one cubic meter of air can contain only 12.5 grams of water vapor, so the relative humidity is 9/12.5=72%.
If the air is cooled to 9 degrees Celsius, the water vapor in the container is saturated, and its relative humidity will rise to 100 percent. If the air is cooled further, small water droplets will form on the walls of the container because the air must condense some of the water vapor. The temperature at which condensation of water vapor begins to occur (i.e., the temperature at which the air becomes saturated) is called the dew point. In winter, indoors, the air circulates to the window ledge, where the temperature is low enough that the air can be cooled below its dew point, and water droplets appear on the window.