Humidity, evaporation, and condensation

At dew point air becomes saturated and vapour starts changing into liquid droplets. Link dew point with condensation.

High temperature and dry wind convert water into vapour faster. For evaporation check both temperature and wind.

Absolute humidity is the amount of water vapour present in a fixed volume of air. Its unit is usually gram per cubic metre.

Condensation begins when air cools to dew point and becomes saturated. In exams remember cooling and saturation together.

Specific humidity tells the mass of water vapour in a mass of air. Distinguish it from absolute humidity.

Saturated air holds maximum water vapour at a given temperature. After this extra vapour may condense.

In evaporation water absorbs latent heat from surroundings and becomes vapour. That is why evaporation can feel cooling.

As temperature rises the water vapour holding capacity of air increases. This is key for understanding relative humidity.

Continuous evaporation from the sea increases water vapour in the air. Nearness to water affects humidity.

Relative humidity of (100%) means air holds water vapour up to its capacity. This increases the chance of condensation.

High relative humidity means air already has much moisture so evaporation slows down. Remember the inverse relation between evaporation and humidity.

Fog forms near the surface when water vapour condenses into tiny droplets. Understand it as a cloud near the ground.

More water vapour slows the evaporation of sweat and makes weather feel sultry. Relative humidity is important for human comfort.

Clouds form from tiny droplets or ice particles through condensation or deposition of water vapour. Treat clouds as a visible form of condensation.

Relative humidity depends on the ratio of actual vapour pressure to saturation vapour pressure. A larger denominator lowers relative humidity.

Both dew and frost form due to a cooled surface. The difference is that frost forms as ice crystals by deposition.

Release of water vapour from plants is called transpiration. It is an important source of atmospheric moisture.

A larger surface gives more contact area for evaporation. Therefore a wide sea can evaporate more than a small pond.

Water vapour is mainly found in the troposphere because weather phenomena occur there. In geography connect weather with the troposphere.

When cooling goes below dew point extra water vapour begins to condense. This may form dew fog or clouds.