Humidity is the water vapour content in the atmosphere.3 forms of humidity are:
Absolute Humidity
The amount of water vapour in the air e.g 6grams in a cubic metre of air.
Specific Humidity(Mixing Ratio)
The mass of water vapour contained in a unit mass of dry air.Formula:mass of water vapour in grams/mass of dry air in kg,expressed as g/kg.
Relative humidity
The amount of water vapour present in the air to its potential water vapour capacity at a given temperature (saturated air=100% relative humidity).Warm air is able to hold more water vapour than cold air thus:
Temperature RISE=more water vapour needed=FALL in relative humidity
Temperature FALL=less water vapour needed=RISE in relative humidity
