What Causes Humidity

Humidity is basically an invisible water vapor mixed into the air. In indoor area, there are many causes that create humidity, such as cooking, boiling water, poor ventilation, taking hot shower, human and indoor plant respiration. Human respiration creates humidity when the air passes the mucous membrane as this tissue lined with fluid that transfers the heat and water into the air. Fun fact: an adult typically lose about 200-300 ml of water daily through the evaporation of moisture through normal breathing.

Why tropical countries are more humid?

Because intense solar heat accelerates water evaporation and warm air naturally holds more moisture than cold air. The equator receives direct sunlight year-round. A massive vegetation also do something called transpiration, which pull water from deep soil and sweat it out into the atmosphere.