Raindrops are a type of precipitation that fall from the atmosphere to the earth’s surface. They are usually spherical in shape and have a diameter of about 0.5 to 5 mm (0.02 to 0.2 inches). The average rainfall rate is around 1,000 mm (39 inches) per year, which means that there are approximately 4 trillion raindrops falling on the earth every day!
The size of raindrops depends on the amount of water vapor present in the air and the temperature of the air. Warm air can hold more water vapor than cold air, so raindrops tend to be larger in warm weather conditions. When the temperature is very cold, snowflakes form instead of raindrops.
Raindrops form when tiny water droplets in clouds combine together to become too heavy to stay airborne. These droplets collide with other droplets and grow in size until they eventually fall from the cloud as precipitation.
The journey from cloud to ground takes anywhere from 10 minutes to 2 hours, depending on the height of the clouds and wind speed. Once a raindrop reaches the ground, it may bounce off or roll along before coming to rest. Some may even evaporate before hitting the ground if they pass through a layer of dry air on their way down!
A single raindrop alone is too small to cause much impact, but when trillions of them fall all at once, they can create some spectacular effects! Heavy rains can lead to flooding, landslides, and even sinkholes as all that water saturates into the ground. On a smaller scale though, rainfall is essential for plant life as it provides them with much-needed moisture for growth.