Rain is the primary source of most of the fresh water in the world. It plays an important role for life on Earth as part of the hydrologic cycle. When the moisture from the oceans evaporates into the sky, condenses into droplets, and precipitates from the sky over the Earth’s surface, water is distributed throughout the globe. It is thanks to this form of precipitation that we have suitable conditions for diverse ecosystems, power sources, and crop irrigation.
All plants need at least some water to survive, and rain is the most effective means of watering. A regular watering pattern is vital to healthy plants. Too little or too much rainfall can be detrimental, or even devastating to crops. A drought can be drastic, killing numerous crops, while extremely wet weather can cause disease and fungus. Some plants, such as cacti, are able to thrive in areas with limited precipitation. Tropical plants, however, need hundreds of inches of rain per year to survive.
Excessive rain, especially in the wake of long dry spells that harden the soil such that it cannot absorb water, can cause flooding. Many people find the scent of the rain — during, or immediately after a storm — pleasing and distinctive. The source of this scent is the oils produced by plants which are released first into rocks or soil, and later into the air during rainfall.