A hyetograph is a
graphical representation
Graphic communication as the name suggests is communication using graphic elements. These elements include symbols such as glyphs and icons, images such as drawings and photographs, and can include the passive contributions of substrate, colour ...
of the distribution of
rainfall
Rain is water droplets that have condensed from atmospheric water vapor and then fall under gravity. Rain is a major component of the water cycle and is responsible for depositing most of the fresh water on the Earth. It provides water f ...
intensity over time. For instance, in the 24-hour rainfall distributions as developed by the Soil Conservation Service (now the NRCS or
National Resources Conservation Service
Natural Resources Conservation Service (NRCS), formerly known as the Soil Conservation Service (SCS), is an agency of the United States Department of Agriculture (USDA) that provides technical assistance to farmers and other private landowners and ...
), rainfall intensity progressively increases until it reaches a maximum and then gradually decreases. Where this maximum occurs and how fast the maximum is reached is what differentiates one distribution from another. One important aspect to understand is that the distributions are for design storms, not necessarily actual storms. In other words, a real storm may not behave in this same fashion. The maximum intensity may not be reached as uniformly as shown in the SCS hyetographs.
See also
*
Voronoi diagram
In mathematics, a Voronoi diagram is a partition of a plane into regions close to each of a given set of objects. In the simplest case, these objects are just finitely many points in the plane (called seeds, sites, or generators). For each seed th ...
- a method adaptable for calculating the average precipitation over an area
External links
Precipitation Maps for USA
Hydrology
{{Hydrology-stub