Mathematics is used in several areas of knowledge and, where least expected, there it is to try to explain and understand physical, chemical, environmental and social phenomena. The creation of mathematical models to explain these phenomena is of fundamental importance for decision making and the creation of strategies to deal with the most varied situations.
We are daily informed about the weather forecast in the most diverse media. A series of variables is responsible for determining a good weather forecast, among which we can highlight: a atmospheric pressure, temperature, humidity and precipitation, which is the amount of rain in a given period of time. We often do not pay enough attention to these forecasts, but they are of great value for the agricultural sector and for the prevention of tragedies related to landslides and floods.
Knowing the volume of rain in a given region is also very important and the method to calculate this volume is unknown to a large part of the population. The calculation of this volume involves only concepts of spatial and plane geometry.
The pluviometer is a meteorological device designed to measure, in millimeters, the height of the water sheet generated by the rain that fell in an area of 1m2.
Saying that it rained 100 mm in a region means saying that in an area of 1 m2, the sheet of water formed by the rain that fell has a height of 100 millimeters. This volume can be obtained by calculating the volume of the 1 m parallelepiped2 of base area and height of 100 mm = 0.1 meters.
Thus, the volume of rain will be given by:
V = (base area) x height
V = 1 x 0.1 = 0.1 m3
This volume can be determined in liters, remembering that 1 m3 = 1000 liters.
Thus, a rain of 100 mm is equivalent to a volume, in liters, of:
V = 0.1 x 1000 = 100 liters
This implies that, for every square meter in the region, there was a precipitation of 100 liters.
By Marcelo Rigonatto
Specialist in Statistics and Mathematical Modeling
Brazil School Team
Spatial Geometry - Math - Brazil School
Source: Brazil School - https://brasilescola.uol.com.br/matematica/calculo-volume-chuvas.htm