Chaparral rainfall graph

Purpose

The purpose of this lab is to construct and analyze a climograph (also called climatogram), and describe the relationship of the climate (i.e., amount of rainfall and variance of temperature) and the effect of the distribution of biomes globally.

Background

Weather is a local area’s short-term temperature, precipitation, humidity, wind speed, cloud cover, and other physical conditions of the lower atmosphere. Climate, on the other hand, is a geographic area’s pattern of atmospheric or weather conditions over long periods of time. Average temperature and average precipitation are the two main factors determining climate, which are controlled by factors such as latitude (distance from the equator), land/water contrasts (continental and maritime locations have differences in atmospheric heating due to moderating effect of water), ocean currents, wind patterns, and mountains (creates changes in altitude -distance above sea level, and rainshadow effect).

Biomes are large terrestrial regions characterized by similar climate, soil, plants, and animals, regardless of where they are found in the world. Biomes are closely associated with climate. You can easily associate the climate of your own locality with the biome found there. Only by extensive travel, however, can the close relationship of particular climates with particular biomes be learned on a worldwide basis. This exercise is a poor substitute for such travel; but if it is carried out thoughtfully and with frequent reference to the description of biomes in the text, it can help you understand the biological relationships that make up the diversity of the biotic communities found on land.

Below you will find six examples of climographs, grids on which averages of precipitation and temperature at a particular location are plotted together. These climographs show variations in only two important climatic factors during a year. Other factors may greatly affect climate, but a climograph does give a rough idea of climate in the location from which the data were obtained.