CLIMATIC CHARTS

are maps of sections of the earth’s surface on which the various components of climate, such as mean annual temperature, barometric pre ure, rainfall, humidity, etc. are indicated. This may be done by coloring the various sections of the chart according to the temperature, pre ure, etc., but the more general method is to draw lines on the chart, connecting places whose individual climatic components are the same. Such lines are called isotherms if they connect points of equal temperature; isobars, if the criterion in oan is barometric pre ure; isoyetose, if the rainfall is being considered; and isonephelic lines if they indicate zones of equal cloudine .