Isolines are lines where the value of a variable
stays constant. In meteorology
, there are many different types of isolines. These isolines are used to analyze weather maps
and to make future forecast
s. Here are some of the many types:
a line of constant pressure
a line of constant temperature
a line of constant dew point temperature
a line of constant height above sea level
When drawing isolines on a map, different colors are used to represent different types. Isobars and Isohypses are black. Isotherms are red, and isodrosotherms are green.
Also there are guidelines to follow when analyzing a map with isolines. They are as follows:
- All data points along an isoline have the same value
- The interval between isolines is a constant value on any one map
- Lower values are always on one side of an isoline while higher values are on the other side.
- Isolines cannot cross or touch.
- Isolines never split.
- Isolines will generally tend to be smooth and parallel.
- Interpolation between points should be as exact as possible
- Do not draw lines where there are no data points.
- If possible, connect isolines of the same value
- Label each open isoline on its ends and each closed isoline in the center.
- Isolines must be drawn so as to separate or include all data points.