Maps: An Integral Part of Meteorology

In the study of meteorology (as well as numerous other branches of "earth sciences"), cartography (map making) plays an important role.  Four elements are common to all types of maps: a title, a legend, a scale, and an orientation (i.e. a compass rose).  The following examples are a variety of maps which prove to be useful in meteorology, with a brief exposition on each.

Chloropleth maps use shaded/ colored regions to symbolically represent the distribution of a variable.  For example, in the map above (taken from Colorado Cartographics LTD.), the estimated household income for the 48 contiguous United States is represented.  Darker-shaded states represent higher income levels, while states which receive a lighter shading denote lower household incomes.  While this map has a proper title, legend, and orientation, it is missing a scale.

"An isopleth map generalizes and simplifies data with a continuous distribution." (http://www.aegis.jsu.edu/mhill/phygeogone/isoplth.html)  This example, taken from the University of Illinois at Urbana-Champaign, is a specific example of an isopleth map call ed an isotherm.  It uses continuous regions of color to denote the surface temperature over the United States and Canada.  A second example of an isopleth map, called a topographical map, illustrates the elevation profile of specific regions.  Topographical lines (often abbreviated as "topo" lines), make such cartography possible.

Topographical rendering of Springer Mountain and surrounding area.  I live here!

Dot density maps are another type of useful cartography.  Dot density maps use the presence of a "dot" or other symbol to represent a variable.  For example, in the following example of a dot density map, the presence of a dot in a region represents the presence of 100,000 people.

Though the map contains no title, scale, or orientation, valuable information can be gleaned from the legend alone.

Similar to the dot density map is the proportional symbol map.  Rather than using a series of one-sized dots to represent a variable (i.e. population), a proportional symbol map uses various sizes of the same symbol to represent a variable.  In the following example, taken from TMap , the 1990 population distribution of Africa is represented.

The last map type which will be shown is the environmental sensitivity map.  NOAA defines an environmental sensitivity index map as one which "provide[s] a concise summary of coastal resources that are at risk if an oil spill occurs nearby."  Various forms of symbols and shading are used to denote the at-risk resources, both human and environmental.

AND, as a bonus, check out Hurricane Emily's movement from 1993 (video provided by GFDL/ NOAA)!

Thanks for reading this first post!

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