IV.

Modern Cartography

The old cartography flowered after the invention of the printing press. For centuries cartographers created maps on paper. The methods with which they created the image to be printed evolved from engraving on stone and copper to scribing on plastic and the creation of “colour masks” by sophisticated photographic techniques.

In recent decades, and especially since 1990, the situation has changed radically. This has come about through the introduction of the computer into map-making. The earliest work seems to have been carried out by meteorologists and biologists in Sweden, Britain, and the United States. But the vital cartographic work was carried out in a British research group, the Experimental Cartography Unit, in the period from 1968 to 1973, by researchers in Harvard University at about the same time, and thereafter by many others throughout the world. Today virtually all maps, for whatever output medium, are compiled on a computer from data collected and stored in digital format.

Several significant changes came out of all the research, which have transformed cartography for ever. These are that:

• Maps are one (very important) but by no means the only product from computer databases. The computer is no longer used simply to automate traditional cartographic drawing skills, but has become an engine for checking the quality of data, linking data together, searching to find material of interest, and portraying the results in any way the user desires.
• Customization of the results is normal. Maps can be requested, viewed, and downloaded online on demand.
• Virtual maps are commonplace. Such maps produced on a computer screen may never be printed out in paper form.
• Data and computer programs to make such maps are readily available. As a result, there are now far more maps made than ever before, often by people who are not trained cartographers.

The definition of maps has expanded to include new types in addition to the conventional “line map” style. Geometric correction to aerial photography and satellite imagery is now mathematically completed by computer; high-resolution aerial photography world coverage is increasingly obtainable; digital elevation model data is available at global and local resolutions. As a consequence, “photomaps”, “hybrids”, and pseudo 3-D images are now called “maps”. These provide excellent coverage where no maps exist, current maps are not up to date, or for types of landscapes where access is awkward (for example, wetlands). MS Virtual Earth and Google Earth provide free access to imagery of the world for viewing in both 2- and pseudo 3-dimensions while in-vehicle navigation systems now use oblique map views.

Many of the national mapping agencies of governments around the world recognized the effects of technology change and adapted to it. The pioneers including the mapping agencies in Britain, Sweden, Australia, New Zealand, France, the United States, and Canada now run fully operational digital systems and positively promote development of creative new map applications.