How is change measured and quantified? For many it is memory based, and the first line starts "I remember when..." and frequently ends with "it is all ruined now". But there are alternatives ways to measure change that are more quantitative and do not rely on the imperfections of memory. One methodology is photographic. Images captured over period of time can be used to document change and are neutral recordings of changes in the landscape.
Below are 2 images of the entrance to Cave Creek Canyon in the Chiricahua Mountains of the Coronado National Forest. The first is a postcard taken in the 1940's, while the second is a photograph taken from the same place on September 18, 2011, a span of 60-70 years.
Note the changes in the entryway, the bronze plaque is missing as is the left stone pillar. Cathedral Rock as well as the other outcrops are the same but an abundance of low scrubby vegetation has grown up obscuring part of the view. But the overall density of vegetation covering the lower slopes appears similar.
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| 1940's view of the entrance to the Coronado National Forest in Cave Creek Canyon | . |
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| The same view taken September 18, 2011. |