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Motivation is a photography blog that discusses the creative aspects of photography. The posts will include thoughts about images and their interpretation, photographers and their work, technique, workflow, my ongoing projects, and perhaps even the occasional off topic rant.

Death Valley Rivulets

Death Valley is hot, though I have to admit that it was rather pleasant during the workshop I recently attended there, with daytime temperatures often in the 80s.  In fact, it was a welcome break from the sub-zero temperatures that we have been experiencing in Western Pennsylvania. The summer, however, would be a different story.

The reason for the extreme heat in this region which is the lowest point in North America (up to approximately 250 feet below sea level in some portions) is explained in these paragraphs from Wikipedia:

"As a general rule, lower altitudes tend to have higher temperatures. When the sun heats the ground, that heat is then radiated upward, but the air is trapped by the surrounding elevation and the fact that it is denser than the air above it. The atmospheric pressure is higher at very low altitudes than it is under the same conditions at sea level, so the air becomes denser and therefore doesn't rise. This traps the heat near the ground, and also creates wind currents that circulate very hot air, thereby distributing the heat to all areas, regardless of shade and other factors.

This process is especially important in Death Valley as it provides its specific climate and geography. The valley is surrounded by mountains, while its surface is mostly flat and devoid of plants, and so a high percentage of the sun's heat can reach the ground, absorbed by soil and rock. When air at ground level is heated, it begins to rise, moving up past steep, high mountain ranges, which then cools slightly, sinking back down towards the valley more compressed. This air is then reheated by the sun to a higher temperature, moving up the mountain again, whereby the air moves up and down in a circular motion in cycles, similar to how a convection oven works. This superheated air increases ground temperature markedly, forming the hot wind currents that are trapped by atmospheric pressure and mountains, thus stays mostly within the valley. Such hot wind currents contribute to perpetual drought-like conditions in Death Valley and prevent much cloud formation from passing through the confines of the valley, where precipitation is often in the form of a virga. Death Valley holds temperature records because it has an unusually high number of factors that lead to high atmospheric temperatures."

How hot can it get there? Well, Death Valley currently holds the record for having the hottest temperature ever recorded on Earth at 134 degrees Fahrenheit on July 10, 1913. It is also, needless to say, quite dry. But it does rain on occasion, with an average annual rainfall of 2.36 inches according to Wikipedia. We were lucky enough to have some rain a few days before we arrived.  When that happens you can find small rivulets of water on the dried flat ground such as seen here at Salt Creek.  These rivulets flow through salt flats that actually crunch under your boots as you walk on them. In the early morning one can see reflections of the sky and mountains in these small streams of water, most of which you can easily step over.

I revisited this area two days after I took this photograph and the rivulets were all but gone.  It was a privilege to see and photograph them.

Rivulets on Death Valley salt flats after rain © Howard Grill

by Howard G

© Howard Grill