Geography Education
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If the Earth Stood Still

If the Earth Stood Still | Geography Education |

"The following is not a futuristic scenario. It is not science fiction. It is a demonstration of the results of an extremely unlikely, yet intellectually fascinating query: What would happen if the earth stopped spinning?  ArcGIS was used to perform complex raster analysis and volumetric computations and generate maps that visualize these results.

Seth Dixon's insight:

I love a good "what if?" question and this one (including the GIS model-based analysis) is fascinating. 

Tracey M Benson's curator insight, April 4, 4:49 PM

What a fascinating question, answered as a visualisation: What would happen if the earth stopped spinning? ArcGIS was used to perform complex raster analysis and volumetric computations and generate maps that visualise the results.

Christian Allié's curator insight, April 5, 4:40 AM



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Most scientists agree that the solar day (related to the speed of rotation) is continuously getting longer. This minimal increase of the day length is due mainly to the oceanic tidal friction. When the estimated rate of the slowdown was projected back to past geologic eons, it showed that the length of a day was several hours shorter than today.

Consequently, during the Devonian period (400 million years ago), the earth rotated about 40 more times during one revolution around the sun than it does now. Because the continents have drifted significantly since that time, it is difficult to make estimates of the land versus ocean outlines for that era. However, we can be certain that—with a faster spinning speed in the past—the equatorial bulge of oceanic water was much larger then than it is today. Similarly, the ellipsoidal flattening of the earth was also more significant.

The influence of the rate of the earth's rotation has a dominant effect on the geometry of the globe, in terms of the globe's overall shape as well as the outline of the global ocean. The earth's physical relief is only a secondary factor controlling the delineation of oceans. The slowdown of earth's rotation will continue for 4 billion years—as long as we can imagine. The slowdown infinitesimally—but steadily—changes the globe's geometry and makes it dynamic. The net result of these dynamic adjustments is that the earth is slowly becoming more and more like a sphere. However, it will take billions of years before the earth stops spinning, and the gravitational equipotential creates a mean sea level that is a perfect sphere.


About the Author

Witold Fraczek is a longtime employee of Esri who currently works in the Application Prototype Lab. He received his doctorate in the application of GIS in forestry from Agricultural University and master's degrees in hydrology from the University of Warsaw, Poland, and remote sensing from the University of Wisconsin, Madison.

Melissa Marshall's curator insight, April 9, 10:25 PM

How interesting! The detailed GIS is fascinating and although an unlikely scenario, is great for discussion and deeper thought. You could discuss with students how the world would cope or what sort of device could start it spinning again...?

Geography Education
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Curated by Seth Dixon