Alfred Wegener: Difference between revisions
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That was that. Alfred returned to Lindenberg and went back to work.
=== Clear air turbulence ===
His hopes for a polar adventure dashed. He threw himself back into the scientific question he had begun to pursue in the fall : the cause of the temperature oscillations recorded on the kite thermographs.
The problem Alfred pursued concerned a phenomenon that we are all familiar from airplane travel : the clear air turbulence. "Within the atmosphere," Alfred explained, "when a warmer and therefore lighter layer of air moves across a colder denser layer, waves must form." The idea is that when one layer of a fluid slides over another, the difference in density suppresses mixing, but the difference in velocity encourages it. The mixing is the cause of waves, which draw their energy from the velocity difference between the two layers. If the velocity difference is great enough between the two layers, the waves can even break, creating severe clear air turbulence. Within the atmosphere, the phenomenon is tied to the [[Stratosphere|tropopause]], the boundary between warm layers above and cold layers below. The greater the temperature and velocity differences between the two air layers, the greater the likelihood of mixing and the formation of waves.
Alfred plotted the results of his calculations with the vertical axis showing the temperature difference between the layers and the horizontal axis showing the wind-speed difference. The idea was to provide access to the predicted wavelength at the boundary surface, for any combination of air temperatures and wind speeds. With the graph in hand, the next part of the investigation was to compare temperature observations on kite flights with the theory as embedded in the chart.
However, the observational difficulties were formidable. By the end of February, he had only been able to find three useful records out of nearly fifty flights. Moreover, the agreement between theory and observation was terrible, and error of 25 - 30 percent. It appeared that this required a long series of observations and some intricate correcting, it would last perhaps the rest of the year and certainly the rest of his time at Lindenberg.
They days began to blend into one another. Kurt and Alfred already talked privately about what they were going to do after Lindenberg. Kurt was negotiating (quietly) for a job as assistant at the Physikalischer Verein in Frankfurt. Meanwhile, Alfred was seriously considering making a move at the same time.
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