The electrical structure of an inversion

✍ Scribed by R. F. Chisnell; J. Latham; P. Ryder; I. M. Stromberg

• Publisher: John Wiley and Sons
• Year: 1977
• Tongue: English
• Weight: 536 KB
• Volume: 103
• Category: Article
• ISSN: 0035-9009
• DOI: 10.1002/qj.49710343808

✦ Synopsis

Abstract

Measurements were made, using an instrumented aircraft, of the vertical electric field strength, E, and the ionic conductivity, λ, of the atmosphere in the vicinity of a temperature inversion. It was found—moving downwards through the inversion — that the reduction in λ associated with ionic immobilization upon aerosol particles occurred over an appreciably shorter vertical distance than the accompanying increase in E. the ionic current density was not preserved over the region of changing E. These observations suggested that some of the space‐charge created in the region of conductivity gradient was being transported downwards by eddy diffusion. A theoretical model of this process was constructed, based on the principle of current continuity. Excellent agreement between the particularly simple field structure measured on one flight and the theoretical structure existed if the characteristic diffusion length was about 60 m. This corresponds to an eddy diffusion coefficient, K, of about 3.0 m^2^s^−1^.

It is suggested that in some circumstances, the simultaneous measurement of E and λ affords a quantitative technique for the determination of K.