Seasonal variation of the turbopause: One year of turbulence investigation at 69°N by the joint University of Tromsø/ University of Saskatchewan MF radar

Abstract

Following upgrades to the University of Tromsø/Universiry of Saskatchewan MF radar, located in northern Norway at 69°N, 19°E, we have been able to complete a full calendar year of estimates of mesospheric turbulent intensity. The results represent the first such study using continuous measurements from this region, and temporal and height variations are satisfyingly in accordance with expectation. Since in the past there has been a degree of disagreement as to absolute intensities, we briefly compare our results with some from totally independent methods. The resulting dissipation rates, to be regarded as maxima for the turbulent dissipation, are used to identify an upper limit to the turbopause. The Arctic turbopause appears to exhibit an annual variation, being lower in the summer, in agreement with Danilov et al. [1979] but refuting Blum and Schuchard [1978]. Copyright 1998 by the American Geophysical Union.