The distribution of tropospheric velocity divergence with respect to pressure systems

With the aid of an electronic computer, velocity divergence, vertical velocity, and thermal advection computations are performed at the standard pressure levels. These parameters are then related to tropospheric pressure systems, classified according to subsequent development or non-development. Typical plan view and cross section patterns are presented. The writers wish to express their appreciation to Professor George J. Haltiner of the U. S. Naval Postgraduate School for his guidance and assistance in this study. Appreciation is also expressed to the personnel of the U. S. Navy Fleet Numerical Weather Facility for their cooperation during the preparation of this paper. We are especially indebted to CDR. L. C. Clarke and LCDR M. Jane Seljos for their aid and programming assistance.http://www.archive.org/details/distributionoftr00aldeLieutenant, United States Nav

Confirmation of the topology of the Wendelstein 7-X magnetic field to better than 1:100,000

Fusion energy research has in the past 40 years focused primarily on the tokamak concept, but recent advances in plasma theory and computational power have led to renewed interest in stellarators. The largest and most sophisticated stellarator in the world, Wendelstein 7-X (W7-X), has just started operation, with the aim to show that the earlier weaknesses of this concept have been addressed successfully, and that the intrinsic advantages of the concept persist, also at plasma parameters approaching those of a future fusion power plant. Here we show the first physics results, obtained before plasma operation: that the carefully tailored topology of nested magnetic surfaces needed for good confinement is realized, and that the measured deviations are smaller than one part in 100,000. This is a significant step forward in stellarator research, since it shows that the complicated and delicate magnetic topology can be created and verified with the required accuracy