under a Creative Commons License. Nonlinear Processes in Geophysics Channelling of high-latitude boundary-layer flow

• Main Authors: N. Nawri, R. E. Stewart
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Cape Dorset; Canadian Archipelago; Iqaluit
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.371.1215; http://hal.archives-ouvertes.fr/docs/00/30/29/52/PDF/npg-15-33-2008.pdf

Abstract. Due to the stability of the boundary-layer stratification, high-latitude winds over complex terrain are strongly affected by blocking and channelling effects. Consequently, at many low-lying communities in the Canadian Archipelago, including Cape Dorset and Iqaluit considered in this study, surface winds for the most part are from two diametrically opposed directions, following the orientation of the elevated terrain. Shifts between the two prevailing wind directions can be sudden and are associated with geostrophic wind directions within a well defined narrow range. To quantitatively investigate the role of large-scale pressure gradients and the quasi-geostrophic overlying flow, an idealised dynamical system for the evolution of channelled surface winds is derived from the basic equations of motion, in which stability of stationary along-channel wind directions is described