THE INTERFACE EFFECT AND THE FORMATION OF A LOW-LEVEL JET ALONG THE EAST SIDE OF THE ROCKY MOUNTAINS
Zhou JunNanjing Institute of Meteorology, Nanjing Walter K. Henry Texas A & M University, College Station, TX 77843-3146 U.S.A.
Based upon the analysis of several different causes for the low-level jet along the east side of the Rocky Mountains, the concept of "Interface Effect" is established. The basic mechanism for the formation of the low-level jet in North America has been found to be the compression and divergence, under the driving of ageostrophic winds, of the air columns between two surfaces-the ground and the bottom of inversion-which slope with different patterns in a cross-section normal to the jet stream. As a result, the air parcel is accelerated along the streamline and the anticyclonic shear of the current increased. Also, the diurnal variation of the jet is determined by the interface effect.