The Role of Shearwise and Transverse Quasigeostrophic Vertical Motions in the Midlatitude Cyclone Life Cycle

Martin, Jonathan E.
April 2006
Monthly Weather Review;Apr2006, Vol. 134 Issue 4, p1174
Academic Journal
The total quasigeostrophic (QG) vertical motion field is partitioned into transverse and shearwise couplets oriented parallel to, and along, the geostrophic vertical shear, respectively. The physical role played by each of these components of vertical motion in the midlatitude cyclone life cycle is then illustrated by examination of the life cycles of two recently observed cyclones. The analysis suggests that the origin and subsequent intensification of the lower-tropospheric cyclone responds predominantly to column stretching associated with the updraft portion of the shearwise QG vertical motion, which displays a single, dominant, middle-tropospheric couplet at all stages of the cyclone life cycle. The transverse QG omega, associated with the cyclones’ frontal zones, appears only after those frontal zones have been established. The absence of transverse ascent maxima and associated column stretching in the vicinity of the surface cyclone center suggests that the transverse ω plays little role in the initial development stage of the storms examined here. Near the end of the mature stage of the life cycle, however, in what appears to be a characteristic distribution, a transverse ascent maximum along the western edge of the warm frontal zone becomes superimposed with the shearwise ascent maximum that fuels continued cyclogenesis. It is suggested that use of the shearwise/transverse diagnostic approach may provide new and/or supporting insight regarding a number of synoptic processes including the development of upper-level jet/front systems and the nature of the physical distinction between type A and type B cyclogenesis events.


Related Articles

  • AFTER-STORM THOUGHTS. Buckley Jr., WM. F. // National Review;11/15/1985, Vol. 37 Issue 22, p63 

    Reports on the effect of hurricane Gloria on the United States. States affected by the hurricane; Other natural calamities that affect the country; Strength of the hurricane; Environmental impact of the hurricane.

  • Cyclone Surges Smaller than Expected.  // Australasian Science;Jan/Feb2005, Vol. 26 Issue 1, p6 

    Reports on the threat posed by cyclone surges to communities in Queensland according to research conducted at the Cooperative Research Centre for Reef Research. Methodology used in the study; Cyclone behavior incorporated in the research model; Probabilities of maximum destruction resulting...

  • Large-Scale Influences on the Evolution of Winter Subtropical Maritime Cyclones Affecting Australia's East Coast. Browning, Stuart A.; Goodwin, Ian D. // Monthly Weather Review;Jul2013, Vol. 141 Issue 7, p2416 

    Subtropical maritime low pressure systems frequently impact Australia's eastern seaboard. Closed circulation lows in the Tasman Sea region are termed East Coast Cyclones (ECC); they can evolve in a range of climatic environments and have proven most destructive during the late autumn-winter...

  • Ozone Measurements from Eyewall Transects of Two Atlantic Tropical Cyclones. Carsey, Thomas P.; Willoughby, Hugh E. // Monthly Weather Review;Jan2005, Vol. 133 Issue 1, p166 

    Measurements of ozone (O3) concentrations obtained during aircraft eyewall crossings of Tropical Cyclones Floyd (September 1999) and Georges (September 1998) by NOAA P-3 hurricane research aircraft showed marked changes between the intensifying and weakening stages of the storms’ life...

  • Major Numerical Forecast Failures over the Northeast Pacific. McMurdie, Lynn; Mass, Clifford // Weather & Forecasting;Apr2004, Vol. 19 Issue 2, p338 

    Strong North Pacific storms that impact the North American west coast are sometimes poorly predicted in the short term (up to 48 h) by operational models, with cyclone position errors of hundreds of kilometers and central pressure errors of tens of millibars. These major numerical forecast...

  • VERTICAL PRECIPITATION STRUCTURES OF CYCLONES CROSSING THE CASCADES. Medina, Socorro; Sukovich, Ellen; A. Houze Jr., Robert // Bulletin of the American Meteorological Society;Dec2007, Vol. 88 Issue 12, p1888 

    The article focuses on the cyclone structures crossing the Cascade Mountains in Pacific Northwest. A research provides a look at the precipitation structure of storms in this region from an observational insight. Researchers describe radar-observed structures qualifying extratropical cyclone...

  • The Influence of Air—Sea Roughness, Sea Spray, and Storm Translation Speed on Waves in North Atlantic Storms. Weiqing Zhang; Perrie, William // Journal of Physical Oceanography;Apr2008, Vol. 38 Issue 4, p817 

    A coupled atmosphere–wave–sea spray model system is used to evaluate the impact of sea spray and wave drag on storm-generated waves, their height variations, and directional wave spectra in relation to the storm location and translation speed. Results suggest that the decrease or...

  • North Atlantic Hurricanes 1977–99: Surface Hurricane-Force Wind Radii. Bell, Katherine; Sawin Ray, Peter // Monthly Weather Review;May2004, Vol. 132 Issue 5, p1167 

    The Hurricane Research Division (NOAA/AMOL/HRD) flight-level data archive of 1977–99 North Atlantic hurricanes is used to create radial profiles of earth-relative surface wind speeds. Radii of hurricane-force winds are determined directly from these generated profiles. The distributions...

  • African Easterly Waves and Cyclonic Activity over the Eastern Atlantic: Composite and Case Studies. Camara, Moctar; Diedhiou, Arona; Gaye, Amadou // International Journal of Geophysics;2011, p1 

    This study aims to understand the main differences over the African continent and the Eastern Atlantic Ocean between African Easterly Waves (AEWs) associated with Atlantic cyclones (developing AEWs) and non-developing AEWs. A statistical study showed that most of the named cyclones generated...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics