Environmental Dynamical Control of Tropical Cyclone Intensity—An Observational Study

Zeng, Zhihua; Wang, Yuqing; Wu, Chun-Chieh
January 2007
Monthly Weather Review;Jan2007, Vol. 135 Issue 1, p38
Academic Journal
The effects of two environmental dynamical factors, namely, the transitional speed and vertical wind shear, on tropical cyclone (TC) intensification, intensity, and lifetime peak intensity were analyzed based on observations in the western North Pacific during 1981–2003. In general, both the fast translation and strong vertical shear are negative to both TC intensification and the lifetime peak intensity. Both the very intense TCs and the TCs with rapid intensification rate are found only to occur in a narrow range of translational speeds between 3 and 8 m s-1, and in relatively weak vertical shear. The overwhelming majority of western North Pacific TCs reach their lifetime peak intensity just prior to recurvature where their environmental steering flow and vertical shear are both weak. The results show that few TCs intensified when they moved faster than 15 m s-1, or when their large-scale environmental vertical shear is larger than 20 m s-1. The intensification rate of TCs is found to increase with decreasing vertical shear while the majority of the weakening storms experience relatively strong vertical shear. Overall, strong vertical shear prohibits rapid intensification and most likely results in the weakening of TCs, similar to the fast storm translation. Based on the statistical analysis, a new empirical maximum potential intensity (MPI) has been developed, which includes the combined negative effect of translational speed and vertical shear as the environmental dynamical control in addition to the positive contribution of SST and the outflow temperature as the thermodynamic control. The new empirical MPI can not only provide more accurate estimation of TC maximum intensity but also better explain the observed behavior of the TC maximum intensity and help explain the thermodynamic and environmental dynamical controls of TC intensity. Implications of the new empirical MPI are discussed.


Related Articles

  • Vertical Wind Shear Associated with Left-Moving Supercells. Bunkers, Matthew J. // Weather & Forecasting;Aug2002, Vol. 17 Issue 4, p845 

    Vertical wind shear parameters are presented for 60 left-moving supercells across the United States, 53 of which produced severe hail (≥1.9 cm). Hodographs corresponding to environments of left-moving supercells have a tendency to be more linear than those of their right-moving supercell...

  • TROPICAL CYCLONE DESTRUCTIVE POTENTIAL BY INTEGRATED KINETIC ENERGY. Powell, Mark D.; Reinhold, Timothy A. // Bulletin of the American Meteorological Society;Apr2007, Vol. 88 Issue 4, p513 

    Tropical cyclone damage potential, as currently defined by the Saffir-Simpson scale and the maximum sustained surface wind speed in the storm, fails to consider the area impact of winds likely to force surge and waves or cause particular levels of damage. Integrated kinetic energy represents a...

  • The Influence of Horizontal Environmental Variability on Numerically Simulated Convective Storms. Part I: Variations in Vertical Shear. Richardson, Yvette P.; Droegemeier, Kelvin K.; Davies-Jones, Robert P. // Monthly Weather Review;Oct2007, Vol. 135 Issue 10, p3429 

    Severe convective storms are typically simulated using either an idealized, horizontally homogeneous environment (i.e., single sounding) or an inhomogeneous environment constructed using numerous types of observations. Representing opposite ends of the spectrum, the former allows for the study...

  • Structure of Highly Sheared Tropical Storm Chantal during CAMEX-4. Heymsfield, G. M.; Halverson, J.; Ritchie, E.; Simpson, Joanne; Molinari, J.; Tian, L. // Journal of the Atmospheric Sciences;Jan2006, Vol. 63 Issue 1, p268 

    Tropical Storm Chantal during August 2001 was a storm that failed to intensify over the few days prior to making landfall on the Yucatan Peninsula. An observational study of Tropical Storm Chantal is presented using a diverse dataset including remote and in situ measurements from the NASA ER-2...

  • A Numerical Study of Hurricane Erin (2001). Part I: Model Verification and Storm Evolution. Liguang Wu; Braun, Scott A.; Halverson, J.; Heymsfield, G. // Journal of the Atmospheric Sciences;Jan2006, Vol. 63 Issue 1, p65 

    The fifth-generation Pennsylvania State University–National Center for Atmospheric Research (PSU–NCAR) Mesoscale Model (MM5) is used to simulate Hurricane Erin (2001) at high resolution (4-km spacing) from its early development as a tropical depression on 7 September 2001, through...

  • High-Resolution Simulation of Hurricane Bonnie (1998). Part I: The Organization of Eyewall Vertical Motion. Braun, Scott A.; Montgomery, Michael T.; Zhaoxia Pu // Journal of the Atmospheric Sciences;Jan2006, Vol. 63 Issue 1, p19 

    The fifth-generation Pennsylvania State University–National Center for Atmospheric Research (PSU–NCAR) Mesoscale Model (MM5) is used to simulate Hurricane Bonnie at high resolution (2-km spacing) in order to examine how vertical wind shear impacts the distribution of vertical...

  • The Interaction of Numerically Simulated Supercells Initiated along Lines. Bluestein, Howard B.; Weisman, Morris L. // Monthly Weather Review;Sep2000, Vol. 128 Issue 9, p3128 

    Supercells in the southern plains are often localized, forming as cells along a convective line, even though the environment may support supercell formation over a much broader, mesoscale region. A set of numerical experiments is devised in which it is demonstrated that the evolution of...

  • Low-Level Mesovortices within Squall Lines and Bow Echoes. Part I: Overview and Dependence on Environmental Shear. Weisman, Morris L.; Trapp, Robert J. // Monthly Weather Review;Nov2003, Vol. 131 Issue 11, p2779 

    This two-part study proposes fundamental explanations of the genesis, structure, and implications of low-level meso-γ-scale vortices within quasi-linear convective systems (QLCSs) such as squall lines and bow echoes. Such “mesovortices” are observed frequently, at times in...

  • Ambient Conditions Associated with the Maintenance and Decay of Quasi-Linear Convective Systems Crossing the Northeastern U.S. Coast. Lombardo, Kelly A.; Colle, Brian A. // Monthly Weather Review;Dec2012, Vol. 140 Issue 12, p3805 

    Quasi-linear convective systems (QLCSs) crossing the Atlantic coastline over the northeastern United States were classified into three categories based on their evolution upon encountering the coast. Composite analyses show that convective lines that decay near the Atlantic coast or slowly decay...


Read the Article


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

Try another library?
Sign out of this library

Other Topics