Departures from Axisymmetric Balance Dynamics during Secondary Eyewall Formation

Abarca, Sergio F.; Montgomery, Michael T.
October 2014
Journal of the Atmospheric Sciences;Oct2014, Vol. 71 Issue 10, p3723
Academic Journal
Departures from axisymmetric balance dynamics are quantified during a case of secondary eyewall formation. The case occurred in a three-dimensional mesoscale convection-permitting numerical simulation of a tropical cyclone, integrated from an initial weak mesoscale vortex in an idealized quiescent environment. The simulation exhibits a canonical eyewall replacement cycle. Departures from balance dynamics are quantified by comparing the azimuthally averaged secondary circulation and corresponding tangential wind tendencies of the mesoscale integration with those diagnosed as the axisymmetric balanced response of a vortex subject to diabatic and tangential momentum forcing. Balance dynamics is defined here, following the tropical cyclone literature, as those processes that maintain a vortex in axisymmetric thermal wind balance. The dynamical and thermodynamical fields needed to characterize the background vortex for the Sawyer-Eliassen inversion are obtained by azimuthally averaging the relevant quantities in the mesoscale integration and by computing their corresponding balanced fields. Substantial differences between azimuthal averages and their homologous balance-derived fields are found in the boundary layer. These differences illustrate the inappropriateness of the balance assumption in this region of the vortex (where the secondary eyewall tangential wind maximum emerges). Although the balance model does broadly capture the sense of the forced transverse (overturning) circulation, the balance model is shown to significantly underestimate the inflow in the boundary layer. This difference translates to unexpected qualitative differences in the tangential wind tendency. The main finding is that balance dynamics does not capture the tangential wind spinup during the simulated secondary eyewall formation event.


Related Articles

  • Varied pathways for simulated tropical cyclone rapid intensification. Part II: Vertical motion and cloud populations. Harnos, Daniel S.; Nesbitt, Stephen W. // Quarterly Journal of the Royal Meteorological Society;Apr2016, Vol. 142 Issue 697, p1832 

    Differences in the vertical velocity characteristics associated with various cloud populations are evaluated for two simulated cases of tropical cyclone (TC) rapid intensification (RI) under varying wind shear. Within the radius of maximum wind (RMW), preceding RI in the low-shear TC (hurricane...

  • Varied pathways for simulated tropical cyclone rapid intensification. Part I: Precipitation and environment. Harnos, Daniel S.; Nesbitt, Stephen W. // Quarterly Journal of the Royal Meteorological Society;Apr2016, Vol. 142 Issue 697, p1816 

    Two 1-km Weather Research and Forecasting model simulations of the rapid intensification (RI) periods of hurricanes Ike (2008) and Earl (2010), under low and high wind shear respectively, are performed to evaluate mechanisms linked to the initiation and maintenance of RI. Despite similar...

  • Robust Observational Quantification of the Contribution of Mesoscale Convective Systems to Rainfall in the Tropics. Roca, R.; Aublanc, J.; Chambon, P.; Fiolleau, T.; Viltard, N. // Journal of Climate;Jul2014, Vol. 27 Issue 13, p4952 

    Satellite estimation of precipitation and satellite-derived statistics of mesoscale convective systems (MCS) are analyzed conjunctively to quantify the contribution of the various types of MCS to the water budget of the tropics. This study focuses on two main mesoscale characteristics of the...

  • Developing an MCS index using the climatology of South America. Rasera, Gustavo; Anabor, Vagner; Scremin Puhales, Franciano; Dal Piva, Everson // Meteorological Applications;Jul2018, Vol. 25 Issue 3, p394 

    ABSTRACT: Even though mesoscale convective systems (MCS) are of great importance in precipitation regimes besides being related to severe weather events, they are still not easy to predict. This study builds an objective index for South American MCS based on synoptic features present before the...

  • The Impact of Incongruous Lake Temperatures on Regional Climate Extremes Downscaled from the CMIP5 Archive Using the WRF Model. Spero, Tanya L.; Nolte, Christopher G.; Bowden, Jared H.; Mallard, Megan S.; Herwehe, Jerold A. // Journal of Climate;Jan2016, Vol. 29 Issue 2, p839 

    The impact of incongruous lake temperatures is demonstrated using the Weather Research and Forecasting (WRF) Model to downscale global climate fields. Unrealistic lake temperatures prescribed by the default WRF configuration cause obvious biases near the lakes and also affect predicted extremes...

  • How organized is deep convection over Germany? Pscheidt, Ieda; Senf, Fabian; Heinze, Rieke; Deneke, Hartwig; Trömel, Silke; Hohenegger, Cathy // Quarterly Journal of the Royal Meteorological Society;Jul2019 Part B, Vol. 145 Issue 723, p2366 

    Deep moist convection shows a tendency to organize into mesoscale structures. To be able to understand the potential effect of convective organization on the climate, one needs first to characterize organization. In this study, we systematically characterize the organizational state of...

  • Polarimetric Doppler radar analysis of squall line systems crossing Salento Peninsula. Congedo, F.; Prodi, F.; Pasqualucci, F.; Trivellone, G. // Meteorological Applications;Jul2017, Vol. 24 Issue 3, p338 

    ABSTRACT A detailed observational study of squall line thunderstorms, a particular form of mesoscale convective systems arranged in a line that repeatedly affected Salento Peninsula (southern Apulia, Italy) throughout 2015, is presented and discussed. Specifically, three relevant events that...

  • A seasonal and diurnal climatology of precipitation organization in the southeastern United States. Rickenbach, Thomas M.; Nieto‐Ferreira, Rosana; Zarzar, Christopher; Nelson, Brian // Quarterly Journal of the Royal Meteorological Society;Jul2015, Vol. 141 Issue 690, p1938 

    This article describes results from a new four-year (2009-2012) radar-based precipitation climatology for the southeastern United States (SE USA). The climatology shows that a size-based classification between mesoscale precipitation features (MPF) and isolated precipitation reveals distinct...

  • High-Resolution Downscaled Simulations of Warm-Season Extreme Precipitation Events in the Colorado Front Range under Past and Future Climates*. Mahoney, Kelly; Alexander, Michael; Scott, James D.; Barsugli, Joseph // Journal of Climate;Nov2013, Vol. 26 Issue 21, p8671 

    A high-resolution case-based approach for dynamically downscaling climate model data is presented. Extreme precipitation events are selected from regional climate model (RCM) simulations of past and future time periods. Each event is further downscaled using the Weather Research and Forecasting...


Read the Article


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

Try another library?
Sign out of this library

Other Topics