The Linkage between the Warm and the Cold Conveyor Belts in an Idealized Extratropical Cyclone

AbstractThis study continues the investigation of airstreams in idealized moist baroclinic waves and addresses the formation of the cold conveyor belt (CCB), its linkage to the warm conveyor belt (WCB), and their impact on the development of a midlatitude cyclone. The CCB is identified as a coherent bundle of trajectories, characterized by weak ascent and a strong increase of potential vorticity (PV) along the flow, in contrast to the WCB, defined as the trajectories with maximum ascent. The authors illuminate the role of the two conveyor belts in the formation of two strong PV anomalies that form in the upper (WCB, negative PV anomaly) and lower troposphere (CCB, positive PV anomaly), respectively, and thereby establish a link between these airstreams and relevant aspects of the dynamics of extratropical cyclones. The CCB moves close to the surface along the colder side of the bent-back front and experiences a PV increase as it passes below a region of maximum latent heat release at midtropospheric level...

[1]  Andrew L. Hulme,et al.  Synoptic- and Frontal-Scale Influences on Tropical Transition Events in the Atlantic Basin. Part II: Tropical Transition of Hurricane Karen , 2009 .

[2]  R. J. Reed,et al.  A Model-aided Study of the Origin and Evolution of the Anomalously High Potential vorticity in the Inner Region of a Rapidly Deepening Marine Cyclone , 1992 .

[3]  C. Mechoso,et al.  Influence of Surface Drag on the Evolution of Fronts , 1993 .

[4]  D. Raymond,et al.  A Theory for Long-Lived Mesoscale Convective Systems , 1990 .

[5]  B. Hoskins,et al.  On the use and significance of isentropic potential vorticity maps , 2007 .

[6]  D. Lüthi,et al.  The effect of barotropic shear on upper-level induced cyclogenesis : Semigeostrophic and primitive equation numerical simulations , 1998 .

[7]  Ulrich Corsmeier,et al.  The key role of diabatic processes in modifying the upper‐tropospheric wave guide: a North Atlantic case‐study , 2011 .

[8]  K. Browning.  The sting at the end of the tail: Damaging winds associated with extratropical cyclones , 2004 .

[9]  Heini Wernli,et al.  A 15-Year Climatology of Warm Conveyor Belts , 2004 .

[10]  S. Belcher,et al.  Boundary‐layer ventilation by baroclinic life cycles , 2008 .

[11]  Peter H. Haynes,et al.  On the Evolution of Vorticity and Potential Vorticity in the Presence of Diabatic Heating and Frictional or Other Forces , 1987 .

[12]  E. Kessler.  On the distribution and continuity of water substance in atmospheric circulations , 1969 .

[13]  Ying-Hwa Kuo,et al.  Thermal Structure and Airflow in a Model Simulation of an Occluded Marine Cyclone , 1992 .

[14]  Ying-Hwa Kuo,et al.  An adiabatic simulation of the ERICA IOP 4 storm: an example of quasi-ideal frontal cyclone development , 1994 .

[15]  H. Wernli,et al.  Warm Conveyor Belts in Idealized Moist Baroclinic Wave Simulations , 2013 .

[16]  C. M. Penner.  A three‐front model for synoptic analyses , 1955 .

[17]  G. Mellor,et al.  Development of a turbulence closure model for geophysical fluid problems , 1982 .

[18]  T. W. Harrold.  Mechanisms influencing the distribution of precipitation within baroclinic disturbances , 1973 .

[19]  David M. Schultz,et al.  The occlusion process in a midlatitude cyclone over land , 1993 .

[20]  Noboru Nakamura,et al.  Nonlinear Equilibration of Two-Dimensional Eady Waves , 1989 .

[21]  Louis W. Uccellini,et al.  A model-based diagnostic study of the rapid development phase of the Presidents' Day cyclone , 1988 .

[22]  Images in weather forecasting , 1997 .

[23]  J. L. Galloway.  THE THREE-FRONT MODEL: ITS PHILOSOPHY, NATURE, CONSTRUCTION AND USE , 1958 .

[24]  M. Shapiro.  The Role of Turbulent Heat Flux in the Generation of Potential Vorticity in the Vicinity of Upper-Level Jet Stream Systems , 1976 .

[25]  Heini Wernli,et al.  Influence of microphysical processes on the potential vorticity development in a warm conveyor belt: a case‐study with the limited‐area model COSMO , 2012 .

[26]  R. Rotunno,et al.  On the formation of potential-vorticity anomalies in upper-level jet-front systems , 1990 .

[27]  Alan J. Thorpe,et al.  The Evolution and Dynamical Role of Reduced Upper-Tropospheric Potential Vorticity in Intensive Observing Period One of FASTEX , 2000 .

[28]  S. Gray,et al.  Sting Jets in Simulations of a Real Cyclone by Two Mesoscale Models , 2010 .

[29]  S. Belcher,et al.  Moisture transport in midlatitude cyclones , 2010 .

[30]  J. Namias.  The Use of Isentropic Analysis in Short Term Forecasting , 1939 .

[31]  W. L. Godson.  Synoptic properties of frontal surfaces , 1951 .

[32]  K. Browning.  Conceptual Models of Precipitation Systems , 1986 .

[33]  H. Wernli,et al.  Growth and Decay of an Extra-Tropical Cyclone’s PV-Tower , 2000 .

[34]  David M. Schultz,et al.  The Structure and Evolution of a Simulated Midlatitude Cyclone over Land , 1993 .

[35]  The Role of Diffusive Effects On Potential Vorticity In Fronts , 1992 .

[36]  H. Wernli,et al.  A PV Perspective on the Vertical Structure of Mature Midlatitude Cyclones in the Northern Hemisphere , 2012 .

[37]  Heini Wernli,et al.  A Lagrangian‐based analysis of extratropical cyclones. I: The method and some applications , 1997 .

[38]  D. Schultz.  Reexamining the Cold Conveyor Belt , 2001 .

[39]  K. Browning,et al.  Interpretation of Satellite Imagery of A Rapidly Deepening Cyclone , 2007 .

[40]  Numerical simulations of the life cycle of a baroclinic wave , 1995 .

[41]  S. Belcher,et al.  Moisture Transport in Mid-latitude Cyclones , 2010 .

[42]  M. Stoelinga.  A Potential Vorticity-Based Study of the Role of Diabatic Heating and Friction in a Numerically Simulated Baroclinic Cyclone , 1996 .

[43]  I. Takayabu.  Roles of the horizontal advection on the formation of surface fronts and on the occlusion of a cyclone developing in the baroclinic westerly jet , 1986 .

[44]  S. Grønås.  The seclusion intensification of the New Year's day storm 1992 , 1995 .

[45]  Heini Wernli,et al.  Dynamical aspects of the life cycle of the winter storm ‘Lothar’ (24–26 December 1999) , 2002 .

[46]  R. Rotunno,et al.  Effects of Surface Drag on Fronts within Numerically Simulated Baroclinic Waves , 1998 .

[47]  Paul J. Neiman,et al.  The Life Cycle of an Extratropical Marine Cyclone. Part II: Mesoscale Structure and Diagnostics , 1993 .

[48]  Toby N. Carlson,et al.  Airflow Through Midlatitude Cyclones and the Comma Cloud Pattern , 1980 .

[49]  Gary M. Lackmann,et al.  Potential Vorticity (PV) Thinking in Operations: The Utility of Nonconservation , 2008 .

[50]  W. Peltier,et al.  Tropopause Folds and Synoptic-Scale Baroclinic Wave Life Cycles , 1994 .

[51]  C. M. Penner,et al.  Frontal Contour Charts. , 1947 .

[52]  F. Ludlam,et al.  Isentropic relative-flow analysis and the parcel theory , 1966 .

[53]  Peter Clark,et al.  The sting at the end of the tail: Model diagnostics of fine‐scale three‐dimensional structure of the cloud head , 2005 .

[54]  K. Browning,et al.  Structure of a frontal cyclone , 1994 .

[55]  K. Browning,et al.  Attribution of strong winds to a cold conveyor belt and sting jet , 2014 .

[56]  M. Shapiro,et al.  Further Evidence of the Mesoscale and Turbulent Structure of Upper Level Jet Stream–Frontal Zone Systems , 1978 .

[57]  Jonathan E. Martin.  Quasigeostrophic Forcing of Ascent in the Occluded Sector of Cyclones and the Trowal Airstream , 1999 .

[58]  A. Stohl.  A 1-year Lagrangian ``climatology'' of airstreams in the Northern Hemisphere troposphere and lowermost stratosphere , 2001 .

[59]  M. Tiedtke.  A Comprehensive Mass Flux Scheme for Cumulus Parameterization in Large-Scale Models , 1989 .

[60]  Heini Wernli,et al.  A Lagrangian‐based analysis of extratropical cyclones. II: A detailed case‐study , 1997 .

[61]  K. Emanuel,et al.  Potential Vorticity Diagnostics of Cyclogenesis , 1991 .

[62]  S. Belcher,et al.  On the dependence of boundary layer ventilation on frontal type , 2009 .

[63]  U. Schubert,et al.  LLM – a nonhydrostatic model applied to high-resolving simulations of turbulent fluxes over heterogeneous terrain , 2002 .

[64]  Heini Wernli,et al.  Structure and evolution of an isolated semi‐geostrophic cyclone , 1993 .