One event of a tropical storm typically observed in northern Australia, known as Hector, is investigated using high resolution model output from the Fifth-Generation Mesoscale Model (MM5), observations from a ground-base weather radar located in Berrimah (Australia), and data from the Tropical Rainfall Measuring Mission (TRMM) satellite. The analysis is carried out by tracking the full life-cycle of Hector, from pre-storm stage to the decaying stage. In both the pre-storm stage, characterized by non precipitating cells, and the triggering stage, when the Hector storm is effectively initiated, an analysis is performed with the aid of high spatial and temporal resolution MM5 output and the Berrimah ground-based radar imagery. During the mature (‘old’) stage of Hector, considering the conceptual model for tropical convection suggested by Houze (1997), TRMM Microwave Imager satellite-based data were added to ground-based radar data to analyze the storm vertical structure (dynamics, thermodynamics and hydrometeors contents). Model evaluation with respect to observations (radar reflectivity and TRMM data) suggests that MM5 performed fairly well in reproducing the dynamics of Hector, providing support to the assertion that the strength of convection, in terms of vertical velocity, is largely contributing to the vertical distribution of hydrometeors. Moreover, the stages of the storm and its vertical structure display good agreement with Houze’s aforementioned conceptual model. Finally, it was found that the most important triggering mechanisms for this Hector event are topography, sea-breeze, and gust front produced by previous convection.

Investigating Hector convective development and microphysical structure by high resolution model simulations, ground-based radar data and TRMM satellite data

FERRETTI, Rossella;
2014

Abstract

One event of a tropical storm typically observed in northern Australia, known as Hector, is investigated using high resolution model output from the Fifth-Generation Mesoscale Model (MM5), observations from a ground-base weather radar located in Berrimah (Australia), and data from the Tropical Rainfall Measuring Mission (TRMM) satellite. The analysis is carried out by tracking the full life-cycle of Hector, from pre-storm stage to the decaying stage. In both the pre-storm stage, characterized by non precipitating cells, and the triggering stage, when the Hector storm is effectively initiated, an analysis is performed with the aid of high spatial and temporal resolution MM5 output and the Berrimah ground-based radar imagery. During the mature (‘old’) stage of Hector, considering the conceptual model for tropical convection suggested by Houze (1997), TRMM Microwave Imager satellite-based data were added to ground-based radar data to analyze the storm vertical structure (dynamics, thermodynamics and hydrometeors contents). Model evaluation with respect to observations (radar reflectivity and TRMM data) suggests that MM5 performed fairly well in reproducing the dynamics of Hector, providing support to the assertion that the strength of convection, in terms of vertical velocity, is largely contributing to the vertical distribution of hydrometeors. Moreover, the stages of the storm and its vertical structure display good agreement with Houze’s aforementioned conceptual model. Finally, it was found that the most important triggering mechanisms for this Hector event are topography, sea-breeze, and gust front produced by previous convection.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11697/9836
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 3
  • ???jsp.display-item.citation.isi??? 2
social impact