Analysis of Raindrop Shapes, Fall Velocities, and Scattering Calculations during Tropical Storm Nate

Merhala Thurai, Sophie Steger, Franz Teschl, Michael Schönhuber

Publikation: Beitrag in einer FachzeitschriftArtikelForschung

Abstract

Tropical storm Nate, which was a powerful hurricane prior to landfall along the Alabama coast, traversed north towards our instrumented site in Hunstville, AL. The rain bands lasted 18 h and the 2D-video disdrometer (2DVD) captured the event which was shallow and indicative of pure warm rain processes. Measurements of raindrop size, shape and velocity distributions are quite rare in pure warm rain and are expected to differ from cold rain processes. In particular, asymmetric shapes due to drop oscillations and their impact on polarimetric radar signatures in warm rain have not been studied so far. Recently, the 2DVD data has been used for 3D reconstruction of asymmetric raindrop shapes but their fraction (relative to the more common oblate shapes) in warm rain has yet to be ascertained. Here we compute the scattering matrix drop-by-drop using Computer Simulation Technology integral equation solver for drop sizes>2.5 mm. From the scattering matrix elements, the polarimetric radar observables are simulated by integrating over 1 minute consecutive segments of the event. These simulated values are compared with dual-polarized C-band radar data located at 15 km range from the 2DVD site to evaluate the contribution of the asymmetric drop shapes.
Originalspracheenglisch
Aufsatznummer2019100284
Seitenumfang16
FachzeitschriftAtmosphere
DOIs
PublikationsstatusElektronische Veröffentlichung vor Drucklegung. - 2019

Fingerprint

raindrop
scattering
radar
matrix
computer simulation
hurricane
calculation
rain
analysis
oscillation
coast
video

Fields of Expertise

  • Information, Communication & Computing

Dies zitieren

Analysis of Raindrop Shapes, Fall Velocities, and Scattering Calculations during Tropical Storm Nate. / Thurai, Merhala; Steger, Sophie; Teschl, Franz; Schönhuber, Michael.

in: Atmosphere, 2019.

Publikation: Beitrag in einer FachzeitschriftArtikelForschung

@article{1bbf61a6e3754fceac377c42beb0620f,
title = "Analysis of Raindrop Shapes, Fall Velocities, and Scattering Calculations during Tropical Storm Nate",
abstract = "Tropical storm Nate, which was a powerful hurricane prior to landfall along the Alabama coast, traversed north towards our instrumented site in Hunstville, AL. The rain bands lasted 18 h and the 2D-video disdrometer (2DVD) captured the event which was shallow and indicative of pure warm rain processes. Measurements of raindrop size, shape and velocity distributions are quite rare in pure warm rain and are expected to differ from cold rain processes. In particular, asymmetric shapes due to drop oscillations and their impact on polarimetric radar signatures in warm rain have not been studied so far. Recently, the 2DVD data has been used for 3D reconstruction of asymmetric raindrop shapes but their fraction (relative to the more common oblate shapes) in warm rain has yet to be ascertained. Here we compute the scattering matrix drop-by-drop using Computer Simulation Technology integral equation solver for drop sizes>2.5 mm. From the scattering matrix elements, the polarimetric radar observables are simulated by integrating over 1 minute consecutive segments of the event. These simulated values are compared with dual-polarized C-band radar data located at 15 km range from the 2DVD site to evaluate the contribution of the asymmetric drop shapes.",
author = "Merhala Thurai and Sophie Steger and Franz Teschl and Michael Sch{\"o}nhuber",
year = "2019",
doi = "10.20944/preprints201910.0284.v1",
language = "English",
journal = "Atmosphere",
issn = "2073-4433",
publisher = "MDPI AG",

}

TY - JOUR

T1 - Analysis of Raindrop Shapes, Fall Velocities, and Scattering Calculations during Tropical Storm Nate

AU - Thurai, Merhala

AU - Steger, Sophie

AU - Teschl, Franz

AU - Schönhuber, Michael

PY - 2019

Y1 - 2019

N2 - Tropical storm Nate, which was a powerful hurricane prior to landfall along the Alabama coast, traversed north towards our instrumented site in Hunstville, AL. The rain bands lasted 18 h and the 2D-video disdrometer (2DVD) captured the event which was shallow and indicative of pure warm rain processes. Measurements of raindrop size, shape and velocity distributions are quite rare in pure warm rain and are expected to differ from cold rain processes. In particular, asymmetric shapes due to drop oscillations and their impact on polarimetric radar signatures in warm rain have not been studied so far. Recently, the 2DVD data has been used for 3D reconstruction of asymmetric raindrop shapes but their fraction (relative to the more common oblate shapes) in warm rain has yet to be ascertained. Here we compute the scattering matrix drop-by-drop using Computer Simulation Technology integral equation solver for drop sizes>2.5 mm. From the scattering matrix elements, the polarimetric radar observables are simulated by integrating over 1 minute consecutive segments of the event. These simulated values are compared with dual-polarized C-band radar data located at 15 km range from the 2DVD site to evaluate the contribution of the asymmetric drop shapes.

AB - Tropical storm Nate, which was a powerful hurricane prior to landfall along the Alabama coast, traversed north towards our instrumented site in Hunstville, AL. The rain bands lasted 18 h and the 2D-video disdrometer (2DVD) captured the event which was shallow and indicative of pure warm rain processes. Measurements of raindrop size, shape and velocity distributions are quite rare in pure warm rain and are expected to differ from cold rain processes. In particular, asymmetric shapes due to drop oscillations and their impact on polarimetric radar signatures in warm rain have not been studied so far. Recently, the 2DVD data has been used for 3D reconstruction of asymmetric raindrop shapes but their fraction (relative to the more common oblate shapes) in warm rain has yet to be ascertained. Here we compute the scattering matrix drop-by-drop using Computer Simulation Technology integral equation solver for drop sizes>2.5 mm. From the scattering matrix elements, the polarimetric radar observables are simulated by integrating over 1 minute consecutive segments of the event. These simulated values are compared with dual-polarized C-band radar data located at 15 km range from the 2DVD site to evaluate the contribution of the asymmetric drop shapes.

U2 - 10.20944/preprints201910.0284.v1

DO - 10.20944/preprints201910.0284.v1

M3 - Article

JO - Atmosphere

JF - Atmosphere

SN - 2073-4433

M1 - 2019100284

ER -