|
Titel |
Numerical simulation of a rare winter hailstorm event over Delhi, India on 17 January 2013 |
VerfasserIn |
A. Chevuturi, A. P. Dimri, U. B. Gunturu |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1561-8633
|
Digitales Dokument |
URL |
Erschienen |
In: Natural Hazards and Earth System Sciences ; 14, no. 12 ; Nr. 14, no. 12 (2014-12-19), S.3331-3344 |
Datensatznummer |
250118806
|
Publikation (Nr.) |
copernicus.org/nhess-14-3331-2014.pdf |
|
|
|
Zusammenfassung |
This study analyzes the cause of the rare occurrence of a winter hailstorm over
New Delhi/NCR (National Capital Region), India. The absence of increased
surface temperature or low level of moisture incursion during winter cannot
generate the deep convection required for sustaining a hailstorm.
Consequently, NCR shows very few cases of hailstorms in the months of
December-January-February, making the winter hail formation a question of
interest. For this study, a recent winter hailstorm event on 17 January 2013
(16:00–18:00 UTC) occurring over NCR is investigated. The storm is simulated
using the Weather Research and Forecasting (WRF) model with the Goddard Cumulus
Ensemble (GCE) microphysics scheme with two different options: hail and graupel.
The aim of the study is to understand and describe the cause of
hailstorm event during over NCR with a comparative analysis of the two options
of GCE microphysics. Upon evaluating the model simulations, it is observed
that the hail option shows a more similar precipitation intensity with the
Tropical Rainfall Measuring Mission (TRMM) observation
than the graupel option does, and it is able to simulate hail precipitation. Using
the model-simulated output with the hail option; detailed investigation on
understanding the dynamics of hailstorm is performed. The analysis based on a
numerical simulation suggests that the deep instability in the atmospheric
column led to the formation of hailstones as the cloud formation reached
up to the glaciated zone promoting ice nucleation. In winters, such
instability conditions rarely form due to low level available potential
energy and moisture incursion along with upper level baroclinic instability
due to the presence of a western disturbance (WD). Such rare positioning is found to be lowering the
tropopause with increased temperature gradient, leading to winter hailstorm
formation. |
|
|
Teil von |
|
|
|
|
|
|