Simulation Experiment of Squall Line Observed in the Huaihe RiverBasin, China
Kazuhisa Tusboki (1), Atsushi Sakakibara (2)
(1) Hydrospheric Atmospheric Research Center, Nagoya University
(2) Research Organization for Information Science and Technology
An intensive field observation (IFO) of GAME/HUBEX (the GEWEX Asian Monsoon Experiment/ the Huaihe River Basin Experiment) was performed in the Huaihe River Basin, China during the period from 11 June 1998 to 22 July 1998. During IFO, a squall line was observed by three Doppler radars. The squall line approached the radars from the southwest around 10 UTC, 16 July 1998. It passed over the radars around 1130 UTC and moved northeastward with decaying. The squall line extended from the northwest to the southeast with a width of a few tens kilometers. Radar echo showed that the squall line consisted of intense convective
cells. Some of cells reached to a height of 17 km. After the squall line passed over the radar sites, a stratiform precipitation was extending behind the convective leading edge.
In order to simulate an evolution of a convective cloud storm, we are now developing a cloud resolving model which is named as the Cloud Resolving Storm Simulator (CReSS). We performed a simulation experiment of the observed squall line using CReSS with very high resolution in a large three-dimensional domain. The inhomogeneous initial field was given by the dual Doppler radar observation and the sounding.
In this simulation experiment, the both horizontal and vertical grid sizes were 300 m within a domain of 170 km times 120 km. Cloud microphysics was the cold rain type. An initial condition was provided by a dual Doppler analysis and sounding data. The boundary condition was the wave-radiating type.
The result of the simulation experiment shows that CReSS successfully simulated the development and movement of the squall line. The convective reading edge was maintained by the replacement of new convective cells and the simulated squall line moved to the northeast which is similar to the behavior of the observed squall line. Convective cells reached to a height of about 14 km with large production of graupel above the melting layer. The rear inflow was significant as the observation. A stratiform region extended with time behind the leading edge. Cloud extended to the southwest to form a cloud cluster.
Submittal Information
Name :
Date :
Kazuhisa Tsuboki
31-May-01-10:55:04
Organization :
Theme :
Hydrospheric Atmospheric Research Center, Nagoya University
