Studies on structure and formation/development
Mechanisms of Mesoscale Convective Systems
- An address of our new project -
Masanori Yoshizaki
Meteorological Research Institute, Japan Meteorological Agency, Japan
A new project of ``Studies on structure and formation/development
mechanisms of mesoscale convective systems'' supported by Japan Science and
Technology Corporation (JST) - Core Research for Evolutional Science and
Technology (CREST) started from October 1998. It continues until October
2003. We expect that this project stimulates research activity of mesoscale
meteorology in Japan and makes breakthrough for new and further studies.
We opened a homepage (HP) of this project in order to communicate and
give/take information. It will be frequently renewed when interesting news
and reports are attained. We hope many people utilize this HP and get
fruitful products through active communication and cooperation.
I am a principal researcher of this project. Mesoscale convective systems
(MCSs) are my main concern. MCSs sometimes bring severe weathers such as
gust wind, heavy precipitation, lightening and so on, and therefore the logo
mark in the title was made as a combination of three legendary gods;
lightening (left), rain (dragon, middle) and wind (right). Ancient Japanese
people believed that such meteorological phenomena were brought by these
gods. Now we want to see them more clearly and elucidate their works by this
project. Hereafter I present outlines of objectives, research activity and
observation plans under the project.
Objectives of this project:
MCSs have horizontal scales of 100km, consisting of convective and
stratiform regions. Their horizontal form is various; line-shaped,
hook-shaped, and so on. They last for a long time by self-enhancement and
organization. MCSs play a key role on cycles of water and energy in the
global circulation and also bring heavy precipitation, sometimes producing
serious disasters. In Japan, MCSs occur with Baiu front, convergence bands/
small-scale cyclones over Japan Sea in winter, typhoons, and thunderstorms
over central mountains in summer. They are an important part of multi-scale
structures.
In this project, clarification of MCSs and multi-scale structures is aimed
at. For these purposes, studies combined with field experiments, analyses,
and numerical simulations are systematically performed about Baiu front
around Kyushu and convergence bands/ small-scale cyclones over Japan Sea in
winter. As field experiments, surface networks of Doppler radar, upper
sounding, GPS, boundary-layer radar (BLR) and observation vessels, and
mobile airplanes are combined. We want to elucidate inner structures of
MCSs, their formation/development mechanisms, accompanying disturbances such
as intermediate-scale disturbances and relationships between MCSs and
environmental fields.
Processes of research:
In this project, our research is processed as follows; (1) purchase of
meso-scale observation instruments and construction of ground-based
observation system, (2) special observations of MCSs, (3) production of data
base of special observation, (4) analytical studies, (5) numerical studies,
and (6) comparative studies with other MCSs and summary.
In particular, in (1) we purchased two BLRs, two surface meteorological
systems and one microwave radiometer for measuring vertical profiles of
temperature and moisture. We want to make a prototype of ground-based
measuring system by combining these instruments. In (2), total observations
by combining surface networks of Doppler radar, upper sounding, GPS and
BLRs, and mobile airplanes are planed once every fiscal year. Further, in
(5), real-time (but not operational) numerical simulations will be performed
during special observation periods by using a non-hydrostatic numerical
model (MRI-NHM). By utilizing these numerical results, mechanisms of
self-enhancement and organizations of MCSs are studies.
Research plan of fiscal year: (Fiscal year starts in April in Japan.):
- October 1998- March 1999:
Two BLRs, two surface meteorological systems and one microwave radiometer
for measuring vertical profiles of temperature and moisture were purchased.
- April 1999 - March 2000:
Observation of Baiu front over Kyushu and East China Sea. (X-BAIU-99)
- April 2000 - March 2001:
Observation of convergence bands/ small-scale cyclones over Japan Sea in
winter (January 2001)
- April 2001 - March 2002:
Observation of convergence bands/ small-scale cyclones over Japan Sea in
winter (January 2002).
- April 2002 - March 2003:
Observation of Baiu front over Kyushu and East China Sea (June - July 2002).
- April 2003 - October 2003:
International symposium of meso-scale precipitation systems.
Note: The observation plans may be changed when cooperation with other
observations is required.
Corresponding author address:
Masanori Yoshizaki
1-1 Nagamine,Tsukuba,Ibaraki 305-0052 JAPAN
Tel: +81-298-53-8631
Fax: +81-298-53-8649
E-mail: myoshiza@mri-jma.go.jp