Transcript 071109Tainan_TIMREX_PLANNING_Medina.ppt

Scientific Objectives and Required Facilities
• Scientific Objectives
– Investigate the vertical structure of precipitation over
Taiwan’s terrain
– Investigate the structure of the terrain-modified airflow
• Required Facilities: S-Pol and upper-air soundings
• Highly desired: Vertically-pointing precipitation radar
Socorro Medina, Robert Houze, and Stacy Brodzik
TIMREX Planning Meeting, Tainan, Taiwan, 9 November 2007
Results from previous field
experiments (MAP and
IMPROVE-2) to illustrate how SPol sectors of RHI scans were
used to accomplish similar
objectives
Cross-barrier distribution of time-averaged
reflectivity as a function of height
3-hour mean S-Pol reflectivity (1400-1700 UTC 28 Nov 2001 )
Oregon Cascades
Distance from the radar (km)
Pacific Coastal R. Valley
Cascades
Medina et al. (2007)
29 Nov
28 Nov
Terrain elevation (km)
Time (UTC) 
Cross-barrier distribution of S-Pol reflectivity aloft as a function of
time - Maximum reflectivity (between 3-10 km)
09
06
03
00
21
18
15
12
09
06
03
00
dBZ
30
20
10
0
-10
-20
-30
1.8
1.4
1.0
0.6
0.2
-150
Oregon Cascades
-100
50
0
50
100
Distance from radar (km)
Pacific Coastal R. Valley
Cascades
150
Medina et al. (2007)
PBL flow adjacent to the terrain and
embedded convection (S-Pol data)
Radial velocity (m/s)
Low-level flow
rising over terrain
Alps
Reflectivity (dBZ)
Maximum echo
on top 1st peak of
terrain
Particle Type
(frequency of
occurrence)
Stratiform
background
punctuated
by graupel
07-10 UTC 20 Sep 1999 mean
Graupel
Dry snow
Wet snow
S-Pol
NNW
Distance from the radar (km)
Rotunno and Houze (2007)
Evaluation of terrain-modified PBL flows
simulated by numerical mesoscale models
Time-averaged observed radial
velocity (m/s) (S-Pol)
Alps
Alps
S-Pol
NW
Distance from radar (km)
08-11 UTC 21 Oct 1999 mean
Time-averaged simulated radial
velocity (m/s) (MESO-NH)
Alps
Alps
S-Pol
NW
Distance from radar (km)
Vertically pointing radar data
Reflectivity (dBZ)
Radial velocity (m/s)
Time
Houze and Medina (2005)
Other requirements
• Desk space for two people in the
Operation Center (OPS) or for one person
at the OPS and one person at the S-Pol
site (depending on how much data can be
transmitted from S-Pol to OPS)
• Internet access