Summary of the observation

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Summary of the observation
Summary of the observationrelated advances in MAP
C. Flamant
IPSL/SA, CNRS, Paris, France
With contributions from:
K. Baumann-Stanzer, J.-L. Caccia, B. Chiamani, A. Dabas, P. Drobinski, D. Durand,
S. Emeis, M. Furger, U. German, A. Gohm, V. Grubisic, M. Hagen, K.-P. Hoinka,
R. Houze, M. Lothon, G. Mayr, B. Neininger, R. Ranzi, H. Richner, M. Rotach,
F. Roux, C. Schär, G. Scialom, M. Sorocco, S. Soula, R. Smith, R. Steinacker,
M. Steiner, S. Tschannett, S. Vogt, H. Volker, M. Wüest
In memoriam: T. Vrhovec
ICAM/MAP 2005, Zadar, 27 May 2005
Reasons why was MAP designed
1. New scientific questions, sometimes induced by high resolution
numerical simulation
2. Need for high resolution (temporal and spatial) measurements
Î remote sensing instruments !
(+ multi-lidar, multi-radar operations)
Î very dense surface networks
Î multi-aircraft operations (up to 6 aircraft during some GW
missions)
Î « Curtains » of data (lidars, radars, dropsondes)
Î Meteosat rapid scan
An « instrumental success »
• 17 IOPs totalling 35 days of observations
• 110 hours of research multi-aircraft
missions
• 6800 radios-sondes launched
• 84 constant level balloons launched
• 864 hours of research radar data
• 187 hours of airborne lidar data
• 1700 hours of scintillometer data
• …… and so much more…
All data are freely accessible on the Internet
from the MDC http://www.map.ethz.ch
Radars
• S-POL, RONSARD, Monte-Lema
• Doppler On Wheel
• Airborne ELDORA/ASTRAIA and NOAA Doppler radar
MAP sub-project: P1
Objectives:
• Dynamics and microphysics within convective
and stratiform precipitating systems
• Clear air dynamics in the vicinity of precipitating systems
• Small scale patterns of precipitation
Swiss operational Radar
Monte Lema
C band, volumic, Doppler
US Radar S-POL (NCAR)
S band , volumic sectorial,
Doppler, polarimetric
French Radar Ronsard
(CETP)
C band, volumic, Doppler
Lago Maggiore Target Area
Wind profilers
UHF / VHF
RS station
Milan-Linate
SPOL
RONSARD
MONTE LEMA
Monte Lema / Ronsard / SPOL
→ Kinématic and microphysic fields (every 15 minutes)
+ Wind profiler VHF
→ Structure of flow in altitude (every 15 minutes)
+ Milan-Linate radiosoudings
→ Thermodynamic Profile and stability study (every 6 hours)
Tabary, Scialom et al.
Importance of microphysics : numerical
experiments show that a reaslistic
representation of cloud microphysics in the
simulations is key to reproducing the
dynamics of such events.
Radar precipitation measurement in the Alps - a challenge
6
km
4
We need ...
2
0
Lema
- a scan geometry with
high resolution in space
-a sophisticated elimination of ground clutter
from main and side lobes
- a robust correction for
growth and phase change
between height of
measurement and ground
(profile correction)
Big improvements triggered by MAP
Objective verification based on data of 1997-2004 at 58 gauge
locations:
vicinity
whole Switzerland
Bias
Bias
Scatter
POD
FAR
ETS
Summer 1997
0.63
0.50
2.7
0.84
0.34
0.40
Summer 2004
1.01
1.003
1.7
0.90
0.15
0.63
Factor
Factor
Factor
From Urs German (next talk) we will hear more about :
- 1999, the time of the SOP?
- how did they manage to reduce BIAS, Scatter and FAR?
Evidence of systematic drainage flows during rainy events
Steiner et al.
(QJ 2003)
Bousquet & Smull
(QJ 2003;
JAM 2003)
Lidars
• Airborne CNRS and DLR H2O DIALs
• Airborne CNRS/DLR Doppler WIND
• Airborne backscatter lidar SABL
• NOAA/ETL and CNRS Doppler lidars
MAP sub-projects: P1, P2, P4, P5, P6, P7, P8
Objectives:
• Moisture inflow documentation
• PV streamers structure
• Fohn flow structure and characteristics in Alpine valleys
• Characteristics of GW waves in the lee of Alpine peaks
• PBL structure in complex terrain
Structure of a PV streamer: water vapor mixing ratio
Comparison
between
ECMWF,
MesoNH, and
observations
from the DLR
WV DIAL
Hoinka et al. (QJ 2003)
Structure of the gap flow during föhn events:
evidence of hydraulic behavior
Flamant et al.
(QJ 2002)
Gohm and Mayr
(QJ 2004)
Airborne DIAL LEANDRE 2
Supercritical
flow
Hydraulic
jump
Innsbruck
Subcritical
flow
NOAA
Doppler
Lidar
E
Flamant et al.
(QJ 2002)
Durran et al.
(QJ 2003)
Airborne lidar
Deflection
Ground-based lidar
Deflection
E
Mesoscale structure of the flow along the Wipp Valley
Strong winds on
the northern
slopes of the
Alps.
No wind in the Wipp
valley (Innsbrück)
Above the Alps, in the
unperturbed region, the flow is
from West-North-West as
predicted by ARPEGE
The flow
channelled
within the
Adigio valley
rises above the
Brenner.
The air in the Adigio
valley is channelled and
flows to the north.
Weaker winds
on the south
slopes of the
Alps.
Strong channelled
winds in the Adige
valley.
Reitebuch et al.
(QJ 2003)
South flow
The air coming from the
south is blocked by the
Alps and turns east.
Cold-pool/föhn interactions in the Alpine Rhine Valley
µ-barograph
Vaduz
Merlin IV
Scorer (III)
Flamant
et al.
(submit.
QJ)
K-H instability?
Flow splitting in the Rhine Valley during south föhn events
Drobinski et al. (QJ 2003; BLM 2001, 2003)
Shallow föhn
Deep föhn
Westerly flow
(shallow föhn)
700 m
1000 m
1500 m
2000 m
Vertical extension of flow splitting > 300 m
Southerly
flow (deep
föhn)
700 m
1000 m
1500 m
2000 m
Vertical extension of flow splitting < 300 m
• Shallow föhn: coexistence of cold katabatic flow in
transverse E-O oriented valleys and the channeled föhn
flowing over the cold air
• Deep föhn: decrease of the vertical extension of the « flow
splitting » at the intersection of the Seez and Rhine valleys
with respect to shallow föhn cases (specific to the Rhine
valley)
The geometry of the
network of valleys is
an important actor of
the onset and spatial
structure of föhn
Other remote sensing instruments
• SODARs
• Wind profilers
• Scintillometers
MAP sub-projects: P4, P5
Objectives:
• describe the life cycle of föhn (onset->breakup)
in Alpine valleys
• enhance knowledge on cold-pool/föhn interactions
Life cycle of a¨föehn event
40
Querwindgeschwindigkeit, m/s
22 - 23 Oktober 1999
30
20
10
0
vhor (Flusa)
-10
vhor (Ergellen)
Horizontal velocity
-20
0
6
12
18
Zeit, h MEZ
24
6
12
3
22 - 23 Oktober 1999
Furger et al. (JAOT 2001)
MAP-FORM Scintillometer Setup
225
Swiss Y (km)
223
Flusa
222
F
221
er
e Riv
Rhin
224
1
0
-1
-2
-3
-4
-5
vver (Flusa)
-6
vver (Ergellen)
Vertical velocity
-7
0
Triesenberg
F
Sevelen
220
219
218
Vertikalkomponente, m/s
2
F
Ergellen
217
752 753 754 755 756 757 758 759 760 761
Swiss X (km)
6
12
18
Zeit, h MEZ
24
6
12
• Maximum horizontal wind speeds were close to 35 m s-1
• Vertical wind component showed persistent up- or
downward motion of several meters per second
• Onset of foehn was generally a slow process, while
breakdown of foehn occurred rather quickly
Light Research Aircraft
• Eco-Dimona HB 2335
MAP sub-project: P5, P8
Objectives:
• detail 3D flow structure in Alpine valleys
• map turbulence in Alpine valleys
• Validation Model results
Mapping turbulence in an Alpine valley
Weigel and Rotach (QJ 2004)
Measuring turbulent fluxes at the top of the cold pool
Stefan Gubser
Hans Richner
IACETH Zurich
Metair "Dimona"
foehn
Qt
?
?
?
?
z
Qb - Qt = cp·ρ·z·(dθ/dt)
cold pool
S
Rhine valley
surface station
Lustenau
(ZAMG, Wien)
N
assumptions:
mean density
mean depth of cold pool
measured:
Qb
1.0 kg/m3
100. m
daily mean of surface heatflux
15 W/m2
typical heat flux on top of cold pool -15 W/m2
total heat input
30 W/m2
computed:
mean heating rate
ongoing: computation of momentum
flux for estimating entrainment
3·10-4 K/s
= 26. K/d
GPS
• MAGIC network
• additional station installed in Milano
MAP sub-project: P1
Objectives:
• ECMWF operational analyses and MAP reanalyses
validation
• Estimate moisture inflow into convective systems
Validation of ECMWF operational analyses
and MAP reanalyses during the SOP period
Bock et al.
(QJ 2005)
•
•
•
ECMWF analyses: OPER (1999), CTRL
and MAPRA (2002) 3-hourly fields
1-hourly obs.
GPS: 21 stations
Radiosonde: 14 sites 6-hourly obs.
•Dry bias in all 3 ECMWF analyses compared to GPS
•Dry bias in RS data is properly screened during
assimilation at most sites (except in Cagliari, Vipiteno, Nice)
•Analysis of time series (not shown) reveals differences
in model - GPS PWC of up to 5-10 kg m-2 associated with
severe weather events
BIAS
Data synergy
• VERA
• MANDOPAS
MAP sub-project: P5
Objectives:
• Provide detailed analyses of the flow in the Rhine Valley
• Enhance knowledge on the life cycle of föhn
Evaluate ultra-small-scale models using VERA
potential temperature
24. 10. 1999 08:00UTC
-
Difference: model - analysis
+
+
+
+
-
Isoline distance: 1K
Chimani et al. (MZ 2005)
[K]
Heat and moisture budgets from observationsusing
MANDOP 4D VAR analysis
Heat: profilers, RDS
and aircraft
Flamant et al. (submit. QJ)
Moisture: profilers, RDS
and airborne DIAL
Satellite data
• Meteosat Rapid Scan
MAP sub-project: P1, P6
Objectives:
• analyse GW characteristics (geometry, propagation)
• track convective cells during their development
• identify and track features in stratiform clouds
Meteosat-6 for MAP
¾ Geostationary Satellite
¾ Rapid Scans: images every 5 Minutes
¾ Location: 9° West
¾ Data from three chanels: VIS, IR and WV
¾ Rectified and non calibrated data
Convective cell development
20. 09. 1999, 09:00 – 16:00 UTC, IR images
5 minute data
30 minute data
Bollinger, Binder and Rossa (MZ 2003)
Tracking features in stratiform precipitative systems
30-Minute Interval
5-Minute Interval
Bollinger, Binder and Rossa (MZ 2003)
Why was MAP an « instrumental success » ?
1. New scientific questions, sometimes induced by high resolution
numerical simulation
2. Need for high resolution (temporal and spatial) measurements
Î remote sensing instruments !
(+ multi-lidar, multi-radar operations)
Î very dense surface networks
Î multi-aircraft operations (up to 6 aircraft during some GW
missions)
Î « Curtains » of data (lidars, radars, dropsondes)
Î Meteosat rapid scan
The Convective and Orographically-induced
Precipitation Study (COPS)
Effort lead by Volker Wulfmeyer (IPM) University of Hohenheim, Stuttgart, Germany
A field experiment within the Priority Program 1167 PQP
Goal: Advance the quality of forecasts of orographically-induced
convective precipitation by 4D observations and modeling of its life cycle
Region:
Southwestern Germany,
eastern France
Duration:
3 months
Date:
Summer 2007
Features:
Severe thunderstorm
activity but low QPF skill
Information: www.uni-hohenheim.de/sppiop/
COPS „Natural convection
laboratory“
Suggested area (270 x 150
km2)
Supersite