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Thunderstorm Tracking and Nowcasting using 3D Lightning and Radar Data in Southern Germany. Vera Meyer [1] - [email protected], H. Höller [2], H.-D. Betz [3] , K. Schmidt [2]. [1] Central Institute for Meteorology and Geodynamics, Hohe Warte, Vienna - PowerPoint PPT Presentation
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1
[1] Central Institute for Meteorology and Geodynamics, Hohe Warte, Vienna
[2] Deutsches Zentrum für Luft und Raumfahrt, Institut für Physik der Atmosphäre,
Oberpfaffenhofen, Deutschland
[3] Physics Department, University of Munich, Germany
Vera Meyer [1] - [email protected],H. Höller [2], H.-D. Betz [3] , K. Schmidt [2]
Convection Week 2011, Session 3
Thunderstorm Tracking and Nowcastingusing 3D Lightning and Radar Data in Southern Germany
2
PROJECT RegioExAKT www.regioexakt.de
Regional Risk of Convective Extreme Weather Events:User-oriented concepts for optimised thunderstorm nowcasting,with focus on the needs of Munich Airport
Coordinator: Dr. Nikolai Dotzek
MUNICH AIRPORTHEAVY RAIN15 Juni 2007 40,5 l/m² zw. 18.00 –21.00 h
HAIL DAMAGE
Boeing 737, Geneva 15 August 2003
intense rainhaillightning strikeswind gustsetc.
MOTIVATION
3
LINET - Lightning Detection Network
- ‘total lightning’ detection
- 2008 app. 100 sensors in Central Europe
- magnetic field measurements
- TOA (time of arrival) method
- event-height parametercomprehensive discrimination of ‘cloud’ and ‘cloud-to-ground’ lightning
MOTIVATION
4
Abbreviations
IC (cloud lightning)in-cloud, inter-cloud, intra-cloud,cloud-to-air
CG (cloud-to-ground)cloud – to – ground
TL (total lightning)sum (IC + CG)
0 °C
-15 °C
CG CG
IC IC
IC
LIGHTNING TYPES
MOTIVATION
5
high-precision lightning detection.
‚NORMAL STORM‘
cloud lightning
cloud-to- ground lightning
MOTIVATION
LINET 3D-Visualisierung
‚SEVERE STORM‘
6
THUNDERSTORM TRACKING and NOWCASTING
temporal evolution of LIGHTNING cell parameters
cell track
MUNICH AIRPORT
lightning-cell
14:45 15:00 15:15 15:30
total lightningcloud lightningcloud-to-groundlightning
time
MOTIVATION
7
cell track
MUNICH AIRPORT
lightning-cell
cell nowcasts
THUNDERSTORM TRACKING and NOWCASTING
14:45 15:00 15:15 15:30
total lightningcloud lightningcloud-to-groundlightning
time
now prognosis
temporal evolution of LIGHTNING cell parameters
MOTIVATION
8
GOAL:
to assess the usability of 3D total-lightning data forthunderstorm nowcasting
separately and in combination with other data sources (radar)
INTRODUCTION
INTRODUCTION
9
GOAL:
to assess the usability of 3D total-lightning data forthunderstorm nowcasting
separately and in combination with other data sources (radar)
INTRODUCTION
INTRODUCTION
identificationtracking
prediction
10
GOAL:
to assess the usability of 3D total-lightning data forthunderstorm nowcasting
separately and in combination with other data sources (radar)
INTRODUCTION
INTRODUCTION
identificationtracking
prediction
cell evolution
11
GOAL:
to assess the usability of 3D total-lightning data forthunderstorm nowcasting
separately and in combination with other data sources (radar)
- develop a nowcasting method based on lightning information
- develop a method to compare lightning-cell information with information from other data sources (radar)
verify lightning-cell properties in case-studies
evaluate the statistical information content of 3D lightning information
INTRODUCTION
INTRODUCTION
12 INTRODUCTION
May – September 2008
RESEARCH DOMAIN and OBSERVATION PERIOD
13 METHOD
ec-TRAM – tracking and monitoring of electrically charged convective cells
combines cell informations from independently tracked lightning- and radar-cells
NOWCASTING APPROACH ec-TRAM
14 3
DWD Radar Site Fürholzen (Munich)2D reflecitvity maps, low level scandomain [200 km x 200 km]resolution [1 km x 1 km], [5 min]
LINET lightning data, nowcast GmbH3D TOA method in VLF/LF regime, IC/CG discrimination
2D discharge event maps
cell clustering: time interval 3 min
minimum distance 6 km
ec-TRAM – tracking and monitoring of electrically charged convective cells
NOWCASTING APPROACH ec-TRAM
3METHOD
15
NOWCASTING APPROACH ec-TRAM
combines the cell informations of lightning cells and radar cells
cell assignment via spatial overlap
cell identification parameter (optimized)
lightning cell: threshold of 1 event
lightning data: amplitude |A| > 2.5 kA
radar cell: threshold of 33 dBZ
radar-cells
lightning-cell
4METHOD
Rad-TRAM
[Kober,2009]
li-TRAM
[Meyer,2010]
16
NOWCASTING APPROACH ec-TRAM
cell assignment via spatial overlap
cell identification parameter
lightning cell: threshold of 1 event
radar cell: threshold of 33 dBZ
radar-cells
lightning-cell ec-cells
combines the cell informations of lightning cells and radar cells
4METHOD
ec-TRAM
[Meyer,2010]
Rad-TRAM
[Kober,2009]
li-TRAM
[Meyer,2010]
17
example: ec-TRAM nowcasting map (detail) with cell contours, tracks and prognoses of an electrically charged ‚ec-cell‘.
radar cell: Reflectivity map (blue shaded) cell track (white line), actual cell contour (white polygons), cell prognoses for 10 minutes (dark grey polygons), and 20 minutes (light grey polygons)
lightning cell: discharge events clustered for 3 minutes (green crosses) actual cell (red polygon)
cell track
ec-cells
NOWCASTING APPROACH ec-TRAM
5METHOD
18
18
radar sites
x Fürholzen
x POLDIRAD
MUC Munich Airport
M Munich
R Regensburg
A Augsburg
P
F
25 June 2008
TEMPORAL EVOLUTION of ec-TRAM CELL PARAMETER
South Germany
Austria
CASE STUDY
19
19
20
15:3
0
15:4
5
16:0
0
16:1
5
16:3
0
16:4
5
17:0
0
17:1
5
17:3
0
17:4
5
18:0
0
18:1
5
18:3
00
100
200
300
400
500
[km
2]
LIFE CYCLE radcell AREA20080625 Nr 7
areamarginmerge
split
TEMPORAL EVOLUTION of ec-TRAM CELL PARAMETER
25 June 2008
Example rad-TRAM:
temporal evolution of selected parameters
radar-cell:-cell area [km²]
CASE STUDY
21
15
:30
15
:45
16
:00
16
:15
16
:30
16
:45
17
:00
17
:15
17
:30
17
:45
18
:00
18
:15
UTC timeCluster: time= 3 min, dist=3.0 km
0
100
200
300
400
500
600
[km
2],
[cn
t/ce
ll]
LIFE CYCLE licell with LIGHTNING FREQUENCY20080625 Nr 24
areaf(TOT)
f(IC)
f(CG)
margin
merge
split
25 June 2008
CASE STUDY
TEMPORAL EVOLUTION of ec-TRAM CELL PARAMETER
Example li-TRAM:
temporal evolution of selected parameters
lightning-cell: -cell area [km²]- TL
[cnt/cell]- CG
[cnt/cell]- IC
[cnt/cell]
22
22
TEMPORAL EVOLUTION of ec-TRAM CELL PARAMETER
Example ec-TRAM:
temporal evolution of selected parameters
radar-cell:-cell area [km²]
lightning-cell: -cell area [km²]- TL
[cnt/cell]- CG
[cnt/cell]- IC
[cnt/cell]
area
[km
²], d
isch
arg
e fr
equ
ency
[cn
t/ce
ll]
25 June 2008
CASE STUDY
23
23
TEMPORAL EVOLUTION of ec-TRAM CELL PARAMETER
area
[km
²], d
isch
arg
e fr
equ
ency
[cn
t/ce
ll]
onset
Example ec-TRAM:
temporal evolution of selected parameters
radar-cell:-cell area [km²]
lightning-cell: -cell area [km²]- TL
[cnt/cell]- CG
[cnt/cell]- IC
[cnt/cell]
CASE STUDY
24
24
TEMPORAL EVOLUTION of ec-TRAM CELL PARAMETER
area
[km
²], d
isch
arg
e fr
equ
ency
[cn
t/ce
ll]
cell splitting
Example ec-TRAM:
temporal evolution of selected parameters
radar-cell:-cell area [km²]
lightning-cell: -cell area [km²]- TL
[cnt/cell]- CG
[cnt/cell]- IC
[cnt/cell]
CASE STUDY
25
25
TEMPORAL EVOLUTION of ec-TRAM CELL PARAMETER
area
[km
²], d
isch
arg
e fr
equ
ency
[cn
t/ce
ll]
intensification
Example ec-TRAM:
temporal evolution of selected parameters
radar-cell:-cell area [km²]
lightning-cell: -cell area [km²]- TL
[cnt/cell]- CG
[cnt/cell]- IC
[cnt/cell]
CASE STUDY
26
26
TEMPORAL EVOLUTION of ec-TRAM CELL PARAMETER
area
[km
²], d
isch
arg
e fr
equ
ency
[cn
t/ce
ll]
decease
Example ec-TRAM:
temporal evolution of selected parameters
radar-cell:-cell area [km²]
lightning-cell: -cell area [km²]- TL
[cnt/cell]- CG
[cnt/cell]- IC
[cnt/cell]
CASE STUDY
27
VERIFICATION of LIGHTNING-CELL PROPERTIESin CASE-STUDIES
lifetime series of ec-cell parameters were complemented with 3D polarimetric radar data (POLDIRAD) - not shown
lightning-cell parameters were found to
-evolve reasonably according to the current state of knowledge-be in very good agreement with other case studies
[Klemp1987, Williams 1989 and 1999, Goodman 1988, Carey 1996, Lopez 1997, Mazur 1998, Altaraz 2003, Motley 2006, ...]
reflect the actual storm dynamic(intensification / weakening)li-TRAM has reasonable, consistent tracking performances(comparable to rad-TRAM)
[Meyer, 2010]
VERIFICATION
28
Lifetime = 40 min
30 May 2008lightning-cell No 137
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
PARAMETER CORRELATIONS of 2 LIGHTNING-CELL TRACKS
2 CASE STUDIES
29
Lifetime = 40 min
30 May 2008lightning-cell No 137
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
I
2
3
cell growth
PARAMETER CORRELATIONS of 2 LIGHTNING-CELL TRACKS
2 CASE STUDIES
30
Lifetime = 40 min
30 May 2008lightning-cell No 137
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
mature stage
PARAMETER CORRELATIONS of 2 LIGHTNING-CELL TRACKS
31
Lifetime = 40 min
30 May 2008lightning-cell No 137
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
4
5
6
E
cell dissipation
PARAMETER CORRELATIONS of 2 LIGHTNING-CELL TRACKS
2 CASE STUDIES
32
Lifetime = 145 min
25 May 2008lightning-cell No 6
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
PARAMETER CORRELATIONS of 2 LIGHTNING-CELL TRACKS
Lifetime = 40 min
30 May 2008lightning-cell No 137
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
2 CASE STUDIES
33
Lifetime = 145 min
25 May 2008lightning-cell No 6
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
23
45I
cell growth
PARAMETER CORRELATIONS of 2 LIGHTNING-CELL TRACKS
Lifetime = 40 min
30 May 2008lightning-cell No 137
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
2 CASE STUDIES
34
Lifetime = 145 min
25 May 2008lightning-cell No 6
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
mature stage
PARAMETER CORRELATIONS of 2 LIGHTNING-CELL TRACKS
Lifetime = 40 min
30 May 2008lightning-cell No 137
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
2 CASE STUDIES
35
Lifetime = 145 min
25 May 2008lightning-cell No 6
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
-2
E
-4-5
-6
cell dissipation
-3
PARAMETER CORRELATIONS of 2 LIGHTNING-CELL TRACKS
Lifetime = 40 min
30 May 2008lightning-cell No 137
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
2 CASE STUDIES
36
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
TL fit 1 + 2
TL fit 1 + 2
TL meanIC mean
PARAMETER MEANS
lightning frequency versus cell area
-10 km² area intervals-10 200 completely assessedlightning-cell entries
TL fit 1 + 2
TL fit 1 + 2
TL MEANIC MEAN
CORRELATION STATISTICS of LIGHTNING-CELL PARAMETERS
LIGHTNING-STATISTICS
37
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
TL fit 1 + 2
TL fit 1 + 2
TL meanIC mean
TL fit 1 + 2
TL fit 1 + 2
TL MEANIC MEAN
160 km²
CORRELATION STATISTICS of LIGHTNING-CELL PARAMETERS
LIGHTNING-STATISTICS
38
cell area [km²]IC m
ea
n d
isch
arg
e h
eig
ht p
er c
ell
[km
]
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
TL fit 1 + 2
TL fit 1 + 2
TL MEANIC MEAN fit 1 + 2
IC MEAN height
CORRELATION STATISTICS of LIGHTNING-CELL PARAMETERS
160 km²
LIGHTNING-STATISTICS
39
cell area [km²]IC m
ea
n d
isch
arg
e h
eig
ht p
er c
ell
[km
]
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
160 km²
fit 1 + 2IC mean height
160 km²
TL fit 1 + 2
TL fit 1 + 2
TL MEANIC MEAN fit 1 + 2
IC MEAN height
CORRELATION STATISTICS of LIGHTNING-CELL PARAMETERS
NO ARTIFACT of the ALGRITHM
LIGHTNING-STATISTICS
40
CORRELATION STATISTICS of LIGHTNING-CELL PARAMETERS
cell area [km²]IC m
ea
n d
isch
arg
e h
eig
ht p
er c
ell
[km
]
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
160 km²
TL fit 1 + 2
TL fit 1 + 2
TL meanIC mean fit 1 + 2
IC mean height
160 km²
NO INFORMATION about TEMPORAL CELL EVOLUTION
TL fit 1 + 2
TL fit 1 + 2
TL MEANIC MEAN fit 1 + 2
IC MEAN height
9LIGHTNING-STATISTICS
41
Lifetime = 40 min Lifetime = 145 min
30 May 2008lightning-cell No 137
25 May 2008lightning-cell No 6
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
I
EE
I
CORRELATION STATISTICS of LIGHTNING-CELL PARAMETERS
10LIGHTNING-STATISTICS
42
Lifetime = 40 min Lifetime = 145 min
30 May 2008lightning-cell No 137
25 May 2008lightning-cell No 6
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
I
EE
I
CORRELATION STATISTICS of LIGHTNING-CELL PARAMETERS
10LIGHTNING-STATISTICS
43
FREQUENCY DISTRIBUTION of LIFE-TIMES
LIGHTNING-STATISTICS
lightning-cell lifetime [min]
fre
que
ncy
[-] long-lived cellsshort-lived cells
44
LIFETIME REGIMES
LIGHTNING-STATISTICS
short-lived [ 15 min – 75 min ]
‚SINGLE CELLS‘- lowly organized- simply structured: 1 updraft + 1 downdraft- simple life-cycles: growth – short maturity – decease
long-lived [ ≥ 80 min ]
‚MULITCELLS‘, ‚SUPERCELLS‘- highly organized- complexly structured- complex life-cycles: growth – elongated (fluctuating) maturity – decease
45
rela
tive
fre
que
ncy
cell area [km²]cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
total lightning
short-lived
long-lived cells
RELATIVE AMOUNT to STATISTICAL MEAN
CORRELATION STATISTICS of LIGHTNING-CELL PARAMETERS
LIGHTNING-STATISTICS
46
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell] total lightning
cell type
growth
decease
CORRELATION STATISTICS of LIGHTNING-CELL PARAMETERS
short-lived cells
short-lived
DISCUSSION
47
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell] total lightning
cell type
long-lived cells
maturity
CORRELATION STATISTICS of LIGHTNING-CELL PARAMETERS
long-lived cells
growth
decease
DISCUSSION
4848
cell area [km²]
Lig
htn
ing
freq
ue
ncy
pe
r ce
ll [1
/km
²]
TL fit 1 + 2
TL fit 1 + 2
TL meanIC mean
SCATTER!
total lightning
cell area [km²]IC m
ea
n d
isch
arg
e h
eig
ht p
er c
ell
[km
]
fit 1 + 2IC mean height
SCATTER!
CORRELATION STATISTICS of LIGHTNING-CELL PARAMETERS
DISCUSSION
49
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
long-livedcell type
long-lived cells
short-lived
short-lived
INFORMATION about STORM TYPE (lifetime, intensity) and TEMPORAL EVOLUTION!
CORRELATION STATISTICS of LIGHTNING-CELL PARAMETERS
DISCUSSION
50
THUNDERSTORM TRACKING and NOWCASTING
cell track
MUNICH AIRPORT
lightning-cell
cell nowcasts
14:45 15:00 15:15 15:30
total lightningcloud lightningcloud-to-groundlightning
time
now prognosis
temporal evolution of LIGHTNING cell parameters
Ad MOTIVATION
51
cell area [km²]IC m
ea
n d
isch
arg
e h
eig
ht p
er c
ell
[km
]
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
TL fit 1 + 2
TL fit 1 + 2
TL MEANIC MEAN fit 1 + 2
IC MEAN height
3D informationfrom
2D cell tracking!
CORRELATION STATISTICS of LIGHTNING-CELL PARAMETERS
DISCUSSION
52
GOAL:
to assess the usability of 3D total-lightning data for thunderstorm nowcasting separately and in combination with other data sources (radar)
CONCLUSION
11CONCLUSION and OUTLOOK
3D lightning information with in-cloud and cloud-to-ground lightning discrimination provides useful information about the storm dynamic and developement and have the capacity to nowcast cell trends from the cell history
53
- test the usability of (specified) normalized cell life-cycles to derive trend prognoses
- use cell trends from cell history to add trend prognoses to local prognoses
- test the quality of trend prognoses
- investigate cell parameter correlations with other data sources (3D radar, satellite, ...)
OUTLOOK
11CONCLUSION and OUTLOOK
54
- parameterization of TL frequency with IC/CG ratio and mean IC height for modelling [Price and Rind 1992, Allen and Pickering 2002]
- simulation of thunderstorm life-cycles with realistic discharge characteristics
OTHER possible APPLICATIONS
CONCLUSION and OUTLOOK
?160 km²?
55
cell area [km²]IC m
ea
n d
isch
arg
e h
eig
ht p
er c
ell
[km
]
cell area [km²]
ligh
tnin
g fr
equ
ency
pe
r ce
ll [c
nt/c
ell]
160 km²
TL fit 1 + 2
TL fit 1 + 2
TL meanIC mean fit 1 + 2
IC mean height
160 km²
THANK YOU
56
Literature
K. Kober and A. Tafferner. Tracking and nowcasting of convective cells unsing remote sensing data from radar and satellite. Meteorologiesche Zeitschrift, 10(1):75-84, 2009
V. Meyer, H. Höller, K.Schmidt, and H.-D. Betz. Temporal evolution of total lightning and radar parameters of thunderstorms in southern Germany and its benefit for nowcasting. Proceedings: 5th European Conference on Severe Storms, 2009
V. Meyer (2010): Thunderstorm Tracking and Monitorin on the Basis of Three Dimenional Lightning Data and Conventional and Polarimetric Radar Data. Dissertation, LMU München: Faculty of Physicshttp://edoc.ub.uni-muenchen.de/12102/
57
57
POLARIMTRIC INFORMATION
POLDIRAD RHI 20080625, hydrometeorclassifications, 16:42h, azimuth = 52 °
sounding munich: 0 ° at 3.5 km, Tropopause at 10 km
58
area
[km
²],
dis
char
ge
freq
uen
cy [
cnt/
cell
]
25 June 2008example:
radar-cell:-cell area [km²]
lightning-cell: -cell area [km²]- TL [cnt/cell]- CG [cnt/cell]- IC [cnt/cell]
polar. radar data
- hydrometeors
ZEITLICHE ENTWICKLUNG VON ec-ZELL PARAMETERN
dBZ cellgraupel/hail
heavy rainlight rain H = 4 km
ground