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Forecast Products User Meeting June 2006
Slide 1
Slide 1
ECMWF medium-range forecasts and products
David Richardson
Met Ops Section, Jean Bidlot, Mark Rodwell, Roberto Buizza
Forecast Products User Meeting June 2006
Slide 2
Slide 2
Atmospheric data assimilation
4-dimensional variational data assimilation at 25/80 km resolution and 91 levels
Atmospheric global forecasts
Forecast to ten days from 00 and 12 UTC at 25 km resolution and 91 levels
50-member ensemble to ten days from 00 and 12 UTC at 50 km resolution, 62 levels
Ocean wave forecasts
Global forecast to ten days from 00 and 12 UTC at 50 km resolution
European waters forecast to five days from 00 and 12 UTC at 25 km resolution
Monthly forecasts: Atmosphere-ocean coupled model
Global ensemble to one month (weekly) 125 km, 62 level atmosphere; 1°, 29 level ocean
Seasonal forecasts: Atmosphere-ocean coupled model
Global ensemble to six months (monthly): 200 km, 40 level atmosphere; 1°, 29 level ocean
ECMWF Operational Forecast System
Forecast Products User Meeting June 2006
Slide 3
Slide 3
Changes to the forecasting system 2005 – 2006
5 Apr 2005 Cy29r1New moist boundary layer scheme, wavelet
Jb, adaptive bias correction
28 Jun 2005 Cy29r2Wide range of changes including rain-
affected SSM/I radiances
1 Feb 2006 Cy30r1High resolution forecasting system
Harmonisation of data availability times
14 Mar 2006 4d-Var for all BC suite analyses
Forecast Products User Meeting June 2006
Slide 4
Slide 4
Medium-range forecast performance
Forecast Products User Meeting June 2006
Slide 5
Slide 5
Time series Acc=0.6 N Hemisphere
Forecast Products User Meeting June 2006
Slide 6
Slide 6
Time series Acc=0.6 S Hemisphere
Forecast Products User Meeting June 2006
Slide 7
Slide 7
Time series Acc=0.6 Europe
Forecast Products User Meeting June 2006
Slide 8
Slide 8
Spring 2006 (MAM) over Europe
Forecast Products User Meeting June 2006
Slide 9
Slide 9
Comparison with other centres
Forecast Products User Meeting June 2006
Slide 10
Slide 10
Time series Z500 N Hemisphere
Forecast Products User Meeting June 2006
Slide 11
Slide 11
Time series Z500 N Hemisphere
Forecast Products User Meeting June 2006
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Slide 12
Other centres Z500 N hem 2006 v 2005
Forecast Products User Meeting June 2006
Slide 13
Slide 13
Other centres Z500 Europe 2006 v 2005
Forecast Products User Meeting June 2006
Slide 14
Slide 14
Consistency of high resolution forecast
Forecast Products User Meeting June 2006
Slide 15
Slide 15
Forecast consistency
Forecast Products User Meeting June 2006
Slide 16
Slide 16
Forecast consistency
Forecast Products User Meeting June 2006
Slide 17
Slide 17
Forecast consistency
Forecast Products User Meeting June 2006
Slide 18
Slide 18
Weather parameters – this afternoon
Forecast Products User Meeting June 2006
Slide 19
Slide 19
Waves
Forecast Products User Meeting June 2006
Slide 20
Slide 20
Wave analysis – scatter index
Forecast Products User Meeting June 2006
Slide 21
Slide 21
Wave forecast – scatter index
Forecast Products User Meeting June 2006
Slide 22
Slide 22
Waves – other centres
Forecast Products User Meeting June 2006
Slide 23
Slide 23
Ensemble Prediction System- this afternoon (Roberto Buizza)
Forecast Products User Meeting June 2006
Slide 24
Slide 24
Brier Skill Score for Europe for 96h EPS forecast of precipitation exceeding various thresholds
Forecast Products User Meeting June 2006
Slide 25
Slide 25
12UTCN.hem Lat 20.0 to 90.0 Lon -180.0 to 180.0
500hPa GeopotentialTime series curves
MAR2005
APR MAY JUN JUL4
6
8
10
12
14
16
18
20
22
24
ENSTD T+24 Mean forecast
ENSTD T+48 Mean forecast
ENSMN T+24 rmse forecast
ENSMN T+48 rmse forecast
A diagnostics for the EPS spread (standard deviation of Gaussian) is now available on the internal web site. Problems similar to the one in May 2005 could be identified and corrected
EPS spread/skill
Forecast Products User Meeting June 2006
Slide 26
Slide 26
0
3
6
9
12
15
18
ST
D
0
3
6
9
12
15
18
OCT
2005
12 14 16 18 20 22 24 26 28 30 1NOV
3 5 7 9 11 13 15 17 19 21 23 25 27 29 1DEC
3 5 7 9
initialStandard deviation of Gaussian -- exp: 0001
N.Hemisphere S.Hemisphere
Diagnostic tool:
Standard deviation of gaussian
problematic forecast
Forecast Products User Meeting June 2006
Slide 27
Slide 27
0 1 2 3 4 5 6 7 8 9 10
Forecast Day
516
528
540
552
564
576dam
GEOPOTENTIAL 500hPa - Probability for 2.5 dam intervals Range: 72dam
Exp 0001
0 1 2 3 4 5 6 7 8 9 10
Forecast Day
0
2
4
6
8
10
12
14mm
Ensemble members of TOTAL PRECIPITATION - Accum. rate mm/12h
0 1 2 3 4 5 6 7 8 9 10
Forecast Day
-5
0
5
10deg
TEMPERATURE 850hPa - Probability for 1.0 deg intervals Range: 20deg
DATE: 20051125 READING LAT: 51.45 LONG: -0.95ECMWF ENSEMBLE FORECASTS FOR: ECMWF 0.5 - 10 % 10 - 30 % 30 - 50 % 50 - 100 %
Oper T255 Anal EMem
Reading plume for 20051125 00UTC run
Forecast Products User Meeting June 2006
Slide 28
Slide 28
Future developments
Forecast Products User Meeting June 2006
Slide 29
Slide 29
VAREPS (2006)
Plan to extend forecast range of EPS to day 15
Two additional fixed-resolution calibration forecasts will be run
Current products to day 10 will be unaffected
T799 deterministic will remain as now (days 1-10 only)
# fc day 0-10 day 10-15
VAR-CF 1 TL399 TL255
VAR-PF 50 TL399 TL255
CL-HRES 1 TL399
CL-LRES 1 TL255
Forecast Products User Meeting June 2006
Slide 30
Slide 30
VAREPS
Initial implementation No changes required to access products to day 10
Individual EPS members archived to day 15
Straightforward to access days 10-15 (note resolution change at day 10!)
No change required to MARS requests or EMOSLIB (current version: cy281)
First post-processed products Ensemble mean and spread (standard deviation) to day 15
• Calculate on model grid (was 1.5 degree lat-lon)
Probabilities extended to day 15 (same thresholds as now)
Longer term EPS products to day 15 will be developed
15-day VAREPS will be combined with the monthly system (coupling with ocean model)
Forecast Products User Meeting June 2006
Slide 31
Slide 31
Products
Forecast Products User Meeting June 2006
Slide 32
Slide 32
ECMWF Forecast Products
Global forecasts (deterministic)
Fields (Model variables, GRIB)
Time series (BUFR Meteograms)
Direct Model Output (DMO) only
EPS
Fields (GRIB) + Time Series (BUFR EPSGRAMs)
Post-processed products (Clusters, Tubes, EFI)
Monthly and seasonal forecasts: atmosphere-ocean coupled model
Anomalies (Field + Time series)
Forecast Products User Meeting June 2006
Slide 33
Slide 33
EPS forecasts: timeseries (EPSgram)
EPSgram for Reading
Base Tue 14/06/06 00UTC
Forecast Products User Meeting June 2006
Slide 34
Slide 34
EPS forecasts (post-processed products)
Extreme forecast index for 2m temperature
Base Sat 10/06/06 00UTC, Valid Wed 14/06/06 12UTC
Forecast Products User Meeting June 2006
Slide 35
Slide 35
Medium-range forecast products
Global Extreme Forecast Index
Indicates areas where today’s EPS has signal of extreme relative to model climate distribution
New EFI climatology introduced with high-resolution system
Verification against observations has started
More this afternoon
Tropical cyclone tracks
More realistic structure in higher resolution system
Indication of reduction in position and intensity errors
2006 Atlantic season started (Alberto) …
EPSgrams – combine deterministic and EPS forecasts
Forecast Products User Meeting June 2006
Slide 36
Slide 36
Tropical Storm Alberto
Forecast Products User Meeting June 2006
Slide 37
Slide 37
948
T511 L60 20050828 00UTC ECMWF FC t+36 VT: 20050829 12UTC Surf: MSL
942
T799 L91 20050828 00UTC ECMWF FC t+36 VT: 20050829 12UTC Surf: MSL
963
T511 L60 20050826 12UTC ECMWF FC t+72 VT: 20050829 12UTC Surf: MSL
944
T799 L91 20050826 12UTC ECMWF FC t+72 VT: 20050829 12UTC Surf: MSL
Forecasts of Katrina for Monday 29 Aug. 12 UTCobserved pressure 922 hPa
T511 T799
t+36 t+36
t+72 t+72
Forecast Products User Meeting June 2006
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Slide 38
0
200
400
600
800
km
0 24 48 72 96 120
forecast step
0
40
80
120
160
sa
mp
le s
ize
0 24 48 72 96 120
forecast step
0001 vs. 002817 Jul until 18 Aug
years: 2005 oper
Direct Position Error
281
Position error in high resolution T799 is smaller at all forecast steps compared to the T511.
T511L60
T799L91
Deterministic Scores – T511 vs T799
Forecast Products User Meeting June 2006
Slide 39
Slide 39
-20
0
20
40
hP
a
0 24 48 72 96 120
forecast step
0
40
80
120
160
sa
mp
le s
ize
0 24 48 72 96 120
forecast step
0001 vs. 002817 Jul until 18 Aug
years: 2005 oper
Core Pressure Error
281
The intensity of tropical cyclones is more realistic in the T799.
T511L60
T799L91
Deterministic Scores – T511 vs T799
Forecast Products User Meeting June 2006
Slide 40
Slide 40
Combined prediction system developmentMark Rodwell
Forecast Products User Meeting June 2006
Slide 41
Slide 41
Highly useful product but…• What should I believe?
• At D+2• At D+5
CPS - Motivation
Thu 1 Fri 2 Sat 3 Sun 4 Mon 5 Tue 6 Wed 7 Thu 8 Fri 9 Sat 10June 2006
22
24
26
28
30
32
max
min
75%median25% T799 OPS T399 CTRL
2m Temperature reduced to station height (°C) 28m (T799) 26m (T399)
Magics++ 1.1.0
0
2
4
6
8
1010m Wind Speed (m/s)
0
2
4
6
8
10
12
14
16Total Precipitation (mm/6h)
0
2
4
6
8
EPS MeteogramMumbai (26m) 19.1°N 72.9°EDeterministic Forecasts and EPS Distribution Thursday 1 June 2006 00 UTC
Total Cloud Cover (okta)
Thu 1 Fri 2 Sat 3 Sun 4 Mon 5 Tue 6 Wed 7 Thu 8 Fri 9 Sat 10June 2006
22
24
26
28
30
32
max
min
75%median25% T799 OPS T399 CTRL
2m Temperature reduced to station height (°C) 28m (T799) 26m (T399)
Magics++ 1.1.0
0
2
4
6
8
1010m Wind Speed (m/s)
0
2
4
6
8
10
12
14
16Total Precipitation (mm/6h)
0
2
4
6
8
EPS MeteogramMumbai (26m) 19.1°N 72.9°EDeterministic Forecasts and EPS Distribution Thursday 1 June 2006 00 UTC
Total Cloud Cover (okta)
Mumbai
Forecast Products User Meeting June 2006
Slide 42
Slide 42
CPS – Concept
Combining a 10-member ensemble of equally likely members (orange squares) with a single more accurate forecast (yellow rectangle)
Forecast Products User Meeting June 2006
Slide 43
Slide 43
1 2 3 4 5 6 7 8 9 10Lead-time (days)
0.0
0.1
0.2
0.3
0.4
Bri
er S
kill
Sco
reBrier Skill Score for the event that P
p > x mm day-1
x=1
CPS
EPS
x=5
CPS
EPS
x=10
CPS
EPS
CPS > EPS
5% Significance
CPS – Results
2001-2005
Forecast Products User Meeting June 2006
Slide 44
Slide 44
1 2 3 4 5 6 7 8 9 10Lead-time (days)
0
5
10
15
20
Wei
gh
t (n
um
ber
of
EP
S m
emb
ers)
Weight of Deterministic Forecast within Combined Prediction System
Pp > 1 mm day-1
Pp > 5 mm day-1
Pp > 10 mm day-1
CPS – Weights
2001-2005
Forecast Products User Meeting June 2006
Slide 45
Slide 45
Thu 1 Fri 2 Sat 3 Sun 4 Mon 5 Tue 6 Wed 7 Thu 8 Fri 9 Sat 100
20
40
60
Total Precipitation (mm/day) Combined Probability DistributionsOptimized for the critical event the precipitation exceeds 1 mmday-1
Prob > 1 mm/day
Brier Skill Score
100
33
100
34
100
31
100
26
100
19
100
12
100
7
94
2
98
0
94
0
CPS – Meteogram
Mumbai
Forecast Products User Meeting June 2006
Slide 46
Slide 46
Thu 1 Fri 2 Sat 3 Sun 4 Mon 5 Tue 6 Wed 7 Thu 8 Fri 9 Sat 100
20
40
60
Total Precipitation (mm/day) Combined Probability DistributionsOptimized for the critical event the precipitation exceeds 10 mmday-1
Prob > 10 mm/day
Brier Skill Score
100
23
98
19
91
14
70
9
90
5
81
1
45
0
27
0
27
0
43
0
CPS – Meteogram
Mumbai
Forecast Products User Meeting June 2006
Slide 47
Slide 47
ECMWF visits to Member and Co-operating StatesAutumn 2005 – spring 2006
Forecast Products User Meeting June 2006
Slide 48
Slide 48
Member State visits – comments (1)
Generally very happy with ECMWF products
High resolution system introduced halfway through this round of visits
How is consistency of T799 model?
• No significant change from previous model
ECMWF boundary conditions for limited area models
Some requests for hourly updates (currently 3-hourly)
• Discussed at TAC BC subgroup and TAC 2005; agreed not to change
High-impact weather early warnings (medium-range)
We are still interested in feedback and examples, especially of how ECMWF products may be useful
Forecast Products User Meeting June 2006
Slide 49
Slide 49
Member State visits – comments (2)
Big range of use for the EPS (internal; specific users; general public)
Clusters –
• some use ECWF clusters, some do own clustering
• ECMWF clustering needs updating
• Request for extra area
EPSgrams – noted requests for additional parameters (H/M/L cloud, wind)
How should the EPS be used?
How can EPS be used together with T799?
Increasing interest in monthly forecasts
Interest in potential of seasonal forecasts