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Monthly Forecasting with Ensembles. Fr é d é ric Vitart European Centre for Medium-Range Weather Forecasts. Index. The ECMWF monthly forecasting system Description Skill Some sources of predictability in the subseasonal time-scale Madden Julian Oscillation Stratospheric Sudden Warming - PowerPoint PPT Presentation
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Exeter 1-3 December 2010
Monthly Forecasting with Ensembles
Frédéric Vitart European Centre for Medium-Range Weather Forecasts
Exeter 1-3 December 2010
Index
• The ECMWF monthly forecasting system Description Skill
• Some sources of predictability in the subseasonal time-scale Madden Julian Oscillation Stratospheric Sudden Warming Soil moisture
• Extension to 46-day – Comparison with seasonal forecasts
Exeter 1-3 December 2010
Product
ECMWF:Weather and Climate Dynamical Forecasts
ECMWF:Weather and Climate Dynamical Forecasts
Medium-Range Forecasts
Day 1-10(15)
Medium-Range Forecasts
Day 1-10(15)
MonthlyForecast
Day 10-32
MonthlyForecast
Day 10-32
Seasonal Forecasts
Month 2-7
Seasonal Forecasts
Month 2-7
Forecasting systems at ECMWF
Exeter 1-3 December 2010
Ocean only integration
Coupled forecast at TL319Day 32
EPS Integration at T639
Initial condition
Heat flux, Wind stress, P-E
Current system (once a week, 51 ensemble members):
The ECMWF VarEPS-monthly forecasting system
Day 10
Exeter 1-3 December 2010
The ECMWF monthly forecasting system
• Background statistics:
5-member ensemble integrated at the same day and same month as the real-time time forecast over the past 18 years (a total of 90 member ensemble)
Initial conditions: ERA Interim
It runs once every week
Exeter 1-3 December 2010
The ECMWF monthly forecasting system
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
70°N 70°N
20°W
20°W 0°
0° 20°E
20°E 40°E
40°E
ensemble size = 51 ,climate size = 90Forecast start reference is 25-11-2010(Prob 2m Temp. anom below 33%)ECMWF EPS-Monthly Forecasts
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
70°N 70°N
20°W
20°W 0°
0° 20°E
20°E 40°E
40°E
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
70°N 70°N
20°W
20°W 0°
0° 20°E
20°E 40°E
40°E
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
70°N 70°N
20°W
20°W 0°
0° 20°E
20°E 40°E
40°E
DAY 5-11: 29-11-2010/TO/05-12-2010 DAY 12-18 :06-12-2010/TO/12-12-2010
DAY 19-25 :13-12-2010/TO/19-12-2010 DAY 26-32:20-12-2010/TO/26-12-2010
< 10% 10.. 20 20.. 40 40.. 50 50.. 60 60.. 70 > 70%
Exeter 1-3 December 2010 7
Problem with hindcast initial conditions
Probability of T2m to be in lowest tercile
100 %0
Forecast of week 1Start: 11-05-2006
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006YEAR
0
0.005
0.01
0.015
Sno
w d
epth
in m
eter
s
SNOW DEPTH (m)0-10E, 40N-50N
Snow ANALYSIS 11 MAY
Observations
Exeter 1-3 December 2010
Skill of the ECMWF Monthly Forecasting System
ROC score: 2-meter temperature in the upper tercile
Day 19-25 Day 26-32
Day 5-11 Day 12-18
80°S80°S
70°S 70°S
60°S60°S
50°S 50°S
40°S40°S
30°S 30°S
20°S20°S
10°S 10°S
0°0°
10°N 10°N
20°N20°N
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
70°N 70°N
80°N80°N
160°W
160°W 140°W
140°W 120°W
120°W 100°W
100°W 80°W
80°W 60°W
60°W 40°W
40°W 20°W
20°W 0°
0° 20°E
20°E 40°E
40°E 60°E
60°E 80°E
80°E 100°E
100°E 120°E
120°E 140°E
140°E 160°E
160°E
20041007 TO 20090205DAY 12-18ROC SCORE : 2-meter temperature in upper tercileECMWF Monthly Forecasting System
<0.1 0.1..0.2 0.2..0.3 0.3..0.4 0.4..0.5 0.5..0.6 0.6..0.7 0.7..0.8 0.8..0.9 > 0.9
80°S80°S
70°S 70°S
60°S60°S
50°S 50°S
40°S40°S
30°S 30°S
20°S20°S
10°S 10°S
0°0°
10°N 10°N
20°N20°N
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
70°N 70°N
80°N80°N
160°W
160°W 140°W
140°W 120°W
120°W 100°W
100°W 80°W
80°W 60°W
60°W 40°W
40°W 20°W
20°W 0°
0° 20°E
20°E 40°E
40°E 60°E
60°E 80°E
80°E 100°E
100°E 120°E
120°E 140°E
140°E 160°E
160°E
20041007 TO 20090205DAY 5-11ROC SCORE : 2-meter temperature in upper tercileECMWF Monthly Forecasting System
<0.1 0.1..0.2 0.2..0.3 0.3..0.4 0.4..0.5 0.5..0.6 0.6..0.7 0.7..0.8 0.8..0.9 > 0.9
80°S80°S
70°S 70°S
60°S60°S
50°S 50°S
40°S40°S
30°S 30°S
20°S20°S
10°S 10°S
0°0°
10°N 10°N
20°N20°N
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
70°N 70°N
80°N80°N
160°W
160°W 140°W
140°W 120°W
120°W 100°W
100°W 80°W
80°W 60°W
60°W 40°W
40°W 20°W
20°W 0°
0° 20°E
20°E 40°E
40°E 60°E
60°E 80°E
80°E 100°E
100°E 120°E
120°E 140°E
140°E 160°E
160°E
20041007 TO 20090205DAY 19-25ROC SCORE : 2-meter temperature in upper tercileECMWF Monthly Forecasting System
<0.1 0.1..0.2 0.2..0.3 0.3..0.4 0.4..0.5 0.5..0.6 0.6..0.7 0.7..0.8 0.8..0.9 > 0.9
80°S80°S
70°S 70°S
60°S60°S
50°S 50°S
40°S40°S
30°S 30°S
20°S20°S
10°S 10°S
0°0°
10°N 10°N
20°N20°N
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
70°N 70°N
80°N80°N
160°W
160°W 140°W
140°W 120°W
120°W 100°W
100°W 80°W
80°W 60°W
60°W 40°W
40°W 20°W
20°W 0°
0° 20°E
20°E 40°E
40°E 60°E
60°E 80°E
80°E 100°E
100°E 120°E
120°E 140°E
140°E 160°E
160°E
20041007 TO 20090205DAY 26-32ROC SCORE : 2-meter temperature in upper tercileECMWF Monthly Forecasting System
<0.1 0.1..0.2 0.2..0.3 0.3..0.4 0.4..0.5 0.5..0.6 0.6..0.7 0.7..0.8 0.8..0.9 > 0.9
80°S80°S
70°S 70°S
60°S60°S
50°S 50°S
40°S40°S
30°S 30°S
20°S20°S
10°S 10°S
0°0°
10°N 10°N
20°N20°N
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
70°N 70°N
80°N80°N
160°W
160°W 140°W
140°W 120°W
120°W 100°W
100°W 80°W
80°W 60°W
60°W 40°W
40°W 20°W
20°W 0°
0° 20°E
20°E 40°E
40°E 60°E
60°E 80°E
80°E 100°E
100°E 120°E
120°E 140°E
140°E 160°E
160°E
20041007 TO 20090205DAY 5-11ROC SCORE : 2-meter temperature in upper tercileECMWF Monthly Forecasting System
<0.1 0.1..0.2 0.2..0.3 0.3..0.4 0.4..0.5 0.5..0.6 0.6..0.7 0.7..0.8 0.8..0.9 > 0.9
Exeter 1-3 December 2010 9
Monthly Forecast: Performance over the Northern Extratropics
Forecast Day 12-18
Persistence of Day 5-11
Forecast Day 19-32
Persistence of Day 5-18
ROC score: 2-meter temperature in the upper tercile
2005 2006 2007 2008 2009 2010YEAR
0.4
0.5
0.6
0.7
0.8
RO
C S
Cor
e
2005 2006 2007 2008 2009 2010YEAR
0.4
0.5
0.6
0.7
0.8
RO
C S
Cor
e
Day 12-18 Day 19-32
Exeter 1-3 December 2010
The Madden Julian Oscillation
Exeter 1-3 December 2010
OLR anomalies - Forecast range: day 15
32R3
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
ERA40
10
-10
-1 0 -10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/02
31/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/01
31/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
Ensemble meanewku
-10
-10
-10
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/02
31/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/01
31/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
Ensemble meanex6i
-10
-10
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/02
31/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/01
31/1230/1229/12
ERA40
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
ERA40
10
-10
-10
-10
-10 -10-10
-10
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/02
31/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/01
31/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
Ensemble meanewku
10
-10
-10
-10
-10
-10
-10
-10
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/02
31/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/01
31/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
Ensemble meanex6i
-10
-10
-10
-10
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/02
31/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/01
31/1230/1229/12
days
29/12
05/01
12/01
20/01
28/01
04/04
12/02
28R3 29R1 31R1 32R2
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
ERA40
10
-10
-10
-10
-10 -10
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/02
31/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/01
31/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
Ensemble meanewku
-10
-10
-10
-10
-10
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/02
31/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/01
31/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
Ensemble meanex6i
-10
-10
-10
-10
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/02
31/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/01
31/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
ERA40
10
-10
-10
-10
-10 -10
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/02
31/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/01
31/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
Ensemble meanelz5
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/02
31/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/01
31/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
Ensemble meanek7h
-10
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/02
31/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/01
31/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
ERA40
10
-10
-10
-10
-10 -10-10
-10
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/02
31/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/01
31/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
Ensemble meanelz5
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/02
31/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/01
31/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
Ensemble meanek7h
-10
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/02
31/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/01
31/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
ERA40
10
-10
-10
-10
-10 -10
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/0231/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/0131/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
Ensemble meanes8c
-10
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/0231/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/0131/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
Ensemble meaner98
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/0231/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/0131/1230/1229/12
10/04 04/05 09/06 06/07
11/07
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
ERA40
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/0231/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/0131/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
Ensemble meanf4i5
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/0231/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/0131/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
Ensemble meanf1xi
10
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/0231/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/0131/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
ERA40
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/0231/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/0131/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
Ensemble meanf4i5
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/0231/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/0131/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
Ensemble meanf1xi
10
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/0231/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/0131/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
ERA40
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/0231/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/0131/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
Ensemble meanf46n
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/0231/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/0131/1230/1229/12
30
25
20
15
10
5
0
DA
YS
30E 90E 150E 150W 90W 30W
LONGITUDE
30E 90E 150E 150W 90W 30W
Ensemble meanf6ju
10
-10
-10
-10
15/0214/0213/0212/0211/0210/02 9/02 8/02 7/02 6/02 5/02 4/02 3/02 2/02 1/0231/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 9/01 8/01 7/01 6/01 5/01 4/01 3/01 2/01 1/0131/1230/1229/12
33R1 35R1 35R3
06/08 09/08 09/09
Exeter 1-3 December 2010
Experimental setup:
- 46 day hindcasts at T399/T255. Coupled after day 10.
- 15 members
- Starting dates: 1st of each month 1989-2008
- Model Cycle 32R3 (operational cycle from 11/07 to 06/08)
Hindcast Experiment
Exeter 1-3 December 2010
“Perfect Model”
Ensemble mean/ reanalysis
MJO Skill scores
Bivariate Correlation Bivariate RMS error
0 5 10 15 20 25 30 35 40 45Time Lag (days)
0
0.2
0.4
0.6
0.8
1
Correla
tion
Ensemble Spread
0 5 10 15 20 25 30 35 40 45Time Lag (days)
0
0.5
1
1.5
RM
S E
rror
Ensemble mean/ reanalysis
Climatology
Exeter 1-3 December 2010
Impact on the Extratropics- Z500 anomalies
MODEL Phase 3 + 10 days ERA Phase 3 + 10 days
MODEL Phase 6 + 10 days ERA Phase 6 + 10 days
Exeter 1-3 December 2010
500hPa GeopotentialTuesday 15 January 1991 00UTC ECMWF EPS Control Forecast t+0 VT: Tuesday 15 January 1991 00UTC
-100-95-90-85-80-75-70-65-60-55-50-45-40-35-30-25-20-15-10-551015202530354041.19
500hPa GeopotentialTuesday 15 January 1991 00UTC ECMWF EPS Control Forecast t+0 VT: Tuesday 15 January 1991 00UTC
-100-95-90-85-80-75-70-65-60-55-50-45-40-35-30-25-20-15-10-55101520253035404548.11
ECMWF Analysis VT:Friday 15 November 1991 00UTC 500hPa Geopotential
-100-95-90-85-80-75-70-65-60-55-50-45-40-35-30-25-20-15-10-551015202530354041.48
500hPa GeopotentialTuesday 15 January 1991 00UTC ECMWF EPS Control Forecast t+0 VT: Tuesday 15 January 1991 00UTC
-100-95-90-85-80-75-70-65-60-55-50-45-40-35-30-25-20-15-10-551015202526.89
ERA Interim 32R3
36R1 36R1_relax
Impact on the Extratropics- Z500 anomalies
Exeter 1-3 December 2010
Phase3+10 days
1 2 3 4-30
-20
-10
0
10
20
30
Impact on weather regimes
NAO- NAO+ Atlantic ridge
Scandinavian blocking
Phase6+10 days
Exeter 1-3 December 2010
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1forecast probability
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
obs
freq
uen
cy
0.04
Probabilistic skill scores – NDJFMA 1989-2008
Reliability DiagramProbability of 2-m temperature in the upper tercile
Day 19-25
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1forecast probability
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
obs
freq
uen
cy
Europe
0.03
-0.09
Strong MJO in IC Weak MJO in IC
N. Extratropics
-0.06
Exeter 1-3 December 2010
Impact of the MJO on Brier Skill ScoresNDJFMA 1989-2008- N. Extratropics
0 1 2 3 40
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
MAGICS 6.12 vancleef - nec Fri Aug 27 11:38:51 2010
DAY 5-11
Z500 T850 Precip
DAY 12-18
Z500 T850 Precip
DAY 19-25 DAY 26-32
0 1 2 3 4-0.1
-0.08
-0.06
-0.04
-0.02
0
0.02
0.04
0.06
0.08
0.1
MAGICS 6.12 vancleef - nec Fri Aug 27 12:56:10 2010Z500 T850 Precip Z500 T850 Precip0 1 2 3 4
-0.1
-0.08
-0.06
-0.04
-0.02
0
0.02
0.04
MAGICS 6.12 vancleef - nec Fri Aug 27 13:12:47 2010
0 1 2 3 4
-0.08
-0.04
0
0.04
0.08
0.12
0.16
0.2
MAGICS 6.12 vancleef - nec Fri Aug 27 13:21:37 2010
Weak MJO in IC Strong MJO in IC
Exeter 1-3 December 2010
MJO Composite- NDJFMA
Tropical storm density anomaly
Vitart, 2009, GRL
Exeter 1-3 December 2010
Tropical storm strike probability
WEEK 1 Week 2 Week 3
Weak MJO 0.78 0.72 0.68
Strong MJO 0.87 0.79 0.74
80°N
70°N
60°N
50°N
40°N
30°N
20°N
10°N
0°N
10°S
20°S
30°S
40°S
50°S
60°S
70°S
80°S
80°N
70°N
60°N
50°N
40°N
30°N
20°N
10°N
0°N
10°S
20°S
30°S
40°S
50°S
60°S
70°S
80°S
340°E320°E300°E280°E260°E240°E220°E200°E180°E160°E140°E120°E100°E80°E60°E40°E20°E
340°E320°E300°E280°E260°E240°E220°E200°E180°E160°E140°E120°E100°E80°E60°E40°E20°E
< 10% 10.. 20 20.. 30 30.. 40 40.. 50 50.. 60 60.. 70 70.. 80 80.. 90 > 90%
Probability of a TS passing within 300km radiusWeekly mean Tropical Storm Strike Probability. Date: 20101122 0 UTC t+( 96-264)
80°N
70°N
60°N
50°N
40°N
30°N
20°N
10°N
0°N
10°S
20°S
30°S
40°S
50°S
60°S
70°S
80°S
80°N
70°N
60°N
50°N
40°N
30°N
20°N
10°N
0°N
10°S
20°S
30°S
40°S
50°S
60°S
70°S
80°S
340°E320°E300°E280°E260°E240°E220°E200°E180°E160°E140°E120°E100°E80°E60°E40°E20°E
340°E320°E300°E280°E260°E240°E220°E200°E180°E160°E140°E120°E100°E80°E60°E40°E20°E
< 10% 10.. 20 20.. 30 30.. 40 40.. 50 50.. 60 60.. 70 70.. 80 80.. 90 > 90%
Probability of a TS passing within 300km radiusWeekly mean Tropical Storm Strike Probability. Date: 20101122 0 UTC t+(264-432)
80°N
70°N
60°N
50°N
40°N
30°N
20°N
10°N
0°N
10°S
20°S
30°S
40°S
50°S
60°S
70°S
80°S
80°N
70°N
60°N
50°N
40°N
30°N
20°N
10°N
0°N
10°S
20°S
30°S
40°S
50°S
60°S
70°S
80°S
340°E320°E300°E280°E260°E240°E220°E200°E180°E160°E140°E120°E100°E80°E60°E40°E20°E
340°E320°E300°E280°E260°E240°E220°E200°E180°E160°E140°E120°E100°E80°E60°E40°E20°E
< 10% 10.. 20 20.. 30 30.. 40 40.. 50 50.. 60 60.. 70 70.. 80 80.. 90 > 90%
Probability of a TS passing within 300km radiusWeekly mean Tropical Storm Strike Probability. Date: 20101122 0 UTC t+(432-600)
80°N
70°N
60°N
50°N
40°N
30°N
20°N
10°N
0°N
10°S
20°S
30°S
40°S
50°S
60°S
70°S
80°S
80°N
70°N
60°N
50°N
40°N
30°N
20°N
10°N
0°N
10°S
20°S
30°S
40°S
50°S
60°S
70°S
80°S
340°E320°E300°E280°E260°E240°E220°E200°E180°E160°E140°E120°E100°E80°E60°E40°E20°E
340°E320°E300°E280°E260°E240°E220°E200°E180°E160°E140°E120°E100°E80°E60°E40°E20°E
< 10% 10.. 20 20.. 30 30.. 40 40.. 50 50.. 60 60.. 70 70.. 80 80.. 90 > 90%
Probability of a TS passing within 300km radiusWeekly mean Tropical Storm Strike Probability. Date: 20101122 0 UTC t+(600-768)
ROC AREA over SH
Day 5-11 Day 12-18
Day 19-25 Day 26-32
80°N
70°N
60°N
50°N
40°N
30°N
20°N
10°N
0°N
10°S
20°S
30°S
40°S
50°S
60°S
70°S
80°S
80°N
70°N
60°N
50°N
40°N
30°N
20°N
10°N
0°N
10°S
20°S
30°S
40°S
50°S
60°S
70°S
80°S
340°E320°E300°E280°E260°E240°E220°E200°E180°E160°E140°E120°E100°E80°E60°E40°E20°E
340°E320°E300°E280°E260°E240°E220°E200°E180°E160°E140°E120°E100°E80°E60°E40°E20°E
< 10% 10.. 20 20.. 30 30.. 40 40.. 50 50.. 60 60.. 70 70.. 80 80.. 90 > 90%
Probability of a TS passing within 300km radiusWeekly mean Tropical Storm Strike Probability. Date: 20101122 0 UTC t+( 96-264)
Exeter 1-3 December 2010
Impact of ocean-atmosphere coupling
Figure 4: Correlation of the observed RMM1 and RMM2 timeseries with the ensemblemean forecast timeseries, based on 47 start dates, for the control experiment, CONT(solid line), the mixed layer experiment, ML (dashed line) and the persisted SST ex-periment, PERS (dotted line).
26
Woolnough et al, QJRMS, 2007
Per. SST anomalies
ML
OGCM
Exeter 1-3 December 2010
Soil Moisture Initial Conditions
Exeter 1-3 December 2010 23
GLACE2 Series 1 – Series 2 – ECMWF AMIP
DAY 0-15 DAY 16-30 DAY 31-45
Courtesy Bart van den Hurk
Exeter 1-3 December 2010
Stratospheric initial conditions
Exeter 1-3 December 2010
Stratospheric Sudden Warmings
Impact of vertical resolution
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
Day
-30
-25
-20
-15
-10
-5
0
5
10
15
20
25
30T
50 G
radi
ent
L91 Mean L91 L62 Mean L62 Ana..
0 5 10 15 20 25 300
2
4
6
8
10
Spread L91
RMS error L91RMS error L62
Spread L62
Forecast starting on
5/1/06
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
Day
-30
-25
-20
-15
-10
-5
0
5
10
15
20
25
30
T50 G
radie
nt
L91 Mean L91 L62 Mean L62 Ana.
Forecast starting on
19/1/06
L91 L62
Exeter 1-3 December 2010
Impact of Better stratospheric vertical resolution
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1false alarm rate
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
hit
rate
week2 19961115-20071115ECMWF Monthly Forecast, Z500 upper tercile , Area:Northern Extratropics
ROC score = 0.737ROC score = 0.734
0 0.2 0.4 0.6 0.8 1rel FC distribution
41858370
0.126 105
0.167 105
0.209 105
f9np
f71f
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1false alarm rate
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
hit r
ate
week3 19961115-20071115ECMWF Monthly Forecast, Z500 upper tercile , Area:Northern Extratropics
ROC score = 0.600ROC score = 0.605
0 0.2 0.4 0.6 0.8 1rel FC distribution
40108020
0.120 105
0.160 105
0.201 105
f9np
f71f
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1false alarm rate
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
hit r
ate
week4 19961115-20071115ECMWF Monthly Forecast, 2mtm upper tercile , Area:Northern Extratropics
ROC score = 0.578ROC score = 0.586
0 0.2 0.4 0.6 0.8 1rel FC distribution
43508700
0.131 105
0.174 105
0.218 105
f9np
f71f
Day 12-18 Day 19-25 Day 26-32
62 levels 91 levels
Probability that Z500 anomalies are in upper tercile1st Feb/May/Aug/Oct 1989-2008 (80 cases)
Exeter 1-3 December 2010
Stratospheric Sudden Warmings
Impact of S-Svs
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
Day
-30
-25
-20
-15
-10
-5
0
5
10
15
20
25
30
T50
Gra
dien
t
S-SVs Mean S-SVs L62 Mean L62 Ana.
Forecast 5/01/06
Forecast26/01/06
Ensemble spread
Control S-Svs
5 10 15 20 25 30Time in days
0
1
2
3
4
5
6
Sp
rea
d
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
Day
-30
-25
-20
-15
-10
-5
0
5
10
15
20
25
30
T50
Gra
dien
t
S-SVs Mean S-SVs L62 Mean L62 Ana.
Work with J. Barkmeijer, T. Jung and M. Leutbecher
Exeter 1-3 December 2010
46-day EPS experimentComparison with System 3
Exeter 1-3 December 2010
Global Scores
2MTM- Ensemble mean correlation with analysis
August 1981-2007
June 2MTM
80°S80°S
70°S 70°S
60°S60°S
50°S 50°S
40°S40°S
30°S 30°S
20°S20°S
10°S 10°S
0°0°
10°N 10°N
20°N20°N
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
70°N 70°N
80°N80°N
160°W
160°W 140°W
140°W 120°W
120°W 100°W
100°W 80°W
80°W 60°W
60°W 40°W
40°W 20°W
20°W 0°
0° 20°E
20°E 40°E
40°E 60°E
60°E 80°E
80°E 100°E
100°E 120°E
120°E 140°E
140°E 160°E
160°E
<0.2 0.2..0.3 0.3..0.4 0.4..0.5 0.5..0.6 0.6..0.7 0.7..0.8 0.8..0.9 0.9..0.95 > 0.95
June 2MTM
80°S80°S
70°S 70°S
60°S60°S
50°S 50°S
40°S40°S
30°S 30°S
20°S20°S
10°S 10°S
0°0°
10°N 10°N
20°N20°N
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
70°N 70°N
80°N80°N
160°W
160°W 140°W
140°W 120°W
120°W 100°W
100°W 80°W
80°W 60°W
60°W 40°W
40°W 20°W
20°W 0°
0° 20°E
20°E 40°E
40°E 60°E
60°E 80°E
80°E 100°E
100°E 120°E
120°E 140°E
140°E 160°E
160°E
<0.2 0.2..0.3 0.3..0.4 0.4..0.5 0.5..0.6 0.6..0.7 0.7..0.8 0.8..0.9 0.9..0.95 > 0.95
SEAS- Month 2 VEPS
Exeter 1-3 December 2010
EPS Day 16-45
46-day EPS extension – DJFM – N. extra.
Seas3 EPS
TropicsNorthern Extratropics
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1forecast probability
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
obs
freq
uenc
y
6113
6504
6773
6329
5506
4652
3633
2895 2133
1616
1888
4841
59767085
7042
6642
52133832
2882 2061
1240
1228
week1 19951215-20061215ECMWF Monthly Forecast, 2MTM upper tercile , Area:Extratropics
BrSc = 0.233 LCBrSkSc= -0.02 Uncertainty= 0.228BrSc = 0.243 LCBrSkSc= -0.06 Uncertainty= 0.228
0 0.2 0.4 0.6 0.8 1rel FC distribution
0
0.2
0.4
0.6
0.8
1
B(S)S_REL= 0.026 ( 0.89)B(S)S_RSL= 0.014 ( 0.06)
sample clim
clim 1990-2001
ex2j ez90
ROC Diagram Reliability Diagram
Seas Month 2
Exeter 1-3 December 2010
Interannual variability of June rainfall over India
1989-2007
Correlation RMS ERROR
VAREPS- 15 May
Seas - Month 2
Seas – Month 1
0.62
0.40
0.52
0.90
1.15
0.96
Verification: 1ox1o gridded daily rainfall data from IMD
Exeter 1-3 December 2010
Interannual variability of Atlantic hurricanes
1981-2007
August September October
VAREPS- 15th
Seas - Month 1
Seas – Month 2
0.77
0.31
-0.03
0.37
0.33
0.23
0.69
0.18
0.18
Correlation with HURDAT
Exeter 1-3 December 2010
Conclusion
• Forecasts for days 12-18 that are generally better than climatology and
persistence of day 5-11. Beyond 20 days the monthly forecast is
marginally skilful.
• The MJO is the main source of predictability in the northern Extratropics
for weeks 3 and 4.
• Extending EPS forecasts can help to produce more frequent and skilful
short-range seasonal forecasts, particularly for some extreme events.
Exeter 1-3 December 2010
Future Plans
• Run the monthly forecasts twice a week
• Ocean/atmosphere Coupling from day 0
• Extend forecast range to 46-60 days
Exeter 1-3 December 2010
Multi-model combination
ECMWF NCEP (MRF) ECMWF+NCEP
Extreme tercile probability forecast. Northern Hemisphere. DJF. 84 cases (1990-2002)
T850
Whitaker et al, 2005
Exeter 1-3 December 2010
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
ensemble size = 51 ,climate size = 60Forecast start reference is 25-07-20032-meter Temperature anomalyECMWF Monthly Forecasting System
Solid contour at 95% significanceShaded areas above 90% significance
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
DAY 5-11: 29-07-2003/TO/04-08-2003 DAY 12-18 :05-08-2003/TO/11-08-2003
DAY 19-25 :12-08-2003/TO/18-08-2003 DAY 26-32:19-08-2003/TO/25-08-2003
< -6deg -6.. -4 -4.. -2 -2.. -1 -1.. 0 0.. 1 1.. 2 2.. 4 4.. 6 > 6deg
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
ensemble size = 15 ,climate size = 60Forecast start reference is 23-07-20032-meter Temperature anomalyECMWF Monthly Forecasting System
Solid contour at 95% significanceShaded areas above 90% significance
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
DAY 5-11: 27-07-2003/TO/02-08-2003 DAY 12-18 :03-08-2003/TO/09-08-2003
DAY 19-25 :10-08-2003/TO/16-08-2003 DAY 26-32:17-08-2003/TO/23-08-2003
< -6deg -6.. -4 -4.. -2 -2.. -1 -1.. 0 0.. 1 1.. 2 2.. 4 4.. 6 > 6deg
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
Climatology: 1995-2006Reference date is 30-07-20032-meter temperature anomalyAnalysis WEEK1-4
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
WEEK1: 03-08-2003/TO/09-08-2003 WEEK2 :10-08-2003/TO/16-08-2003
WEEK3 :17-08-2003/TO/23-08-2003 WEEK4 :24-08-2003/TO/30-08-2003
< -6deg -6.. -4 -4.. -2 -2.. -1 -1.. 0 0.. 1 1.. 2 2.. 4 4.. 6 > 6deg
MAGICS 6.11 bee10 - nec Fri Apr 27 15:14:30 2007 * 4 ERROR(S) FOUND *
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
ensemble size = 15 ,climate size = 60Forecast start reference is 25-07-20032-meter Temperature anomalyECMWF Monthly Forecasting System
Solid contour at 95% significanceShaded areas above 90% significance
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
DAY 5-11: 29-07-2003/TO/04-08-2003 DAY 12-18 :05-08-2003/TO/11-08-2003
DAY 19-25 :12-08-2003/TO/18-08-2003 DAY 26-32:19-08-2003/TO/25-08-2003
< -6deg -6.. -4 -4.. -2 -2.. -1 -1.. 0 0.. 1 1.. 2 2.. 4 4.. 6 > 6deg
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
Climatology: 1995-2006Reference date is 30-07-20032-meter temperature anomalyAnalysis WEEK1-4
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
WEEK1: 03-08-2003/TO/09-08-2003 WEEK2 :10-08-2003/TO/16-08-2003
WEEK3 :17-08-2003/TO/23-08-2003 WEEK4 :24-08-2003/TO/30-08-2003
< -6deg -6.. -4 -4.. -2 -2.. -1 -1.. 0 0.. 1 1.. 2 2.. 4 4.. 6 > 6deg
MAGICS 6.11 bee10 - nec Fri Apr 27 15:14:30 2007 * 4 ERROR(S) FOUND *
a) Analysis b) Operational MOFC
c) MOFC CY31R2 d) VAREPS CY31R2
Forecasts started on 23 July 2003 for 2mT anomalies for 3-9 August 2003 (fc day 12-18): impact of model cycle and upgrade to 32-day VAREPS.
Test case : Summer 2003 Heat Wave
Exeter 1-3 December 2010
The ECMWF VarEPS-monthly forecasting system
• A 51-member ensemble is integrated for 32 days every week
• Atmospheric component: IFS with the latest operational cycle and with a T639L62 resolution till day 10 and T319L62 after day 10.
• Persisted SST anomalies till day 10 and ocean-atmosphere coupling from day 10 till day 32.
• Oceanic component: HOPE (from Max Plank Institute) with a zonal resolution of 1.4 degrees and 29 vertical levels
• Coupling: OASIS (CERFACS). Coupling every 3 hours.
Exeter 1-3 December 2010
Stratospheric Sudden warming- January 2009
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
Day
-30
-25
-20
-15
-10
-5
0
5
10
15
20
25
30
T50
Gra
dien
t
Mem. Ctr Mean Ana.
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
Day
-30
-25
-20
-15
-10
-5
0
5
10
15
20
25
30
T50
Gra
dien
t
Mem. Ctr Mean Ana.
8/1/2009 15/1/2009SSW Index (T50 gradient)
Exeter 1-3 December 2010
Stratospheric Sudden warming- January 2009
15/1/2009 2mtm anomaly Forecast
AnalysisComposite Good SW
Composite Bad SW
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
30 30
4040
50 50
6060
20
20 0
0 20
20
Contours at 1% levelShaded areas significant at 10% levelensemble size = 51 ,climate size = 90
Verification period: 02-02-2009/TO/08-02-20092-meter Temperature anomaly
Analysis and ECMWF VarEPS-Monthly Forecasting System
30 30
4040
50 50
6060
20
20 0
0 20
20
30 30
4040
50 50
6060
20
20 0
0 20
20
30 30
4040
50 50
6060
20
20 0
0 20
20
ANALYSIS
FORECAST 29-01-2009: DAY 5-11 FORECAST 22-01-2009: DAY 12-18
FORECAST 15-01-2009: DAY 19-25 FORECAST 08-01-2009: DAY 26-32
<-10deg
-10.. -6
-6.. -3
-3.. -1
-1.. 0
0.. 1
1.. 3
3.. 6
6.. 10
> 10deg
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
30 30
4040
50 50
6060
20
20 0
0 20
20
Contours at 1% levelShaded areas significant at 10% levelensemble size = 51 ,climate size = 90
Verification period: 09-02-2009/TO/15-02-20092-meter Temperature anomaly
Analysis and ECMWF VarEPS-Monthly Forecasting System
30 30
4040
50 50
6060
20
20 0
0 20
20
30 30
4040
50 50
6060
20
20 0
0 20
20
30 30
4040
50 50
6060
20
20 0
0 20
20
ANALYSIS
FORECAST 05-02-2009: DAY 5-11 FORECAST 29-01-2009: DAY 12-18
FORECAST 22-01-2009: DAY 19-25 FORECAST 15-01-2009: DAY 26-32
<-10deg
-10.. -6
-6.. -3
-3.. -1
-1.. 0
0.. 1
1.. 3
3.. 6
6.. 10
> 10deg
Day 19-25
Day 26-32
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
ensemble size = 51 ,climate size = 90Forecast start reference is 15-01-20092-meter Temperature anomalyECMWF VAREPS-Monthly Forecasting System
Contours at 1% levelShaded areas significant at 10% levelREFDATE1=02-02-2009/TO/08-02-2
Day 19-25
<-10deg -10.. -6 -6.. -3 -3.. -1 -1.. 0 0.. 1 1.. 3 3.. 6 6.. 10 > 10deg
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
ensemble size = 51 ,climate size = 90Forecast start reference is 15-01-20092-meter Temperature anomalyECMWF VAREPS-Monthly Forecasting System
Contours at 1% levelShaded areas significant at 10% levelREFDATE1=02-02-2009/TO/08-02-2
Day 19-25
<-10deg -10.. -6 -6.. -3 -3.. -1 -1.. 0 0.. 1 1.. 3 3.. 6 6.. 10 > 10deg
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
ensemble size = 51 ,climate size = 90Forecast start reference is 15-01-20092-meter Temperature anomalyECMWF VAREPS-Monthly Forecasting System
Contours at 1% levelShaded areas significant at 10% levelREFDATE1=02-02-2009/TO/08-02-2
Day 19-25
<-10deg -10.. -6 -6.. -3 -3.. -1 -1.. 0 0.. 1 1.. 3 3.. 6 6.. 10 > 10deg
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
ensemble size = 51 ,climate size = 90Forecast start reference is 15-01-20092-meter Temperature anomalyECMWF VAREPS-Monthly Forecasting System
Contours at 1% levelShaded areas significant at 10% levelREFDATE1=02-02-2009/TO/08-02-2
Day 19-25
<-10deg -10.. -6 -6.. -3 -3.. -1 -1.. 0 0.. 1 1.. 3 3.. 6 6.. 10 > 10deg
30°N 30°N
40°N40°N
50°N 50°N
60°N60°N
20°W
20°W 0°
0° 20°E
20°E
30 30
4040
50 50
6060
20
20 0
0 20
20
Contours at 1% levelShaded areas significant at 10% levelensemble size = 51 ,climate size = 90
Verification period: 02-02-2009/TO/08-02-20092-meter Temperature anomaly
Analysis and ECMWF VarEPS-Monthly Forecasting System
30 30
4040
50 50
6060
20
20 0
0 20
20
30 30
4040
50 50
6060
20
20 0
0 20
20
30 30
4040
50 50
6060
20
20 0
0 20
20
ANALYSIS
FORECAST 29-01-2009: DAY 5-11 FORECAST 22-01-2009: DAY 12-18
FORECAST 15-01-2009: DAY 19-25 FORECAST 08-01-2009: DAY 26-32
<-10deg
-10.. -6
-6.. -3
-3.. -1
-1.. 0
0.. 1
1.. 3
3.. 6
6.. 10
> 10deg
Exeter 1-3 December 2010
MJO Propagation
1 2 3 4 5 6 7 8
MJO PHASE
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
DA
YS
MJO (%)
< 5% 5.. 10 10.. 15 15.. 20 20.. 25 25.. 30 30.. 40 40.. 60 60.. 80 > 80%
1 2 3 4 5 6 7 8
MJO PHASE
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
DA
YS
MJO (%)
< 5% 5.. 10 10.. 15 15.. 20 20.. 25 25.. 30 30.. 40 40.. 60 60.. 80 > 80%
ForecastAnalysis
Exeter 1-3 December 2010
Convection changes to operational massflux scheme (CY32R3)
New formulation of convective entrainment:
Previously linked to moisture convergence
– Now more dependent on the relative dryness of the environment
New formulation of relaxation timescale used in massflux closure:
Previously only varied with horizontal resolution – Now a variable that is dependent on the convective turnover timescale i.e. variable in both space and time also
Impact of these changes is large including a major increase in tropical variability
Bechtold et al, QJRMS, 2008