15-day VAREPS and monthly forecasting · • South Indian Ocean: Bessafi and Wheeler (2006); Ho et...

High Resolution Modeling Workshop- Trieste 10-14 August 2009

Impact of the MJO on tropical storms in the ECMWF EPS

Frédéric Vitart

European Centre for Medium-Range Weather Forecasts


Outline

1. Improvements in the simulation of MJO and TCs at ECMWF

2. Hindcast Experiment

3. Impact of the MJO on model tropical storms

3. Conclusion


Observational studies

• Western North Pacific:

Nakazawa (1988); Liebmann et al (1994)

• Eastern North Pacific:

Molinari et al, (1997); Maloney and Hartmann (2000)

• Gulf of Mexico:

Maloney and Hartmann (2000); Mo (2002)

• South Indian Ocean:

Bessafi and Wheeler (2006); Ho et al (2006)

• Australian region:

Hall et al (2001)

• Impact on tropical cyclone genesis index: Camargo et al (2009)


PHASE AMPLITUDEVelocity potential

MJO Prediction


OLR- 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

-10

-10

-10

-10-1

0

-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 mean

ewku

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 1/0231/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 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 mean

ex6i

-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

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

-10-1

0

-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 mean

ewku

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 1/0231/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 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 mean

ex6i

-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

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

-10-1

0

-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 mean

ewku

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 mean

ex6i

-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

ERA40

10

-10

-10

-10

-10

-10-1

0

-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 mean

elz5

-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 mean

ek7h

-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

-10

-10

-10

-10

-10-1

0

-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 mean

elz5

-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 mean

ek7h

-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

-10

-10

-10

-10

-10-1

0

-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 mean

es8c

-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 mean

er98

-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

-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 mean

f4i5-1

0

-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 mean

f1xi

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

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 mean

f4i5

-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 mean

f1xi

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

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 1/0231/0130/0129/0128/0127/0126/0125/0124/0123/0122/0121/0120/0119/0118/0117/0116/0115/0114/0113/0112/0111/0110/01 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 mean

f46n

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 mean

f6ju

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

33R1 35R1 35R3

06/08 09/08 09/09


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


Tropical Cyclone Tracking (Vitart 1997, 2003)

Step 1: Detection of intense vortices with a warm core for each time step:

• A local maximum of 850 hPa vorticity is located

• The closest minimum of sea level pressure is defined as the centre of the storm

• Detection of a warm core above the centre of the storms

Step 2: Connect the vortices into tracks:

• The steering wind is used to compute a first guess.

• maximum wind velocity at 10m should exceed 17 m/s. Criteria are resolution dependent.


Tropical storm climatology: 1978-2007- ASO

HURDAT CY32R3 CY30R1 (SYS3)

TS genesis

10°N10°N

20°N 20°N

30°N30°N

40°N 40°N

50°N50°N

60°N 60°N

70°N70°N

100°W

100°W 80°W

80°W 60°W

60°W 40°W

40°W 20°W

20°W 0°

0°

< 1 1.. 2 2.. 3 3.. 4 4.. 5 5.. 6 6.. 7 7.. 8 8.. 9 > 9

TS density

10°N10°N

20°N 20°N

30°N30°N

40°N 40°N

50°N50°N

60°N 60°N

70°N70°N

100°W

100°W 80°W

80°W 60°W

60°W 40°W

40°W 20°W

20°W 0°

0°

< 1 1.. 2 2.. 3 3.. 4 4.. 5 5.. 6 6.. 7 7.. 8 8.. 9 > 9

TS density

10°N10°N

20°N 20°N

30°N30°N

40°N 40°N

50°N50°N

60°N 60°N

70°N70°N

100°W

100°W 80°W

80°W 60°W

60°W 40°W

40°W 20°W

20°W 0°

0°

< 1 1.. 2 2.. 3 3.. 4 4.. 5 5.. 6 6.. 7 7.. 8 8.. 9 > 9

Number of tropical storm last day within 2 degrees

Number of tropical storm days within 2 degrees

TS density

10°N10°N

20°N 20°N

30°N30°N

40°N 40°N

50°N50°N

60°N 60°N

70°N70°N

100°W

100°W 80°W

80°W 60°W

60°W 40°W

40°W 20°W

20°W 0°

0°

< 2 2.. 4 4.. 6 6.. 8 8.. 10 10.. 12 12.. 16 16.. 18 18.. 20 > 20

TS density

10°N10°N

20°N 20°N

30°N30°N

40°N 40°N

50°N50°N

60°N 60°N

70°N70°N

100°W

100°W 80°W

80°W 60°W

60°W 40°W

40°W 20°W

20°W 0°

0°

< 2 2.. 3 3.. 4 4.. 8 8.. 10 10.. 12 12.. 16 16.. 18 18.. 20 > 20

TS density

10°N10°N

20°N 20°N

30°N30°N

40°N 40°N

50°N50°N

60°N 60°N

70°N70°N

100°W

100°W 80°W

80°W 60°W

60°W 40°W

40°W 20°W

20°W 0°

0°

< 2 2.. 4 4.. 6 6.. 8 8.. 10 10.. 12 12.. 16 16.. 20 20.. 24 > 24


HURDAT EPS

AUG.

SEPT.

OCT.

TS density

10°N10°N

20°N 20°N

30°N30°N

40°N 40°N

50°N50°N

60°N 60°N

70°N70°N

100°W

100°W 80°W

80°W 60°W

60°W 40°W

40°W 20°W

20°W 0°

0°

< 2 2.. 4 4.. 6 6.. 8 8.. 10 10.. 12 12.. 16 16.. 18 18.. 20 > 20

TS density

10°N10°N

20°N 20°N

30°N30°N

40°N 40°N

50°N50°N

60°N 60°N

70°N70°N

100°W

100°W 80°W

80°W 60°W

60°W 40°W

40°W 20°W

20°W 0°

0°

< 2 2.. 4 4.. 6 6.. 8 8.. 10 10.. 12 12.. 16 16.. 18 18.. 20 > 20

TS density

10°N10°N

20°N 20°N

30°N30°N

40°N 40°N

50°N50°N

60°N 60°N

70°N70°N

100°W

100°W 80°W

80°W 60°W

60°W 40°W

40°W 20°W

20°W 0°

0°

< 2 2.. 4 4.. 6 6.. 8 8.. 10 10.. 12 12.. 16 16.. 18 18.. 20 > 20

TS density

10°N10°N

20°N 20°N

30°N30°N

40°N 40°N

50°N50°N

60°N 60°N

70°N70°N

100°W

100°W 80°W

80°W 60°W

60°W 40°W

40°W 20°W

20°W 0°

0°

< 2 2.. 4 4.. 6 6.. 8 8.. 10 10.. 12 12.. 16 16.. 18 18.. 20 > 20

TS density

10°N10°N

20°N 20°N

30°N30°N

40°N 40°N

50°N50°N

60°N 60°N

70°N70°N

100°W

100°W 80°W

80°W 60°W

60°W 40°W

40°W 20°W

20°W 0°

0°

< 2 2.. 4 4.. 6 6.. 8 8.. 10 10.. 12 12.. 16 16.. 18 18.. 20 > 20

TS density

10°N10°N

20°N 20°N

30°N30°N

40°N 40°N

50°N50°N

60°N 60°N

70°N70°N

100°W

100°W 80°W

80°W 60°W

60°W 40°W

40°W 20°W

20°W 0°

0°

< 2 2.. 4 4.. 6 6.. 8 8.. 10 10.. 12 12.. 16 16.. 18 18.. 20 > 20

Number of tropical storm days within 2 degrees


Forecast Biases Precipitation for DJF against GPCP for different cycles: from 15 year 5

months integrations for 1990-2005.

CY31R1 Sep 2006

CY32R3 Nov 2007CY32R2 June 2007


Hindcast Experiment

• 15-member ensemble forecasts starting on the 15th of each

month from 1989 to 2008.

• 46-day integrations

• Cycle 32R3

• T399 (50 km) uncoupled till day 10 and T255 (80km)

coupled after day 10


Ocean only integration

Coupled forecast at TL255 (80 km)

Day 46

Atmosphere-only Integration at T399 (50 km)

Initial condition

Heat flux, Wind stress, P-E

Day 10

Experimental setup


46-day hindcast experiment

• Atmospheric initial conditions: ERA40 + ECMWF

operational analysis

• Oceanic initial conditions: ECMWF Ocean Reanalysis

• Perturbations:

Atmosphere: Singular vectors + stochastic physics

Ocean: wind stress perturbations during data assimilation.


MJO Diagnostics

Combined EOF1

Combined EOF2

From Wheeler and Hendon, BMRC


MJO FORECAST

-4 -3 -2 -1 0 1 2 3 4

RMM1

-4

-3

-2

-1

0

1

2

3

4

RM

M2

FORECAST BASED 15/05/1997 00UTC

ECMWF MONTHLY FORECASTS

and Africa

West Hem.

Continent

Maritime

Pacific

Western

Ocean

Indian

2

1

8

7 6

5

4

3

Day 1 Day 5 Day 10

Day 15 Day 20 Analysis

Ens. Mean Verification


Amplitude of the MJO

Mean of the

ensembleIndividual ensemble members

Mean standard deviation of PC1 and PC2

0 5 10 15 20 25 30 35 40 45

Time range (Days)

0.8

0.9

1

1.1

1.2

1.3

1.4

1.5

1.6

Am

plit

ud

e o

f th

e M

JO


MJO Propagation

-4 -3 -2 -1 0 1 2 3 4

RMM1

-4

-3

-2

-1

0

1

2

3

4

RM

M2


ECMWF MONTHLY FORECASTS

and Africa

West Hem.

Continent

Maritime

Pacific

Western

Ocean

Indian

2

1

8

7 6

5

4

3

Day 1 Day 5 Day 10

Day 15 Day 20 Analysis

Ens. Mean Verification


Skill to predict MJO

PC1 PC2

Correlation with analysis (ERA Interim)


NDJFMAObservations Model

JASON

TS GENESIS

30°S30°S

20°S 20°S

10°S10°S

0° 0°

10°N10°N

20°N 20°N

30°N30°N

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 180°

180° 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

< 10 10.. 15 15.. 20 20.. 25 25.. 30 30.. 35 35.. 40 40.. 45 45.. 50 > 50

TS GENESIS

30°S30°S

20°S 20°S

10°S10°S

0° 0°

10°N10°N

20°N 20°N

30°N30°N

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 180°

180° 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

< 10 10.. 15 15.. 20 20.. 25 25.. 30 30.. 35 35.. 40 40.. 45 45.. 50 > 50

TS GENESIS

30°S30°S

20°S 20°S

10°S10°S

0° 0°

10°N10°N

20°N 20°N

30°N30°N

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 180°

180° 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

< 10 10.. 15 15.. 20 20.. 25 25.. 30 30.. 35 35.. 40 40.. 45 45.. 50 > 50

TS GENESIS

30°S30°S

20°S 20°S

10°S10°S

0° 0°

10°N10°N

20°N 20°N

30°N30°N

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 180°

180° 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

< 10 10.. 15 15.. 20 20.. 25 25.. 30 30.. 35 35.. 40 40.. 45 45.. 50 > 50

Tropical Cyclone Genesis climatology

1989-2008


Tropical Cyclone Density climatology

1989-2008


MJO Composites of VP200 hPa

ECMWF Analysis VT:Friday 15 November 1991 00UTC 200hPa Velocity potential

20

30

40

50

60

68.93

-100

-90

-80

-70

-60

-50

-40

-30

-20

Phase 1 ECMWF Analysis VT:Friday 15 November 1991 00UTC 200hPa Velocity potential

-100

-90

-80

-70

-60

-50

-40

-30

-20

20

30

40

50

56.35


-100

-90

-80

-70

-60

-50

-40

-30

-20

20

30

37.92


20

30

40

46.83

-100

-90

-80

-70

-60

-50

-40

-30

-20

Phase 3 Phase 4


-100

-90

-80

-70

-60

-50

-40

-30

-20

20

30

40

50

59.09


20

30

40

50

60

70

76.80

-100

-90

-80

-70

-60

-50

-40

-30

-20


20

30

40

50

60

70

74.74

-100

-90

-80

-70

-60

-50

-40

-30

-20

Phase 7 Phase 8 ECMWF Analysis VT:Friday 15 November 1991 00UTC 200hPa Velocity potential

-100

-90

-80

-70

-60

-50

-40

-30

-20

Phase 5


MJO Composite- NDJFMA

Tropical storm density anomaly

Vitart, 2009, GRL


MJO Composite- ASO

Tropical storm density anomaly

Vitart, 2009, GRL


Australia

NDJFMA

South+East US

Coast

ASO

West Coast

US+Mexico

ASO

Phase 2+3 -50%

(-30%)

+45%

(+73%)

+43%

(+100%)

Phase 4+5 +50%

(+96%)

-16%

(-56%)

-22%

(-68%)

Phase 6+7 +71%

(+25%)

-30%

(-71%)

-37%

(-83%)

Phase 8+1 -22%

(-70%)

+9%

(+80%)

+39%

(+100%)

Landfall Activity

Vitart, GRL, 2009


Product

ECMWF:

Weather and Climate

Dynamical Forecasts

Medium-Range

Forecasts

Day 1-10(15)

Monthly

Forecast

Day 10-32

Seasonal

Forecasts

Month 2-7

Forecasting systems at ECMWF


The seamless EPS/monthly ensemble system

On the 11th of Mar ‘08 the 15-day variable resolution EPS (VAREPS) was merged with the monthly ensemble system; since then the 00 UTC forecasts use a coupled ocean model from day 10.

Jan ’06: 00 & 12 Z

Feb ’06: 00 & 12 Z

Sep ’06: 00 & 12 Z

TL255L40

TL399L62

TL255L62TL399L62

TL399L62 TL255L62 TL255L62

T=0 10 d 32 d15 d

TL255L62TL399L62Mar ’08: 12 Z

00 Z

(TL399 ~ 50 km in grid point space, TL255 ~ 80 km)


Seamless prediction of tropical storms

Forecast Products Users Meeting 10-12 June 2009

Slide 30

Tropical cyclone Aila (24-25 May 2009)

Str ike Probability (%)

10°N10°N

20°N 20°N

30°N30°N

40°N 40°N

60°E

60°E 80° E

80° E

5.. 10 10.. 2 0 20.. 3 0 30.. 40 40.. 50 50.. 6 0 60.. 70 70.. 8 0 80.. 9 0 > 90%

Str ike Probability (%)

10°N10°N

20°N 20°N

30°N30°N

40°N 40°N

60°E

60°E 80° E

80° E

5.. 10 10.. 2 0 20.. 3 0 30.. 40 40.. 50 50.. 6 0 60.. 70 70.. 8 0 80.. 9 0 > 90%

90 °E80° E70° E60°E50° E

90 °E80° E70° E60°E50° E

40° N

30° N

20° N

10° N

40°N

30° N

20°N

10° N

5.. 10 10.. 20 20.. 30 30.. 40 40.. 50 50.. 60 60.. 70 70.. 80 80.. 90 > 90%

y p g

EPS from 7 May: days 19-25

(25 - 31 May)

EPS from 14 May: days 12-18

(25 - 31 May)

EPS from 20 May: h 96-144

(24 - 26 May)

Tropical cyclone Aila observed

24-25 May 2009


Monthly prediction Of TC activity

30

25

20

15

10

5

0

-5

-10

-15

-20

-25

-30

DA

YS

30E 90E 150E 150W 90W 30W

LONGITUDE

30E 90E 150E 150W 90W 30W


ENSEMBLE MEAN BETWEEN LAT 15S AND 15N

Velocity potential anomaly at 200 hPa

HOVMOLLER DIAGRAM OF MONTHLY FORECAST

2

22

2

2

2

2

2

2

6

6

6

6

6

10

10

14

-10

-6-6

-2

-2

-2

-2

-2

-2

-2

-2

-2

-2

-2

8/06

6/06

4/06

2/06

31/05

29/05

27/05

25/05

23/05

21/05

19/05

17/05

15/05

13/05

11/05

9/05

7/05

5/05

3/05

1/05

29/04

27/04

25/04

23/04

21/04

19/04

17/04

15/04

13/04

11/04

9/04

7/04

5/04

FO

RE

CA

ST

A

NA

LY

SIS

30

25

20

15

10

5

0

-5

-10

-15

-20

-25

-30

DA

YS

30E 90E 150E 150W 90W 30W

LONGITUDE

30E 90E 150E 150W 90W 30W


ENSEMBLE MEAN BETWEEN LAT 15S AND 15N

Velocity potential anomaly at 200 hPa

HOVMOLLER DIAGRAM OF MONTHLY FORECAST

2

2

2

2

2

2

2

2

2

2

2

2

2

2

6

6

6

6

10

14

-10

-6

-6

-6

-6

-2

-2-2

-2

-2

-2

-2 -2

-2

-2

-2

-2

-2

-2

8/06

6/06

4/06

2/06

31/05

29/05

27/05

25/05

23/05

21/05

19/05

17/05

15/05

13/05

11/05

9/05

7/05

5/05

3/05

1/05

29/04

27/04

25/04

23/04

21/04

19/04

17/04

15/04

13/04

11/04

9/04

7/04

5/04

FO

RE

CA

ST

A

NA

LY

SIS

VP200 Anomaly


Monthly forecasts of tropical storms- 20090806

Day 5-11 Day 12-18

Day 19-25 Day 26-32

340°E320°E300°E280°E260°E240°E220°E200°E180°E160°E140°E120°E100°E80°E60°E40°E20°E


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

< 10% 10.. 20 20.. 30 30.. 40 40.. 50 50.. 60 60.. 70 70.. 80 80.. 90 > 90%

Probability of a TS passing within 500km radius

Weekly mean Tropical Storm Strike Probability. Date: 20090806 0 UTC t+(264-408)



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

< 10% 10.. 20 20.. 30 30.. 40 40.. 50 50.. 60 60.. 70 70.. 80 80.. 90 > 90%


Weekly mean Tropical Storm Strike Probability. Date: 20090806 0 UTC t+( 96-240)



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

< 10% 10.. 20 20.. 30 30.. 40 40.. 50 50.. 60 60.. 70 70.. 80 80.. 90 > 90%





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

< 10% 10.. 20 20.. 30 30.. 40 40.. 50 50.. 60 60.. 70 70.. 80 80.. 90 > 90%




Conclusion

• MJO and Tropical Cyclone activity are more realistic since

32R3

• The MJO suffers from a too slow propagation and has

difficulties to cross the Maritime Continent.

• The model simulates a realistic impact of the MJO on

model tropical storms, although the impact tends to be

weaker than observed

• First step towards seamless prediction of tropical storms:

merging of the EPS and monthly forecasting systems.

15-day VAREPS and monthly forecasting · • South Indian Ocean: Bessafi and Wheeler (2006); Ho et...

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Transcript of 15-day VAREPS and monthly forecasting · • South Indian Ocean: Bessafi and Wheeler (2006); Ho et...