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27

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EQ.

30N

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2525

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30S

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25

25

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30S

EQ.

30N

25

25

11

25

g. December (OBS)

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30S

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30N

25

27

25

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90W 45W 0 45E

30S

EQ.

30N

31

25

d. June (CTL)

90W 45W 0 45E

30S

EQ.

30N

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21

29

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90W 45W 0 45E

30S

EQ.

30N

19

7

2525

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30S

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30N

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90W 45W 0 45E

30S

EQ.

30N

8 5

2

c. June (OBS)

90W 45W 0 45E

30S

EQ.

30N

5 2

e. September (OBS)

90W 45W 0 45E

30S

EQ.

30N

8

52

g. December (OBS)

90W 45W 0 45E

30S

EQ.

30N

2 14

8

b. March (CTL)

90W 45W 0 45E

30S

EQ.

30N

828

5

d. June (CTL)

90W 45W 0 45E

30S

EQ.

30N

5 2

f. September (CTL)

90W 45W 0 45E

30S

EQ.

30N

5

11 8

h. December (CTL)

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30S

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30N

200

600

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30S

EQ.

30N

a. March(PMS)−March(CTL)

90W 45W 0 45E

30S

EQ.

30N

b. March(PVE)−March(CTL)

90W 45W 0 45E

30S

EQ.

30N

c. Sept.(PSS)−Sept.(CTL)

90W 45W 0 45E

30S

EQ.

30N

d. Dec.(PWSol)−Dec.(CTL)

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90W 45W 0 45E

30S

EQ.

30N

a. March(PMS)−March(CTL)

90W 45W 0 45E

30S

EQ.

30N

b. March(PVE)−March(CTL)

90W 45W 0 45E

30S

EQ.

30N

c. Sept.(PSS)−Sept.(CTL)

90W 45W 0 45E

30S

EQ.

30N

d. Dec.(PWSol)−Dec.(CTL)

�1

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90W 45W 0 45E

30S

EQ.

30N14

8

42

−10−10

−2

−4

a.June−March T

sfc (CTL)

90W 45W 0 45E

399

3

−3 −9−9

−3

b. June−March P (CTL)

90W 45W 0 45E

30S

EQ.

30N6

26

2

6

−8

−4

−2

−2

c.Sept.−March T

sfc (CTL)

90W 45W 0 45E

3

939

−3−9 −9

−3−3

−3

d. Sept.−March P (CTL)

90W 45W 0 45E

30S

EQ.

30N

2

2−8

−2

−2

−2

e.Dec.−March T

sfc (CTL)

90W 45W 0 45E

93

33

−3

−3−3

f. Dec.−March P (CTL)

−6 0 6

sw′TOA

sst′

−200 0 200

30S

15S

EQ

15N

30N

−9 0 9

sw′TOA

sst′

−50 0 50

30S

15S

EQ

15N

30N

−3 0 3

sw′TOA

sst′

−200 0 200

30S

15S

EQ

15N

30N

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30S

EQ.

30N 42

2

−2

−2

a. June−March (PVE)

90W 45W 0 45E

44

22

−2−2

b. June−March (PWSol)

90W 45W 0 45E

30S

EQ.

30N

6

64

2−2

−2−6

c. Sept.−March (PVE)

90W 45W 0 45E

4

8

64

−4 −2

−6

d. Sept.−March (PWSol)

90W 45W 0 45E

30S

EQ.

30N 2

2−2

−2

e. Dec.−March (PVE)

90W 45W 0 45E

2

−2

−2

f. Dec.−March (PWSol)

−6 0 6

30S

15S

EQ

15N

30N

J−M sst′

−9 0 9

30S

15S

EQ

15N

30N

S−M sst′

−3 0 3

30S

15S

EQ

15N

30N

D−M sst′

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90W 45W 0 45E

30S

EQ.

30N

3

3

−3

−3

a. June−March (PVE)

90W 45W 0 45E

93 3−3

−3 −3

−3

b. June−March (PWSol)

90W 45W 0 45E

30S

EQ.

30N

399

−3

−3

−3

c. Sept.−March (PVE)

90W 45W 0 45E

39 3

−3

−3 −3

−9

d. Sept.−March (PWSol)

90W 45W 0 45E

30S

EQ.

30N

3 3

−3−9

e. Dec.−March (PVE)

90W 45W 0 45E

93

−3

−3−3

f. Dec.−March (PWSol)

−6 0 6

30S

15S

EQ

15N

30N

J−M sst′

−9 0 9

30S

15S

EQ

15N

30N

S−M sst′

−3 0 3

30S

15S

EQ

15N

30N

D−M sst′

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30S

EQ.

30N12

2

−2

−6

−8

a. June−March (PMS)

90W 45W 0 45E

8

2

−8

−10

−6

b. June−March (PSS)

90W 45W 0 45E

30S

EQ.

30N

6

2 2

−2

c. Sept.−March (PMS)

90W 45W 0 45E

4

2

2

−2

−4

d. Sept.−March (PSS)

90W 45W 0 45E

30S

EQ.

30N

2

−10

e. Dec.−March (PMS)

90W 45W 0 45E

2

4 2

−8

f. Dec.−March (PSS)

−200 0 200

30S

15S

EQ

15N

30N

J−M sw′TOA

−50 0 50

30S

15S

EQ

15N

30N

S−M sw′TOA

−200 0 200

30S

15S

EQ

15N

30N

D−M sw′TOA

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30S

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30N

3

93 −3

−3−3

−9

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3

3

−9−3 −3

b. June−March (PSS)

90W 45W 0 45E

30S

EQ.

30N

33 −3

−3

−3

c. Sept.−March (PMS)

90W 45W 0 45E

33−3

−3

d. Sept.−March (PSS)

90W 45W 0 45E

30S

EQ.

30N

3

93

−3−9

−3

e. Dec.−March (PMS)

90W 45W 0 45E

3

3

9

3

−9−3−3

f. Dec.−March (PSS)

−200 0 200

30S

15S

EQ

15N

30N

J−M sw′TOA

−50 0 50

30S

15S

EQ

15N

30N

S−M sw′TOA

−200 0 200

30S

15S

EQ

15N

30N

D−M sw′TOA

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30S

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30N

June − Factor:SST

90W 45W 0 45E

30S

EQ.

30N

June − Factor:Insolation

90W 45W 0 45E

30S

EQ.

30N

June − Interaction

90W 45W 0 45E

30S

EQ.

30N

Sept. − Factor:SST

90W 45W 0 45E

30S

EQ.

30N

Sept. − Factor:Insolation

90W 45W 0 45E

30S

EQ.

30N

Sept. − Interaction

90W 45W 0 45E

30S

EQ.

30N

Dec. − Factor:SST

90W 45W 0 45E

30S

EQ.

30N

Dec. − Factor:Insolation

90W 45W 0 45E

30S

EQ.

30N

SAT

Dec. − Interaction

�1

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30S

EQ.

30N

June − Factor:SST

90W 45W 0 45E

30S

EQ.

30N

June − Factor:Insolation

90W 45W 0 45E

30S

EQ.

30N

June − Interaction

90W 45W 0 45E

30S

EQ.

30N

Sept. − Factor:SST

90W 45W 0 45E

30S

EQ.

30N

Sept. − Factor:Insolation

90W 45W 0 45E

30S

EQ.

30N

Sept. − Interaction

90W 45W 0 45E

30S

EQ.

30N

Dec. − Factor:SST

90W 45W 0 45E

30S

EQ.

30N

Dec. − Factor:Insolation

90W 45W 0 45E

30S

EQ.

30N

PRECIPITATION

Dec. − Interaction

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15S

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15N

30N

Control − 1st EOF of PRECIP (56%)a.

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−1

−0.5

0

0.5

1

1.5

21st PCb.

90W 60W 30W 0 30E

30S

15S

EQ.

15N

30N

Varying Insolation Only − 1st EOF of PRECIP (70%)c.


−1

−0.5

0

0.5

1

1.51st PCd.

90W 60W 30W 0 30E

30S

15S

EQ.

15N

30N

Varying SST Only − 1st EOF of PRECIP (65%)e.


−1

−0.5

0

0.5

1

1.51st PCf.

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30S

15S

EQ.

15N

30N

45Na. Precipitation due to the Sep−Mar SST

120W 90W 60W 30W 0 30E 60E 45S

30S

15S

EQ.

15N

30N

45Nb. Precipitation due to Convec. Htng Alone

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15S

EQ.

15N

30N

45Na. P−E due to the Sep−Mar SST

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30S

15S

EQ.

15N

30N

45Nb. P−E due to Convec. Htng Alone

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60N

a.

45W 0 45E 90E

30S

EQ.

30N

60N

b.

45W 0 45E 90E

30S

EQ.

30N

60N

c.

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320

340

360

West Africaa.

Sept. SLP Sept. θe

March SLP March θe

1005

1015

1025

30S 15S EQ 15N 30N1005

1015

1025

300

320

340

360

Central Africab.

Sept. SLP Sept. θe

March SLP March θe

1005

1015

1025

30S 15S EQ 15N 30N1005

1015

1025

−20

−10

0

10

20

30c.

Sept.−March SLP Sept.−March θe

30S 15S EQ 15N 30N−4

−2

0

2

4

6

−20

−10

0

10

20

30d.

Sept.−March SLP Sept.−March θe

30S 15S EQ 15N 30N−4

−2

0

2

4

6

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Change Forced by Insolation

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30N

Change Forced by Africa+S.America Heating

Precip & V850

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300 320 340 360

200

400

600

800

1000

June Insolationa.

300 320 340 360

200

400

600

800

1000

March Insolation c.

−4 −2 0 2 4

200

400

600

800

1000

Difference a.−d.e.

θθ

eθ

es

300 320 340 360

200

400

600

800

1000

June Africa+S.America Qb.

300 320 340 360

200

400

600

800

1000

Perpetual Marchd.

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200

400

600

800

1000

Difference b.−d.f.

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eθ

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30N

Land (June−March) Condensational Heating at 500mb

−2 −1 0 1

200

400

600

800

1000

S.America J−M Qcond

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30S

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30N

a. Prescribed March SST

90W 45W 0 45E

30S

EQ.

30N

c. Interactive (March) SST

90W 45W 0 45E

30S

EQ.

30N

b. Prescribed Sept SST

90W 45W 0 45E

30S

EQ.

30N

d.

Precipitation & Wind Anomalies due toJun−Mar Land Condensational Heating

Interactive (Sept) SST

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10S

5S

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10N

15N

Precipitation a.


15S

10S

5S

EQ

5N

10N

15N

Surface Temperture & Wind b.


15S

10S

5S

EQ

5N

10N

15N

Total Heat Flux into the Surfacec.


15S

10S

5S

EQ

5N

10N

15N

Wind Speed Squared d.

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90W 45W 0 45E

30S

EQ.

30N

CTL−LPVE March

266

10 10

−2−6

−10

−2

a.

90W 45W 0 45E

30S

EQ.

30N

CTL−LPVE June

2060

100

−20−60−100

−140

−100−60−20

b.

90W 45W 0 45E

30S

EQ.

30N

CTL−LPVE September

26

−2−6−10

−14−18

−22−18−14

−10−6

c.

90W 45W 0 45E

30S

EQ.

30N

CTL−LPVE December

202060

100 10060

−20 −20−60

−100

−140

d.

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90W 45W 0 45E

30S

EQ.

30N

CTL−LPVE Marcha.

90W 45W 0 45E

30S

EQ.

30N

CTL−LPVE Junec.

90W 45W 0 45E

30S

EQ.

30N

CTL−LPVE Septembere.

90W 45W 0 45E

30S

EQ.

30N

CTL−LPVE Decemberg.

90W 45W 0 45E

CpldCTL−CpldLPVE Marchb.

90W 45W 0 45E

CpldCTL−CpldLPVE Juned.

90W 45W 0 45E

CpldCTL−CpldLPVE Septemberf.

90W 45W 0 45E

CpldCTL−CpldLPVE Decemberh.

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15S10S 5S EQ 5N10N15N

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Control

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Oceanic Forcings Only


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SST & V CpldCTLc.


SST & V CpldLPVEd.

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30S

EQ.

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CpldCTL−CpldLPVE: March SAT

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EQ.

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60W 30W 0 30S

EQ.

30N

c. CTL−LPVE Jan LHFLX & Vsfc

60W 30W 0 30S

EQ.

30N

e. CTL−LPVE Feb LHFLX & Vsfc

60W 30W 0

b. CpldCTL−CpldLPVE Dec LHFLX & Vsfc

60W 30W 0

d. CpldCTL−CpldLPVE Jan LHFLX & Vsfc

60W 30W 0

f. CpldCTL−CpldLPVE Feb LHFLX & Vsfc

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−10

−5

0

5

SAHA

RA T

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)

CpldPVE−CpldCTL

a.


−1

0

1

2

NTA

Wsf

c(m/s

)

b.


−0.9

−0.6

−0.3

NTA

T sfc

(K)

c.


−1

−0.5

0

0.5

NTA−

STA

T sfc(K

) d.


−6

−3

0

V=O

line

(lat)

e.


−9

−6

−3

0

P=m

ax lin

e (la

t) f.

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15S10S 5S EQ 5N10N15N

PREC CpldLPVEQflux

Varying Ocean Insolation Only

a. PREC CpldLOPVE

Varying Q−flux Only

b.


15S10S 5S EQ 5N10N15N

SST & V CpldLPVEQfluxc.


SST & V CpldLOPVEd.

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20S

EQ.

20N

Controla. PREC: annual harmonic

20S

EQ.

20N

Controlb. SAT: annual harmonic

20S

EQ.

20N

Varying Land Insolation Onlyc. PREC: annual harmonic

20S

EQ.

20N

Varying Land Insolation Onlyd. SAT: annual harmonic

20S

EQ.

20N

Varying Ocean Forcings Onlye. PREC: annual harmonic

20S

EQ.

20N

Varying Ocean Forcings Onlyf. SAT: annual harmonic

20S

EQ.

20N

Varying Ocean Insolation Onlyg. PREC: annual harmonic

20S

EQ.

20N

Varying Ocean Insolation Onlyh. SAT: annual harmonic

20S

EQ.

20N

Varying Q−flux Onlyi. PREC: annual harmonic

20S

EQ.

20N

Varying Q−flux Onlyl. SAT: annual harmonic

20S

EQ.

20N

Varying Land Precipitation Onlym. PREC: annual harmonic

20S

EQ.

20N

Varying Land Precipitation Onlyn. SAT: annual harmonic

90W 45W 0 45E

20S

EQ.

20N

Varying Land Temperature Onlyo. PREC: annual harmonic

90W 45W 0 45E

20S

EQ.

20N

Varying Land Temperature Onlyp. SAT: annual harmonic

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