1. 1
1 1 Roger Lukas2
3 3 Jing-Jia Luo4 1 1
1JAMSTEC-RIGC, Yokosuka, Japan,
2University of Hawaii-Manoa, Honolulu, USA,
3JAMSTEC-ESC Yokohama, Japan
4JAMSTEC-RIGC, now at Bureau of Meteorology/Australian Government
JpGu 2012 22

3. - -
e.g., Lukas1988;
Ueki et al. 2003)
I
SST →
(e.g., Lindzen and Nigram 1987; Eisenman et al. 2005; Gebbie et al. 2007)
→ SST

4. - -
(1)
(2)

5. ≈≈≈
- -
#
* CTD R/V
* TMI)
* QuickSCAT
not shown here
#
* OFES
- 0.1 ° x 0.1 °
- 3
- MOM3,
- QuikSCAT NCEP/NCAR (1999-2004)
Masumoto et al. 2010

6. ≈≈≈
- -
2002/03

7. -Background- Coastal upwelling along Papua New Guinea
Coastal upwelling along Papua New Guinea (New Guinea)
→Generating relatively cool SST
Western equatorial Pacifc
Existence of New Guinea coastal
upwelling
e.g., Lukas1988; Ueki et al. 2003)
Purpose of the present study
# To check existence of New Guinea coastal upwelling before onset of El Nino
# To explore a mechanism of SST cooling related to New Guinea coastal upwelling
New
Guine
a
Pacific warm pool
Westerly wind
Bismarck Sea

8. 2.7˚S EQ
CTD
28
2002/03
CTD
80m
20m
CTD
2002/03
TMI-SST
SST
Hasegawa et al. 2009 JO

9. 2001 12 22
→
(Lukas1988; Webster & Lukas 1992)
SST ( ) & SSW 2001 12 22

10. TMI-SST
2001
2
SST :
( )
SST
Hasegawa et al. 2009 JO

11. SST
SST )
SST →
SST
→ SLP
→
(e.g., Kessler&Kleeman 2000)
(m/s:140-160E)
SST:
( )
(150-160E minus 140-150E)
SST:
SST
Hasegawa et al. 2009 JO
2001

12. OFES

13. OFES SST/
OFES SST
Hasegawa et al. 2011 JPO
1999-2004
&
Alongshore
163%

14. ●
●

15. : (SINTEX-F2)
150
[ 0.5°x0.5°; SINTEX-F (Luo et al. 2010)]
(C): #23540519
SST
SST (model time; 62 )
SST

16. : (iRAM)
SST
(C): #23540519

17. The OFES hindcast experiments were conducted at the Earth Simulator Center
with the support of JAMSTEC.
The cruise of the R/V Kaiyo (KY0111) was conducted under the Tropical Ocean Climate
Study (TOCS) of JAMSTEC.
Published paper concerning this study:
Hasegawa, T., K. Ando, K. Mizuno, and R. Lukas (2009):
“Coastal upwelling along north coast of Papua New Guinea and SST cooling over Pacific warm pool:
A case study of 2002/03 El Nino”, Journal of Oceanography, vol. 65, 817-833.
Hasegawa, T., K. Ando, K. Mizuno, R. Lukas, B. Taguchi, and H. Sasaki (2010):
“Coastal upwelling along the north coast of Papua New Guinea and El Nino events during 1981-2005”,
Ocean Dynamics, vol. 60, 1255-1269.
Hasegawa, T., K. Ando, and H. Sasaki (2011):
“Cold water flow and upper-ocean currents in the Bismarck Sea from December 2001 to January 2002”,
Journal of Physical Oceanography, vol. 41, 827-834.

18. Appendix

19. Observation:
Showing New Guinea coastal upwelling and related cool SST
in the late of 2001 to early 2002 prior to 2002/03 El Nino event.
However, observational data are limited:
# High resolution satellite data is obtained for 2000s
# Not many current velocity observation by moorings, R/Vs, etc.
Detail of surface current variations?
High resolution OGCM hindcast
# OFES QuikSCAT-run hindcast

20. fig07-map-snapshot-tmi-tot-uwin-
tot-vwin-tot-22dec2001-ver2
QuikSCAT
Surface wind
22DEC2001
NCEP1
Surface wind
22DEC2001

21. Heat balance in the south EQ in the Bismarck Sea
Heat balance during coastal upwelling period (Dec 2001-Jan 2002)
(BOX: 0 m to 30.8 m; similar current patterns are found in these depths)
Upwelled cool water transported equatorwards from coastal area
by the northeastward current can have
large cooling effect upon south EQ Pacific in the Bismark Sea
Bismarck Sea
New Guinea
Hasegawa et al. 2011 JPO
Residual: +0.057( )
Western Pacific: Relatively small SST change has a strong effect on climate
(Palmer and Mansfield 1984; Goddard et al. 2009 )

22. OFES: NCEP/NCAR forcing during 1981-2005
Masumoto et al. 2004, Sasaki et al. 2008)
Six El Nino events occur with coastal upwelling for 1981-2005
Composite maps of SST (color shade) and surface currents (arrows) for six New Guinea upwellings
prior to six El Nino onsets during 1981-2005
Hasegawa et al. 2010 OD
30 days before zero day
15 days before zero day
Zero day (day of coldest SST)
of New Guinea upwelling

23. OFES-QuikSCAT run (DEC2001-JAN2002) :
comparison to observation
SST&SSHA: OFES vs Obs
Surface current:
SADCP vs OFES
Hasegawa et al. 2011 JPO
OFES SSHA
Altimeter
SSHA
OFES SST
TMI SST
OFES QuikSCAT run
(Without any uning for Bismarck Sea)
QuikSCAT
RED: Observation (Shipboard ADCP)
BLUE: OFES

24. OFES-QuikSCAT run (DEC2001-JAN2002) :
comparison to observation
SST&SSHA: OFES vs Obs (Average: DEC2001-JAN2002)
Hasegawa et al. 2011 JPO
OFES SSHA
Altimeter
SSHA
OFES SST
TMI SST
Similar pattern
OFES : Without any uning for Bismarck Sea

25. Nino-3.4 index (OFES & Obs)
Hasegawa et al. 2010 OD
OFES well represent six El Nino events
(1982, 1986, 1991, 1997, 2002, and 2005)
The six events are used for composite analysis
OFES
Observation (Obs: OI-SST)

26. NOAA OI-SST
1981
12
1997
3
2001
12
1980
1982/83
1986/86
1991/91
1997/92
2002/03
1980
1982/83
1986/87
1991/92
1997/98
2002/03
5 3

27. Uwin
(raw)
Vwin
(raw)
( & 7 )
CTD
3 7
(e.g., Niller and Kraus 1977; Lukas 1988).
5S-3S, 140E-145E
2002/03
SST

28. Uwin
(raw)
Vwin
(raw)
( & 7 )
CTD
3 7
(e.g., Niller and Kraus 1977; Lukas 1988).
5S-3S, 140E-145E
2002/03
SST

29. -Summary and discussion-
zonal heat advection
SST cooling
Case study for New Guinea coastal upwelling, related surface currents and
SST cooling, prior to the onset of the 2002/03 El Nino, using observation & OFES
hindcast, and long-term analysis using OFES NCEP/NCAR run
New Guinea
positive zonal gradient of SST
& strong westerly surface wind
Complicated surface currents in the Bismarck Sea can contribute to SST cooling
in the south part of the equatorial western Pacific
Surface currents
Before onset of El Nino