Summary Report

Lecturer: Chia-Ping ChiangDate: 2009/Jun/25

Model Description~ The Whole Domain

The whole model domain covers entire North Pacific Ocean ranging from 100°E to 80°W and from 30°S to 60°N. A 1/4° horizontal resolution is used east of 150°E, while a finer horizontal resolution of 1/8° is used west of 150°E. The vertical resolution is linear-exponential stretched grid of 26 layers with a thickness of 6 meter in the top layer. Both domains use the same vertical grids.

Model bathymetry:

Interpolated from unfiltered ETOPO-5 depth data.

Supplemented with the Taiwan’s National Center for Ocean Research’s (NCOR) 1-minute high accuracy depth archive in the Asian Seas.

The surface wind forcing:

Interpolated monthly Hellerman and Rosenstein winds stress.

Surface sources of heat and fresh water:

The Levitus94 seasonal climatology is used to initialize the model.

The eddy viscosity (Ah, Av) and diffusivity (Kh, Kv) used in both domains are 20 m2/sec.

Model Validation~ The System Settings

Conservation of Mass

Momentum equations (Horizontal)

Hydrostatic equation (Vertical)

Equation of conservation of salt or energy (potential temperature)

Equation of State (EOS):

Model Validation~ The Governing Equations

0, ( , , )wu v V V

0

1h h h v

u p uu fv A u A

t x z z

V

0

1h h h v

p vv fu A v A

t y z

v

z

V

, or h h h v

ss K s K s S T

t z z

s V

pg

z

TS ,

Model Description~ The TAI Domain

PCM-1 ~ East of Taiwan

PN ~ East China Sea

TK ~ Tokara Strait south of Kyushu

PCM-5 (ASUKA) ~ South of Japan

34°N & 38°N ~ Southeast and East of Japan

Near PCM1 ~ East of Taiwan

WOCE: Mean volume transports during 1994/9-1996/5 were estimated to be 23.3 Sv with a standard error of 2.0 Sv. Max in July-August and Min in October.

Liu et al’s (1998): Mean transport estimate of 22.6 Sv from repeat CTD/ADCP sections.

Johns et al, (2001): 21.5 Sv with an uncertainty of 2.5 Sv.

Year 37-39, 5-day running mean

W. E. Johns et al., (2001)

Temporal Mean during Year 37-39.

Position & Magnitude

Mean downstream velocity structure during Sep 1994–May 1995.

Depth & Magnitude

Near PCM1 ~ East of Taiwan

Near PCM1 ~ East of Taiwan

Near PN ~ East China Sea

Oceanographic Division, Nagasaki Marine Observatory, JMA The long-term mean relative transport from 1973 to 2000 is 25.8 Sv with a mean

seasonal maximum of 27 Sv in summer and minimum of 23.9 Sv in autumn.

Year 37-39, 5-day running mean

CPIES+ADCP observation during October 2003 until November 2004 .

M. A

ndres et al. (2008)

Temporal Mean during Year 37-39.

E. O

ka et al. (2003)

Quarterly data of CTD and shipboard ADCP from 1987 to 1997.

Near PN ~ East China Sea

Near PN ~ East China Sea

Near TK ~ Tokara Strait South of Kyushu

Observation from spring 1987 to spring 2005 and many estimates of the Kuroshio volume transport through Tokara Strait ranges from 18 Sv to 32 Sv (Bingham and Talley 1991; Yamamoto et al., 1993; Nakano et al., 1994; Yamamoto et al., 1998; Feng et al., 2000; Zhu et al., 2006).

Year 37-39, 5-day running mean

Near TK ~ Tokara Strait South of Kyushu

E. Oka et al. (2003)

Near TK ~ Tokara Strait South of Kyushu

Year 37 Sep.

Year 38 Jun.

Year 39 Sep.

40 observations during 1987–97:

35/40 double current cores25 Stronger northern core (Type 1)10 Stronger southern core (Type 2)

5/40 single southern core (Type 3). There is no case of a single northern core.

Volume Transport

PCM-1

PN

TK

Three Typical Path of the Kuroshio

M. Kawabe (2005)

Non-large meander near-shore path

Non-large meanderoff-shore path

Large meander path

Kuroshio Path

Year 37 Sep.

Year 38 Jun.

Year 39 Sep.Non-Large

Off-shore Meander

Non-LargeMeander Transition

(Off to Near)

Non-Large Near-shore Meander