north pacific oceanic variability

North Pacific oceanic variability

報告人：沈茂霖　　　　 (Mao-Lin Shen)

112/04/21

Seminar report

112/04/21 Mao-Lin Shen, Dept. of Atmospheric Sciences, NTUMao-Lin Shen, Dept. of Atmospheric Sciences, NTU Page 2

Qiu’s papers

Qiu, B. and S. Chen (2010) "Interannual-to-Decadal Variability in the Bifurcation of the North Equatorial Current of the Philippines." JPO, accepted.

Qiu, B. and S. Chen (2010) "Interannual Variability of the North Pacific Subtropical Countercurrent and Its Associated Mesoscale Eddy Field." JPO, 40(1), 213-225.

Qiu, B. and S. Chen (2010). "Eddy-mean flow interaction in the decadally modulating Kuroshio Extension system." DSR-II, 57(13-14): 1098-1110.

112/04/21 Mao-Lin Shen, Dept. of Atmospheric Sciences, NTUMao-Lin Shen, Dept. of Atmospheric Sciences, NTU Page 3

(Qiu and Chen, 2010)

•North Equatorial Current bifurcation (NECB)

•Zonally distributed wind stress curl

112/04/21 Mao-Lin Shen, Dept. of Atmospheric Sciences, NTUMao-Lin Shen, Dept. of Atmospheric Sciences, NTU Page 4

STCC

•STCC, subtropical countercurrent

•Ekman convergence forcing, which associated with meridional temperature gradient and zonal geostrophic velocity

(Qiu and Chen, 2010)

112/04/21 Mao-Lin Shen, Dept. of Atmospheric Sciences, NTUMao-Lin Shen, Dept. of Atmospheric Sciences, NTU Page 5

Fig. Comparison between the interannually-varying Ekman forcing term and the interannually-varying EKE time series in the STCC band.

112/04/21 Mao-Lin Shen, Dept. of Atmospheric Sciences, NTUMao-Lin Shen, Dept. of Atmospheric Sciences, NTU Page 6

Fig. Comparison with Nino 3.4 and WP indices.

112/04/21 Mao-Lin Shen, Dept. of Atmospheric Sciences, NTUMao-Lin Shen, Dept. of Atmospheric Sciences, NTU Page 7

(Qiu and Chen, 2010)

Fig. (B) Eddy kinetic energy calculated from the satellite altimeter SSH data from October 1992 to September 2008. White contours denote the 4000-m isobaths..

112/04/21 Mao-Lin Shen, Dept. of Atmospheric Sciences, NTUMao-Lin Shen, Dept. of Atmospheric Sciences, NTU Page 8

112/04/21 Mao-Lin Shen, Dept. of Atmospheric Sciences, NTUMao-Lin Shen, Dept. of Atmospheric Sciences, NTU Page 9

Fig. (A) Lagged correlation between the SSHa (32o-34oN) and the one-year running mean PDO index. (B) Same as (A) except for the negative, one-year running mean NPGO index. Shaded regions indicate negative correlation coefficients.

112/04/21 Mao-Lin Shen, Dept. of Atmospheric Sciences, NTUMao-Lin Shen, Dept. of Atmospheric Sciences, NTU Page 10

112/04/21 Mao-Lin Shen, Dept. of Atmospheric Sciences, NTUMao-Lin Shen, Dept. of Atmospheric Sciences, NTU Page 11

112/04/21 Mao-Lin Shen, Dept. of Atmospheric Sciences, NTUMao-Lin Shen, Dept. of Atmospheric Sciences, NTU Page 12

Modeled correlation map observation correlation map

Fig. Correlation map of modeled Kuroshio transport and modeled SSHa (left) and that of observed Kuroshio transport (Johns et al., 2001) and SSHa.

112/04/21 Mao-Lin Shen, Dept. of Atmospheric Sciences, NTUMao-Lin Shen, Dept. of Atmospheric Sciences, NTU Page 13

Modeled Kuroshio transport

Fig. Determining modeled Kuroshio transport from SSHa.

37 37.5 38 38.5 39 39.5 40 40.5 4110

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Time (year)

Q (

Sv)

Kuroshio transportGrostrophic transport

37 37.5 38 38.5 39 39.5 40 40.5 4110

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Sv)

Kuroshio transportFitted transport

112/04/21 Mao-Lin Shen, Dept. of Atmospheric Sciences, NTUMao-Lin Shen, Dept. of Atmospheric Sciences, NTU Page 14

Kuroshio transport

1994.8 1995 1995.2 1995.4 1995.6 1995.8 1996 1996.2

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Time (year)

Q (

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Kuroshio transportGeostrophic transportFitted transportTransfered transport

1994 1996 1998 2000 2002 2004 2006 200810

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Q (

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Geostrophic transportFitted transportTransfered transport

Fig. Determining Kuroshio transport from AVISO SSHa.

112/04/21 Mao-Lin Shen, Dept. of Atmospheric Sciences, NTUMao-Lin Shen, Dept. of Atmospheric Sciences, NTU Page 15

Luzon Strait Throughflow

37 37.5 38 38.5 39 39.5 40 40.5 41-5

0

5

Time (year)

Q (

Sv

)

LS throughflow

Fig. Modeled Luzon Strait throughflow and the correlation map with SSHa.

112/04/21 Mao-Lin Shen, Dept. of Atmospheric Sciences, NTUMao-Lin Shen, Dept. of Atmospheric Sciences, NTU Page 16

Thank you for your attention.