200520241 19 1 18
1993 850hPa 6 7 6 27 7 3 6 29 ( ) 250 200hPa
i iii 1 1 1.1...................................... 1 1.1.1................................. 1 1.1.2......................... 1 1.1.3........... 4 1.2...................................... 9 2 10 2.1 JRA-25...................................... 10 2.2...................................... 10 3 11 3.1.................................... 11 3.2........................................ 11 3.3................................... 14 3.3.1...................................... 14 3.3.2...................................... 15 3.3.3...................................... 15 3.3.4.................................... 15 3.4............................. 16 4 18 4.1.................................... 18 4.1.1......................... 18 4.1.2........................ 18 4.1.3...................... 21 4.2 h θ.................................. 21 4.3............................ 26 i
4.3.1 850hPa.......................... 26 4.3.2 250hPa........................... 32 4.3.3............................. 32 4.4.............................. 40 4.5........................... 44 4.6............................. 44 5 47 6 51 7 52 53 54 ii
1 850hPa................. 2 2 7.................................... 5 3 4............................ 6 4...................... 7 5 Ogura and Portis (1982)... 8 6 850hPa............... 12 7 GMS-4......................... 13 8............ 17 9 1993 6 28 7 1 850hPa...................................... 19 10 1993 6 28 7 1 130...................... 20 11 1993 6 28 7 1 200hPa 130................. 22 12 850hPa 200hPa 1993 6 7..... 23 13...................... 24 14 1993 6 7.................. 24 15 1993 6 7 ( ).... 25 16 850hPa........... 27 17 850hPa...... 28 18 850hPa...... 29 19 850hPa...... 30 20 850hPa 31 21 250hPa...... 33 22 250hPa...... 34 23 250hPa...... 35 24 250hPa 36 25............. 37 26............. 38 27............. 39 iii
28............... 41 29 250hPa..................... 42 30 1000hPa 250hPa...... 43 31 1000hPa 250hPa...... 43 32............. 45 33...................... 46 iv
1 1.1 1.1.1 5 6 7 Meiyu front (Baiu front) (Ninomiya and Akiyama, 1992) ( 1) 1.1.2 Akiyama (1973) 40 Ninomiya and Akiyama (1992) Akiyama (1973) ( ) 700hPa (Low Level Jet) ( ) 130 1
1 850hPa ( : 10knot) ( ) ( ) 1968 7 9 12GMT (Ninomiya and Akiyama, 1992, Fig. 5 ) 2
( ) Kato and Kodama (1992) Kato and Kodama (1992) 1979 5 (850hPa 700hPa ) 2 3 Ninomiya and Akiyama (1992) Zhou et al (2004) Baiu Meiyu front dew-point front( ) 115 dew-point front Meiyu front Meiyu front (2005) 1 (1997) 1993 7 3
( 2) 1993 60 ( ) 1.1.3 1993 ( ) frontogenetical function ( ) 3 4 ( 3, a d) SESAME(Severe Environmental Storms and Mesoscale Experiment- ) 16 14 NASA AVE(Atmospheric Variability Experiment- ) Ogura and Portis (1982) 1974 4 26 ( 4, 5) 5 (2005) 4
2 7 ( ) ( ) ( ) ( ) (19 ) ( 1997, 9 ) 5
(c) (d) 3 4 (a) (b) (c) (d) (c), (d) ( ) ( ) ( 2000, 8.5, 8.7, 8.9 ) 6
4 ( ) ( ) (Ogura and Portis, 1982, Fig. 22 ) 7
5 1979 4 26 02GMT 10 7 K km 1 s 1 (a) (b) (c) (d) (Ogura and Portis, 1982, Fig. 25 ) 8
Shapiro ( Colle, 2003) 1.2 1993 9
2 2.1 JRA-25 JRA-25(Japanese Reanalysis 25 years) ( ) 1979 1 2004 12 26 JRA-25 3 (, 2002) T106 40 ( 0.4hPa) JRA-25 Fiorino (2002) GRIB (WMO, 1994) 200 T (K) u,v (m s 1 ) ( 17 ) q (kg kg 1 ) ( 12 ) p (Pa s 1 ) ( 10 ) 2.5 2.5 1 4 ( 00,06,12,18 UTC ) 3 p 2 2.2 1993 6 7 1993 (6 8 ) 6 7 10
3 3.1 T (K) θ (K) θ e (K) q (kg kg 1 ) u,v (m s 1 ) p (Pa s 1 ) θ ( ) κ p 00 θ = T κ R d = 0.2859 p C p p 00 1000hPa θ e T LCL (K) T (K) T d (K) e (hpa) f ( ) (, 2000) T LCL = 2840/[3.5ln(T ) ln(e) 4.805] + 55 e q w e = (1/0.622)pq θ e = θ exp(2.675q/t LCL ) θ e 3.2 (front) 6 1993 6 30 00UTC 850hPa h θ 7(a) 7(b) 3 03UTC GMS-4 h θ h θ h θ = {( ) 2 ( ) 2 } 1/2 θ θ + (1) x y 850hPa h θ 11
100 60 110 120 130 140 150 160 170 180 190 60 50 297 50 0.027 0.024 40 40 0.021 288 0.018 30 306 297 30 0.015 0.012 20 306 306 306 20 0.009 0.006 10 100 10 190 0.003 110 120 130 140 150 160 170 180 6 1993 6 30 00UTC 850hPa ( : K km 1 ) ( K) 12
(a) (b) 図 7 1993 年 6 月 30 日 (a) 00UTC 地上天気図 (b) 03UTC GMS-4 赤外画像 (天気, Vol. 40, No. 12 より引用) 13
3.3 (frontogenetical function) ( 2000 Ogura and Portis, 1982 ) 3 F d dt hθ (2) p d dt = t + v h h + ω p (3) v h = ui + vj (2) (front-genesis) (front-lysis) F = + + + (4) = 1 2 hθ δ {( ) 2 ( = [D 1 θ 1 2 h θ x ( )( = 1 θ θ ω h θ p x x + θ ω y y { ( ) ( = 1 θ dθ + θ h θ x x dt y y ) 2 } ( θ + 2D 2 y ) dθ dt )} )( θ x )] θ y 3.3.1 u,v (δ = u/ x + v/ y) Randall (2003) 14
3.3.2 D 1 D 2 D 1 δ = u/ x + v/ y D 1 u x v y (stretching deformation) D 2 ζ = v/ x u/ y D 2 v x + u y (shearing deformation) 2 3(c) D 1,D 2 θ/ x θ/ y 3.3.3 2 3(d) θ/ p < 0 ω/ y < 0 ( ω/ y)( θ/ p) > 0 y 3.3.4 3(b) (dθ/dt)/ y > 0 dθ/dt(= Q) (3) dθ dt = θ t + v θ (= a Q) a v 3 θ/ t v θ t (v θ) t 1 : (v θ) t : (v θ) t+1 = 1 : 2 : 1 Q 15
3.4 850hPa 8(a) 6 15 18UTC 7 12 18UTC 8(b) 4.2 (2) t θ = d dt θ v h h θ ω p θ 2 3 5 + + + + 16
(a) 100 60 110 120 130 140 150 160 170 180 190 60 50 50 0.027 0.024 40 40 0.021 0.018 30 30 0.015 0.012 20 20 0.009 0.006 10 100 10 190 0.003 110 120 130 140 150 160 170 180 (b) 0.015 300hPa 850hPa 0.010 front 0.005 0.000 60 80 100 120 140 160 8 (a) ( ) 1993 6 30 00UTC 850hPa ( : K km 1 ) (b) 6 15 18UTC ( 60) 7 12 18UTC 300hPa 850hPa (K km 1 ) 06UTC 17
4 4.1 4.1.1 Ninomiya and Akiyama (1992) 6 28 00UTC 7 1 18UTC 4 9 (a) 850hPa 9 (b) 9 (c) 1g kg 1 ( 9, c) 4.1.2 10 (a) (c) 130 6 28 00UTC 7 1 18UTC (a) (c) 30 35 ( 10, c) ( 10, b) 700hPa 350hPa ( 10, c) 18
(a) (b) (c) 9 1993 6 28 00UTC 7 1 18UTC 850hPa (a) (K) (b) (kg kg 1 ) (c) (K) (a), (b), (c) (m sec 1 ) 19
(a) (b) (c) 10 1993 6 28 00UTC 7 1 18UTC 130 (a) (K) (b) (kg kg 1 ) (c) (K) (a), (b), (c) ( : m sec 1 p : hpa sec 1 ) 20
4.1.3 11(a) 6 28 00UTC 7 1 18UTC 200hPa 35 40 50 60 35 40 11(b) 9 130 11(c) 130 700hPa 200hPa 5 65 300hPa 4.2 h θ 12 850hPa ( h θ ) 200hPa 1993 6 7 30 45 h θ h θ 6 23 7 4 7 12 26 14 13 850hPa ( h θ ) 6 7 12 6 26 00UTC 7 2 18UTC ( 14 8, b ) (1997) 15 (a) (1997) (1 ) ( 15, b) 21
(a) (b) (c) 11 1993 6 28 00UTC 7 1 18UTC (a) 200hPa ( : m sec 1 ) (b) 200hPa ( : m sec 1 ) ( ) (c) 130 ( : m sec 1 ) ( : K) 22
12 850hPa ( : K km 1 ) 200hPa ( : m sec 1, ) 1993 6 7 23
100 60 110 120 130 140 150 160 170 180 190 60 50 50 40 40 30 30 20 20 10 100 10 190 110 120 130 140 150 160 170 180 13 Front time fluctuation (Jun,July) 0.005 0.004 East domain West domain daily mean front 0.003 0.002 0.001 0.000 0 5 10 15 20 25 30 35 40 45 50 55 60 day 14 1993 6 7 (K km 1 ) 24
(a) (b) 15 1993 6 7 (mm) (a) 100km 100km (b) 25
4.3 16 (a) (c) (a) (6 26 00UTC 27 18UTC) (b) (6 28 00UTC 7 1 18UTC) (c) (7 2 00UTC 7 2 18UTC) h θ (b) 130 170 30 40 h θ (a) h θ (b) (c) 4.3.1 850hPa 17 (a) (c) h θ 850hPa 18 (a) (c) 19 (a) (c) h θ 180 ( 17 18, a) h θ ( 17, a) h θ ( ) ( 18, a) 2 h θ ( 19, a) h θ 140 40 50 h θ ( 17 18, b) h θ h θ 2 h θ h θ 130 140 35 3 ( 19, c) 850hPa 3 ( 20-1 20-3) 26
(a) 100 60 50 110 120 130 140 150 160 170 0.006 180 190 60 50 0.024 40 40 0.020 30 0.006 0.006 0.006 0.012 0.006 0.006 0.012 30 0.016 0.012 20 20 0.008 10 100 110 120 130 Front 850hPa 1993 July 28_01 140 150 160 170 180 10 190 0.004 (b) 100 60 50 110 120 130 140 150 160 170 180 190 60 50 0.024 0.006 40 40 0.020 30 0.006 0.006 0.006 0.012 0.012 30 0.016 0.012 20 0.006 20 0.008 10 100 110 120 130 Front 850hPa 1993 July 02_02 140 150 160 170 180 10 190 0.004 (c) 100 60 50 110 120 130 140 0.006 150 160 170 180 190 60 50 0.024 40 0.006 0.006 40 0.020 0.016 30 0.012 0.006 0.006 30 0.012 20 0.006 20 0.008 10 100 10 190 0.004 110 120 130 140 150 160 170 180 16 (a) (6 26 00UTC 6 27 18UTC) (b) (6 28 00UTC 7 1 18UTC) (c) (7 2 00UTC 7 2 18UTC) 850hPa ( : K km 1 ) 27
(a) (b) (c) 17 850hPa ( : K km 1 ) ( : 10 7 K km 1 s 1 ) (a) (b) (c) 28
(a) (b) (c) 18 850hPa ( : K km 1 ) ( : 10 7 K km 1 s 1 ) (a) (b) (c) 29
(a) (b) (c) 19 850hPa ( : K km 1 ) ( : 10 7 K km 1 s 1 ) (a) (b) (c) 30
1 2 3 20 850hPa ( : K km 1 ) ( : 10 7 K km 1 s 1 ) 1 2 3 31
( 20-1) ( 20-2) 170 170 ( 20-3) 850hPa 4.3.2 250hPa 250hPa ( h θ ) 21 (a) (c) 22 (a) (c) 23 (a) (c) 40 6 ( ) 21 (b) 21 (c) ( 21, b 135 ) 6 ( ) 2 ( 23, b) ( 23, c) 3 24-1 24-3 ( 130 45 ) 4.3.3 25 27 h θ - ( 28) 7 2 6 28 7 1 25 (a) (b) h θ 50 200hPa 42 300hPa 32
(a) (b) (c) 21 250hPa ( : K km 1 ) ( : 10 7 K km 1 s 1 ) (a) (b) (c) 33
(a) (b) (c) 22 250hPa ( : K km 1 ) ( : 10 7 K km 1 s 1 ) (a) (b) (c) 34
(a) (b) (c) 23 250hPa ( : K km 1 ) ( : 10 7 K km 1 s 1 ) (a) (b) (c) 35
1 2 3 24 250hPa ( : K km 1 ) ( : 10 7 K km 1 s 1 ) 1 2 3 36
(a) (b) 25 ( : K km 1 ) ( : 10 7 K km 1 s 1 ) 130 160 (a) (b) 37
(a) (b) 26 ( : K km 1 ) ( : 10 7 K km 1 s 1 ) 130 160 (a) (b) 38
(a) (b) 27 ( : K km 1 ) ( : 10 7 K km 1 s 1 ) 130 160 (a) (b) 39
60 200hPa h θ 900hPa 800hPa ( 26, a) 300hPa ( 26, b) 2 500hPa 450hPa 300hPa ( 27, b) 28(a), (b) (a) 30 50 42 (b) 30 50 42 30 40 20 (a) (b) 10 4.4 4.3.1 850hPa 50 145 ( ) 250hPa 29 (a) (h) (6 26 00UTC 6 27 18UTC) 6 250hPa 6 26 12UTC 50 (6 28 00UTC 7 1 18UTC) 1000hPa 29 06UTC 250hPa 250hPa 1000hPa 30 31 30 250hPa 31 40
(a) (b) 28 ( : 10 7 K km 1 s 1 ( : m sec 1 p hpa sec 1 ) 130 160 (a) (b) 41
(a) (b) (c) (d) (e) (f) (g) (h) 29 1993 6 26 00UTC 6 27 18UTC 6 250hPa (gpm) 42
100 60 110 120 130 140 150 160 170 180 190 60 50 50 40 10300 120 40 10400 60 20 30 10500 10600 10700 10800 120 10900 11000 30 20 10 100 190 10 110 120 60 11000 10900 130 140 120 150 160 170 180 30 1000hPa ( ) 250hPa ( ) (gpm) 100 60 110 120 130 140 150 160 170 180 190 60 50 50 40 10300 40 10400 60 20 30 10500 10600 10700 10800 10900 11000 120 30 20 10 100 60 11000 120 190 10 110 120 130 140 150 160 170 180 31 1000hPa ( ) 250hPa ( ) (gpm) 43
4.5 32 (a), (b) 32 (a) 500hPa 4.6 8 (a) 33 (a) 33 (b) 2 33 (a) 850hPa 33 (b) 300hPa 0 2 0 44
(a) (b) 32 ( : 10 7 K km 1 s 1 ( : m sec 1 p hpa sec 1 ) ( : K km 1 ) (a) 110 135 (b) 135 160 45
(a) 2.0 2.0 1.5 1.5 frontogenetical function 1.0 0.5 0.0-0.5-1.0-1.5 divergence term deformation term tilting term diabatic term 1.0 0.5 0.0-0.5-1.0-1.5 advection -2.0-2.0 (b) Frontogenetical function time fluctuation 0626-0702 frontogenetical function 2.5 2.0 1.5 1.0 0.5 0.0-0.5-1.0-1.5-2.0-2.5-3.0-3.5-4.0 divergence term deformation term tilting term diabatic term 105 110 115 120 125 time 2.5 2.0 1.5 1.0 0.5 0.0-0.5-1.0-1.5 advection -2.0-2.5-3.0-3.5-4.0 33 6 26 00UTC 7 2 18UTC ( ) ( ) ( ) ( ) ( ) (10 7 K km 1 s 1 ) (a) 850hPa (b) 300hPa 46
5 JRA-25 1993 6 7 h θ 6 7 ( 12 14) 6 26 00UTC 7 2 18UTC (1997) (1997) 1993 6 30 7 4 ( 14) 6 850hPa 850hPa h θ ( 16 a c) 12 60 h θ 47
250hPa (Ninomiya, K. 1984; Ninomiya and Akiyama 1992; Kato and Kodama 1992 ) 12 2 48
40 Ninomiya and Akiyama (1992) Kato and Kodama (1992) Ogura and Portis (1982) ( 5, a d) Ogura and Portis (1982) ( 25 28 b) ( ) Ogura and Portis (1982) ( ) 1 ( 28) ( 4) ( ) 49
50
6 1993 6 7 6 26 00UTC 7 2 18UTC h θ h θ e 51
7 1993 1 1993 52
53
Akiyama, T. (1973) The large-scale aspects of the characteristic features of the Baiu front. Pap. Met. Geophys., 24, 157-188. Colle, B. A. (2003) Numerical simulations of the extratropical transition of Floyd (1999): structural evolution and responsible mechanisms for the heavy rainfall over the Northeast United States. Mon. Wea. Rev., 131, 2905-2926. Kato, K. and Y. Kodama (1992) Formation of quasi-stationary Baiu Front to the south of the Japan Islands in early may of 1979. J. Meteor. Soc. Japan., 70, 631-647. (1997) 1993 189 72p-87p Kato, T., M. Yoshizaki, K. Bessho, T. Inoue, Y. Sato and X-BAIU-01 observation group (2003) Reason for the failure of the simulation of heavy rainfall during X-BAIU-01 importance of a vertical profile of water vapor for numerical simulations J. Meteor. Soc. Japan., 81, 993-1013. (2005) 208 27p-51p (2000) 3 196pp Ninomiya, K. and T. Akiyama (1992) Multi-scale features of Baiu, the summer monsoon over Japan and the east Asia. J. Meteor. Soc. Japan., 70, 467-495. (2000) 289pp Ogura, Y. and D. Portis (1982) Structure of the cold front observed in SESAME-AVE and its comparison with the Hoskins-Bretherton Frontogenesis Model. Bull. Amer. Meteor. Sci., 39, 2773-2792. 54
Randall, A. D. (2003) Spherical harmonics and related topics. Depar. Atmos. Sci., 51-64. (2005) 210 83p-97p (2005) Shapiro 52 105-118. (2006) JRA-25 V05024 1-21 Zhou, Y., S. Gao and S.P. Shen (2004) A diagnostic study of formation and structures of the Meiyu Front System over east asia. J. Meteor. Soc. Japan., 82, 1565-1576. 55