利用都卜勒雷達分析颱風風場結構 – 2001納莉颱風

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1 61 1 2* 1 2* 2009 (Da-Tun Rain Gauge Network, DTRGN) NCEP-FNL Froude number DTRGN [w s ][γ] [N] (R MAX ) w s γn 1 R MAX * yuku@faculty.pccu.edu.tw TEL:

2 62 Wu et al Yeh and Chen 2004 Yang et al Yu and Cheng Chien and Kuo 2011 Fang et al Huang et al Xie and Zhang (Yu and Cheng 2013 Yu and Cheng 2014) 2006 Yu and Cheng Z-R Battan Da-Tun Rain Gauge Network DTRGN CWB DTRGN NCEP-FNL DTRGN

3 63 ( ) 1 20 x 20 km m DTRGN 2 1

4 64 2 ( ) 1. DTRGN CWB DTRGN GPRS (General Packet Radio Service) TK-1 CTKF mm 80 mm hr %

5 65 2. NCEP-FNL NCEP-FNL NCEP-FNL EMC 1 x 1 21 (U) (V) 3 NCEP-FNL NCEP-FNL

6 66 NCEP NCEP-FNL ds083.2/ ( ) (Houze 1993) NCEP (convective available potential energy, CAPE; Weismen and Klemp 1982) (Convective inhibition, CIN; Colby 1984) (Browning et al. 1974; Hill et al. 1981) 1000 Froude number Fr = U/NH U N H Smith 1979 (Cressman 1959) 1 km x 1 km ( ) % 1 mm (66.7%) 12 (16.7%) 24 NCEP 18 NCEP 4a m s b NCEP m s m s x 10 2 s x 10 2 s 1 Fr

7 67 1 NCEP Fr(R MAX )

8 68 4 NCEP (a) half-bar 2.5 m s -1 full bar 5 m s -1 (b)

9 x 10 3 g kg x 10 3 g kg 1 80% Fr (Smith 1979; Houze 1993) DTRGN CWB DTRGN CWB DTRGN + CWB (a) CWB (1382 mm) (881.5 mm) 500 mm mm 100 mm 5(b) DTRGN + CWB (1327 mm) ( mm) mm mm 100 mm 5(a) 5(b) CWB DTRGN + CWB DTRGN+CWB 6 10 NCEP

10 (a)(cwb) (b) (DTRGN+CWB) mm 2

11 71 6 mm 2

12 72 6 ( )

13 a b 7c d 7e mm h mm h mm h 1 Yu and Cheng (2008) (Queney 1948; Scorer 1949) 9 (w s )(γ) (N) (R MAX ) w s γ N N 1 R MAX 9a-d 9a w s R MAX 0.31 w s R MAX 9b γ R MAX

74 7 (a) 10 20 (b) 20 30 (c) 30 40 (d) 40 50 (e) 50

14 74 7 (a) (b) (c) (d) (e) mm h -1 NCEP half-bar 2.5 m s -1 full bar 5 m s -1 2

15 75 8 mm h -1 2

16 76 8 ( )

17 77 9 (a) w s (b) γ (c) N (d) N 1 (e) w s γ (f) w s N 1 (g) γn 1 (h) w s γn 1 X Y (R MAX )

18 78 9 ( )

19 γ R MAX γ 9c N R MAX 0.37 N N 1 R MAX 9d 0.27 R MAX R MAX 9e-g R MAX 9e w s γ R MAX 0.16 w s N 1 γn 1 9f 9g R MAX h w s γn 1 R MAX 0.51 w s γn 1 R MAX h % T DTRGN CWB 18 NCEP 80% Fr ( ) DTRGN 10 R1 R2 S1 S2 S3 V 10 R1 R2 S1 S2 S3 10 V 10

20 80 w s γn 1 R MAX R1 R2 S1 S2 S3 V

21 81 - NSC M MY3 NSC M (TWD97) (TWD97) (m) ' 23.20" E 25 08' 10.30" N ' 14.50" E 25 09' 19.80" N ' 13.50" E 25 10' 33.90" N ' 40.16" E 25 11' 54.65" N ' 04.38" E 25 11' 30.22" N ' 09.53" E 25 13' 30.61" N ' 51.55" E 25 10' 41.29" N ' 05.19" E 25 12' 13.46" N ' 35.98" E 25 07' 46.18" N ' 40.00" E 25 12' 54.80" N ' 22.30" E 25 09' 29.51" N ' 24.10" E 25 08' 40.20" N ' 22.50" E 25 12' 21.00" N ' 04.30" E 25 13' 27.80" N ' 03.80" E 25 15' 46.50" N ' 09.00" E 25 12' 02.20" N ' 23.60" E 25 06' 35.30" N ' 38.10" E 25 09' 23.00" N ' 40.00" E 25 05' 20.30" N ' 48.90" E 25 05' 31.70" N ' 09.40" E 25 07' 41.90" N ' 58.70" E 25 12' 17.40" N ' 10.10" E 25 05' 51.80" N 51

22 X -SoWMEX/TiMREX IOP Battan, L. J., 1973: Radar Observation of the Atmosphere, Univ. of Chicago Press, Chicago, 793 pp. Browning, K. A., F. F. Hill, and C. W. Pardoe, 1974: Structure and mechanism of precipitation and the effect of orography in a wintertime warm sector. Quart. J. Roy. Meteor. Soc., 100, Chien, F.- C., and H.- C. Kuo, 2011: On the extreme rainfall of Typhoon Morakot (2009). J. Geophys. Res., 116, D05104, doi: / 2010JD Colby, F. P., Jr., 1984: Convection initiation as a predictor of convection during AVE-SESAME II. Mon. Wea. Rev., 112, Cressman, G. P., 1959: An operational objective analysis system. Mon. Wea. Rev., 87, Fang, X., Y.- H. Kuo, and A. Wang, 2011: The impacts of Taiwan topography on the predictability of Typhoon Morakot s recordbreaking rainfall: A high-resolution ensemble simulation. Wea. Forecasting, 26, Hill, F. F., K. A. Browning, and M. J. Bader, 1981: Radar and raingauge observations of

23 83 orographic rain over south Wales. Quart. J. Roy. Meteor. Soc., 107, Houze, R. A., Jr., 1993: Cloud Dynamics, Academic Press, 573 pp. Huang, C.- Y., C.- S. Wong, and T.- C. Yeh, 2011: Extreme rainfall mechanisms exhibited by Typhoon Morakot (2009). Terr. Atmos. Oceanic Sci., 22, Queney, P., 1948: The problem of airflow over mountains. A summary of theoretical results. Bull. Amer. Meteor. Soc., 29, Scorer, R. S., 1949: Theory of waves in the lee of mountains. Quart. J. Roy. Meteor. Soc., 75, Smith, R. B., 1979: The influence of mountains on the atmosphere. Adv. Geophys., 21, Weisman, M. L., and J. B. Klemp, 1982: The dependence of numerically simulated convective storms on vertical wind shear and buoyancy. Mon. Wea. Rev., 110, Wu, T.-H. Yen, Y.-H. Kuo, and W. Wang, 2002: Rainfall simulation associated with Typhoon Herb (1996) near Taiwan. Part I: The topographic effect. Wea. Forecasting, 17, Xie, B., and F. Zhang, 2012: Impacts of typhoon track and island topography on the heavy rainfalls in Taiwan associated with Morakot (2009). Mon. Wea. Rev., 140, Yang, M.-J., D.-L. Zhang, and H.-L. Huang, 2008: A modeling study of Typhoon Nari (2001) at landfall. Part I: Topographic effects. J. Atmos. Sci., 65, Yeh, H.-C., and G. T.-J. Chen, 2004: Case study of an unusually heavy rain event over Eastern Taiwan during the Mei-Yu season. Mon. Wea. Rev., 132, Yu, C.- K., and L.- W. Cheng, 2008: Radar observations of intense orographic precipitation associated with Typhoon Xangsane (2000). Mon. Wea. Rev., 136, Yu, C.- K., and L.- W. Cheng, 2013: Distribution and mechanisms of orographic precipitation associated with Typhoon Morakot (2009). J. Atmos. Sci., 70, Yu, C.- K., and L.- W. Cheng, 2014: Dual-Dopplerderived profiles of the southwesterly flow associated with southwest and ordinary typhoons off the southwestern coast of Taiwan. J. Atmos. Sci., in press.

24 84 Study of Intensive Rainfall Observations over Da-Tun Mountains: Distribution of Orographic Precipitation during the Northeasterly Monsoon Lin-Wen Cheng 1 and Cheng-Ku Yu 2 1 Graduate Institute of Earth Science, Chinese Culture University, Taipei, Taiwan 2 Department of Atmospheric Sciences, Chinese Culture University, Taipei, Taiwan (manuscript received 25 April 2014 in final form 28 May 2014) ABSTRACT Mt. Da-Tun Rain gauge network (DTRGN) had been initially constructed in Given very few rainfall stations over mountains, they usually cannot capture the detailed distributions of orographic precipitation. Mt. Da-Tun (DT) is located nearby the northern coast of Taiwan and frequently produces the rainfall maximum in the typhoon environments and during the northeasterly monsoon season. Therefore, this study had deployed automatic rain-gauge stations over DT, which can provide high temporal and spatial resolution of surface rainfall measurements over this barrier. The rain-gauge stations of DTRGN are mostly located over the potentially concentrated rainfall area such as those near the mountain crest and windward slopes. In this study, eighteen winter rainfall events associated with northeasterly monsoon flow during the period from January 2011 to February 2013 were chosen for detailed analysis. The primary focus of this study is on investigating the detailed aspects of the intense orographic precipitation over DT. NCEP-FNL data was also used in this study to describe the upstream conditions. This study also attempts to explore the relationship between upstream conditions and precipitation distributions. Upstream conditions associated with the studied evennts were characterized by nearly neutral convective instability, large Froude number, and moist northeasterly oncoming flow, implying the importance of orographically forced lifting on the development of precipitation. The analysis results show that the precipitation over mountains has considerable variations within a few kilometers. Local maxima of orographic precipitation were observed to occur over the windward slopes, near the mountain crest, and even the valley region. Our analyses indicate that the degree of the

25 85 precipitation enhancement over valley depends strongly on the wind direction of upstream oncoming flow. Examination of the correlation between upstream meteorological factors (wind speed [w s ], mixing ratio [γ], and static stability [N]) and the maximum of rainfall intensity (R MAX ) over mountains indicates that R MAX exhibits a general trend to increase with w s and N 1. Further statistical analysis indicates that w s γn 1 and R MAX have best correlation. The results from the study represent good references to the future forecast or research of winter orographic rainfall in Taiwan. Key Words: Orographic precipitation, Northeasterly monsoon rainfall

Z-I A b Z-I A b Z Z-I A A b Z-I Miller [5] Z i I i Z-I [6] Z-I Z-I Z-I Z-I Z I Wilson [7] 1970 [8] [9] 20.32% Sasaki [10] Nino- miya [11] [12]

Z-I A b Z-I A b Z Z-I A A b Z-I Miller [5] Z i I i Z-I [6] Z-I Z-I Z-I Z-I Z I Wilson [7] 1970 [8] [9] 20.32% Sasaki [10] Nino- miya [11] [12] 24 2 Vol.24, No.2 2008 04 JOURNAL OF TROPICAL METEOROLOGY Apr., 2008 1004-4965(2008)02-0147-09 1 2 2 3 3 (1. 310017 2. 100081 3. 325001) Z-I A b Z I (Haitang) (Matsa) Z-I Z-I P458.1.24 A 1 [1] [2] [3]