%hign ciJu & Trao dd'i
DANH GIA SAI SO D ^ BAO DlJOfNG DI CUA BAO BANG DV BAO TO H 0 P TREN KHU Vl^C
TAY BAC THAI BINH DlJOfNG TRONG CAC NAM 2003 - 2006.
ThS. Nguy§n Dang Quang
Trung tam Du" bao JQii tifdng Thuy van Trung u'dng.
_ _ ^ di bdo Id ke't qud ciia mot nghien ciiu ve ddnh gid sai sddu bdo dudng di ciia bdo kill dUa m-^tJiem mot hoac nhieu dudng trung binh to hop vdo he thdng dU bdo td hop nghiep vu (ggi la J—J^ Control) tgi co quan khi tuOng Hdng Cdng. Vdi bdn ndm sd lieu, 2003-2006, ket qud dif bdo cua tap hop mdi (sau khi bd sung mot hogc nhieu dudng trung binh vdo Control) khong dua lai nhifng cdl thien ddng ke ve sal sdvl tri trifc tie'p DPE, ngoai trU tgi thJl diem T+120h, sai sd'DPE gidm 4-6% nhun^
cdl thien ndy cdng khong thda mdn kiem nghiem t-test. Tuy nhien, khi xet khd ndng bao phii cila tap hop mdi vdi dudng dl "that" ciia bdo (best-track), tap hop mdi chi difbao .sal 15% trong khi con so ndy ciia Con- trol Id 40% tgi hgn difbao T-\-120h. Do tdn cda tap hgp khdng dii khd ndng cung cap do tin cay ciia difbao.
Sal sdve hudng doc theo dUcJng dl chuyen (AT) va hudng vudng gdc vdi du<yng dl chuyen (CT) cila bdo cdng dugc xem xet trong nghien citu. Sal sd ciia AT Idn h<fn .sal sd ciia CT; cd Control vd tap hgp mdi deu chi ra xu hudng dif bdo thien lech phdi vd cham ddn theo thdi gian so vdi Best - track.
1. Gidfi thieu
NhO'ng danh gia ve do chinh xac ciia difbao durdng di ciia bao bang dif bao td hdp da dufdc tie'n hanh bdi Goerss(2000), Aberson(2001)...
Cac nghien ciiii nay chii trong nhieu de'n tinh ifu viet cua dif bao td hdp, vi du nhu* sai sd dif bao ciia td hdp thi nhd hdn sai so' dif bao ciia ttog thanh phan trong td hdp dd (Goerss 2000) hoac chat lu'dng dif bao td hdp tai ban T+72h tang trung binh 2.4% mot nam ke til' 1976 de'n nay (Aberson 2001).... Tuy nhien, chifa cd nghien cii^i nao difdc thifc hien vdi each dat bai toan la xem xet sai so chung ciia tap hdp khi bd sung them mot hoac nhieu du'dng trung binh vao td hdp ban dau.
Cu the hdn, hien nay cd quan Khi tu'dng Hong Cdng (HKO) dang siJ dung trong nghiep vu dif bao bao thong tin td hdp tii' bdn mo hinh
tat dinh ciia Cd quan Khi tifdng Anh Qud'c (UKMO), Trung tam dif bao Mdi tru'dng My (NCEP), Cd quan Khi tifdng Nhat Ban (JMA) va Trung tam DiJ bao ban vijfa Chau Au (ECMWF). Tii" nay, trong bai bao nay, chiing tdi goi td hdp bdn md hinh nay la Control. Ben canh viec thu nhan du'dc ke't qua tiJ bd'n md hinh tren, HKO cdn nhan du'dc san pham dif bao td hdp cua JMA va ECMWF khi cd bao, ap tha'p nhiet ddi (ATND) tren khu vifc Tay Bac Thai Binh Difdng. Nghien ciJu se tim hieu viec bd sung them du'dng trung binh chung (SEM, Simple Ensemble Mean) du* bao td hdp ciia JMA va ECMWF vao Control cd lam tang chat lifdng dif bao hay khdng, vdi han dif bao la 120h. Ke't qua du" bao du'dc so sanh vdi vi tri
"thifc" ciia bao (best-track); thdi gian bao dich chuyen giila hai diem gan nhau nha't trong Best-track la 6h.
Ngtfdi phan bien: TS. Nguy§n Thi Minh Phtfofng
20 Tap chi Khi ivO^wg Thuy van * Thang 5/2008
Nghi§n ctfu & Trao ddi
Hai thanh phan thifdng difdc diing trong viec danh gia difbao du'dng di ciia bao la sai so' vi tri trifc tie'p (DPE) va sai so' theo hufdng AT/CT dufdc sii" diing trong nghien ciJu. Ben canh dd, trong cdng tac nghiep vu dif bao Khi tifdng viec tim ra sai so he thd'ng ciia md hinh hoac ciia td hdp mo hinh la rat hiiXi ich; viec lam nay trtfc tie'p anh hu'dng de'n chat lifdng ban tin. Phan cudi ciia bai bao de cap de'n van de nay.
2. Sai so'drf bao
Cac dif bao du'dng di ciia bao trong Control du:dc thu thap trong bd'n nam 2003-2006 tren toan khu vifc Tay Bac Thai Binh Du'dng. Moi xoay thuan nhiet ddi, bao gdm ca nhifng nhilu dong nhiet ddi cd vi tri tam xac dinh va td'c do gid be mat ctfc dai nhd hdn 17m/s (63]cm/h) deu dufdc thu thap va danh gia trong bai bao.
Cac dif bao trong Control difdc so sanh vdi best-track; best-track ciia HKO la qua trinh tdng hdp va phan tich cac ngudn thdng tin cd difdc sau khi cdn bao ke't thiic. Thdi han difbao la 120h, cac tinh toan du'dc thifc hien tren cac
tap mau ddng nha't. Suf can thie't ciia viec phai suf dung cac tap m l u ddng nha't du'dc gidi thieu bdi Neumann va Pelissier (1981b).
Trong hai nam 2003-2004, san pham difbao td hdp EPS ciia Nhat Ban ma HKO nhan du'dc la 25 thanh phan, HKO khong nhan du'dc san pham EPS ciia Trung tam difbao han vii'a Chau Au (ttj" nay goi tat la Chau Au) trong nhffng nam nay. Tff nam 2005, HKO thu nhan dffdc lien tuc va deu dan 51 thanh phan EPS ciia ca Nhat Ban va Chau Au.
a. Sai sd'vi tri triic tie'p DPE
Sai so vi tri trffc tie'p dffdc dinh nghia la khoang each giffa dff bao va quan trac ciia mot cdn bao (Neumann va Pelissier, 1981b). Bang 1 dffdi day chi ra DPE trung binh va do lech chuan (STDEV) ciia Control va tap hdp mdi.
Tap hdp mdi la Control ke't hdp vdi mot hoac nhieu SEM ciia mot hoac nhieu td hdp dff bao.
Cu the hdn, SEM cua dff bao td hdp ciia Nhat Ban dffdc tinh cho bd'n nam 2003-2006, SEM ciia dff bao td hdp ciia Chau Au dffdc tinh cho hai nam 2005 - 2006.
Bang 1. DPE trung binh vd dg l^ch chudn (dUgc ghi trong dau () ben canh gid tri DPE) (km) trong cdc so sanh dong nhat: la) Control(C) vdC + SEM ciia JMA EPS 2003-2006 vd lb) tUdng tUla nhUng them C + (SEM cua ECMWF) vd C + (SEM cda JMA) + (SEM cua ECMWF) trong hai ndm 2005- 2006. DLM: Dung lUgng mdu
Bang l a
Bang 1b
03-06 24h 48h 72h 96h 120h
Control(C) 105.281 (70.36) 174.68(110.12) 230.88 (136.67) 275.28(169.13) 289.53 (163.86)
C-HJMA S H M
110.41(72.22) 182.47(116.86) 230.33(138.33) 266.53(152.05) 283.57(159.57)
DLM 435 346 255 174 99
05-06 24h 48h 72h 96h 120h
Control(C) 98.22 (59.15) 170.19(100.73) 216.83 (124.54) 271.54(182.94) 277.51 (138.07)
C-f-ECM SEM 99.95 (64.18)
169.67 (103.55) 219.03 (128.28) 270.73 (164.83) 297.92(131.34)
C-KJMA SEM
102.51 (63.56) 176.05(111.73) 213.14(125.33) 258.62 (144.36) 264.78 (127.27)
C - I - E C M + J M A
102.93 (66.48) 168.59 (103.52) 215.24 (129.41) 255.39 (146.95) 265.30 (123.53)
DLM 188 148 110 72 35
Tap chi Khi tif<^ng Thuy van * Thang 5/2008
21Nghien cuTu & Trao doi
Cac ke't qua tren cho ta tha'y, DPE va STDEV la so sanh dffdc trong ca Control va tap hdp mdi. Trong 24h dff bao dau tien, DPE va STDEV ciia tap hdp mdi ludn Idn hdn Con- trol mac dii sff Idn hdn nay la khdng dang ke.
Sff khac nhau giffa Control va tap hdp mdi la khdng rd rang nhffng tff thdi diem T-i-96h dff bao, chiing ta tha'y xua't hien mot xu hffdng thay ddi ve sai sd. Tff T+96h, sai so' vi tri trffc tie'p va do lech chuan giam 4-6% so vdi Con- trol. Tuy nhien nhffng cai thien ve sai so dff bao nay khdng thda man Idem nghiem thdng ke t-test cho tffng cap (paired t-test) d ca mffc tin cay 99% va 95%.
b. Sai so AT/CT
Viec tach sai sd dff bao ra hai thanh phan, sai sd theo hffdng doc dffdng di (AT) va sai so theo hffdng vudng gdc dffdng di (CT) ciia bao, lan dau tien dffdc dffa ra bdi Neumann va Pehssier(1981b). Thanh phan CT cho ta biet sai sd vi tri, thanh phan AT cho bie^t sai so theo thdi gian. Vdi viec xet dau ciia AT/CT, ta cd the danh gia dffdc dff bao lech trai hay lech phai (CT>0: dich chuyen trai, CT<0: dich chuyen phai), hoac dff bao cham hay nhanh (AT>0: nhanh, AT<0: cham) so vdi best-track.
Bang 2(a,b) neu mot so' dac tinh ciia Control va dff bao td hdp ciia Chau Au. Trong nghien cffu nay, chiing tdi dffa ra mot khai niem mdi:
mot td hdp dff bao dffdc xem la dff bao diing khi best-track nam trong vung bao phii ciia td hdp dd, dff bao la sai khi best-track khdng thuoc pham vi bao phu ciia chum td hdp.
Dffa vao viec phan tich quan he giffa AT/CT ciia md hinh tat dinh trong Control va SEM ciia dff bao td hdp tai trung tam tffdng ffng, chiing tdi da cdgang tim Idi giai thich cho ket qua ciia muc 2.1. Cu the, thanh phan AT/CT tff md hinh difbao bao ciia JMA va ECMWF trong Control dffdc so sanh vdi AT/CT ciia SEM ciia JMA EPS va ECMWF EPS. Cac kiem tra cheo ciing dffdc tie^n hanh, tffc la AT/CT tff md hinh tat dinh cua JMA dffdc so vdi AT/CT ciia SEM ciia ECMWF EPS; va ngffde lai AT/CT tff md hinh tat dinh ciia ECMWF dffdc so vdi AT/CT ciia SEM ciia JMA EPS. Ke't qua cho tha'y, he so tffdng quan tai T-f24h ciia md hinh va trung binh chung td hdp dff bao ciia cung mot trung tam la 0.7, trong khi dd he sd'nay la 0.4 hoac 0.3 khi kiem tra cheo (hinh l).pifa vao he sd tffdng quan cao giffa md hinh va trung binh td hdp ciia tffng trung tam, ta cd the suy nghi la ca hai trung tam Nhat ban va Chau Au deu xay dffng he thd'ng dff bao td hdp dffa tren mot
"nhan" md hinh; vdi "nhan" md hinh nay, bang cac each khac nhau ho xay dffng dffdc td hdp dff bao, hien nay sd' thanh vien trong td hdp dff bao ciia hai trung tam nay la bang nhau va bang 51 thanh phan.
Nhff vay, viec bd sung mot thanh phan cd tffdng quan cao (phu thuoc) vdi mot thanh phan trong Control se khdng giup tap hdp mdi giam sai sd. Dieu nay trung vdi phong doan ciia Bur- ton (2006), td hdp dff bao dffdc coi la td't nha't khi cac thanh vien trong dd la doc lap.
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22
Tap chi Khi tuf<;ng Thuy van * Thang 5/2008
Nghien cufu & Trao dd'i
SEM EPS-eoo
R'
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an - K » ; : :.•'?5'i-^•/^>
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R'= 0,382
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J?in/j la. Hai hinh tren ciing minh hoa tUdng quan cua AT(trdi), CT(phdi) giita SEM cua JMA EPS vd mo hinh td't dinh JMA. Hai hinh dUdi minh hoa tUOng quan gida SEM cda JMA EPS vd mo hinh td't dinh ECMWF, T+24h.
SEM
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Hinh lb. NhU hinh la nhUng tgi T+120h. Chi Men thi thdnh phdn AT, thdnh phdn CT co dgng tUdng tu.
Sau nam ngay, T+120h, he sd' tffdng quan trd nen rat nhd (0.1 hoac 0.2) ngay ca khi xet he so' nay giffa md hinh tat dinh va td hdp dif bao dffa tren "nhan" md hinh tat dinh dd. Sff
ddc lap giffa md hinh va he thd'ng dff bao td hdp trd nen rd rang, cac thanh phan sai so' ve hffdng ciia ca Nhat Ban va Chau Au la tffdng dffdng nhau. (hinh lb)
Bang 2a. Sai so'AT/CT 2003 - 2006 cua Control (C) vdi vi?c chgn cdc dung lUffng mdu dong nha't. So' trong cdc cot Nhanh/Chdm, Phai/Trdi vd Dung Id sdlugng cdc thdnh vien cda to hgp thda mdn vi§c xet ddu. Vidu tgi bang 2a, trong bdn ndm 2003-2006, tgi hgn dii bdo T+24h co tong cgng 1516 thdnh vien cho du bdo nhanh (AT>0).
(C) 24h 48h 72h 96h 120h (C) 24h 48h 72h 96h 120h
AT(2003-2006) STDEV(Trung binh)
145.81(-34.25) km 203.16(-77.99) kin 272.68(-114.52) km 312.46(-128.61) km 334.79(-152.69) km
Nhanh(N) 1516 1059 770 436 281
Cham (C) 2329 2021 1519 895 615
Dung 633 490 356 202 135
N/C 0.65 0.52 0.51 0.49 0.46
% S a i 40.45 43.48 47.80 60.08 62.71 CT(2003-2006)
STDEV(Trung binh) 109.69(-6.84) km 158.15(-4.56) km 202.79(-2.27) km 243.52(3.94) km 270.35(27.83) km
Phaii (P) 1782 1497 1121 650 473
Trai (T) 2063 1583 1168 681 423
Diing 631 486 387 225 143
p/r
0.86 0.95 0.96 0.95 1.12
% S a i 40.64 43.94 43.26 55.53 60.50
DLM 1063 867 682 506 362 DLM 1063 867 682 506 362
Tap chi Khi ttfgfng Thuy van * Thang 5/2008
23Nghien ctfu & Trao doi
Bang 2b. NhUbdng 2a nhiing dot vdi 51 thdnh phdn cua dUbdo tdhgp CUM ECMWF.
ECM EPS
24h 48h 72h 96h 120h ECM EPS
24h 48h 72h 96h 120h
AT(2005-2006) STDEV(Trung binh)
108.27(-38.15) km 168.24(-104.47) km 197.02(-156.45) km 196.28(-205.85) km 224.50(-250.58) km
Nhanh(N) 7812 5251 3348 1832 991
Cham(C) 13082 10717 7852 5332 3320
Diing 356 305 229 167 108
N/C 0.60 0.49 0.43 0.34 0.30
% S a i 15.04 8.41 9.84 10.22 14.29 CT(2005-2006)
STDEV(Trung binh) 111.01(-31.91) km 141.22(-34.89) km 165.92(-24.48) km 187.59(-7.95) km 182.81(17.58) km
Phai (P) 8563 6912 5152 3493 2254
Trai (T) 12331
9056 6048 3671 2057
Dung 340 301 233 166 113
P/T 0.69 0.76 0.85 0.95 1.096
% S a i 18.85 9.61 8.27 10.75 10.32
DLM 419 333 254 186 126 DLM
419 333 254 186 126
Phan tram difbao sai ciia Control ty le thuan vdi ban difbao, tff 40% tai T-i-24h tang len xap xi 60% tai T+120h dd'i vdi ca AT/CT. Mot sff tffdng phan Idn ve ty le dff bao sai d td hdp dff bao ciia Chau Au va Nhat Ban (khdng neu trong bang 2) da dffdc ghi nhan, cac td hdp dff bao nay chi sai dffdi 15% cho tdi tan T+120h.
Mot dieu Icha thii vi cung dffdc riit ra tff viec phan tich sai so': trong 24h dff bao dau tien, sai sd ciia JMA EPS nhd hdn nhieu lan so vdi sai sdciia ECMWF EPS. Chi 5-6% cac dff bao td hdp ciia Nhat Ban hi sai trong Idii sai sd'nay la 15-20% dd'i vdi dff bao td hdp ciia Chau Au.
Dieu nay ly giai bdi Cd quan Khi tffdng Nhat Ban cd sff dung sd dd cai xoay nhan tao tai thdi diem phan tich. Tuy nhien, Idi ich ciia viec cai xoay cung chi phat buy tac dung trong 24h dff bao dau tien, tff T-f24h trd di sai so' cua he
thd'ng difbao td hdp ciia Nhat Ban va Chau Au la nhff nhau.
c. DQ tdn cua tdhgp
Do tan da dffdc de cap trong nhffng nghien cffu ve do chinh xac ciia dff bao td hdp. Do tan dffdc dinh nghia la khoang each trung binh ciia cac thanh vien tdi dffdng trung binh td hdp (Go- erss, 2000). Mot td hdp dff bao cd cac thanh phan dffng hdp lai gan nhau (do tan nhd), dffdng best-track cd the gan dffdng trung binh chung td hdp (DPE nhd) hoac xa dffdng trung binh chung td hdp (DPE Idn). Tffdng tff the, mot td hdp cd do tan Idn cung cd hai tinh hudng vdi DPE: DPE nho hoac DPE Idn (hinh 3). Nhff vay, thffc sff khd cho ngffdi lam dff bao khi mud'n sff dung tham sd do tan nhff mot cdng cu cung cap do tin cay ciia dff bao td hdp.
600 300 -g400
2
* 3 0 0 200 100
72hJMAEPS
24 Tap chi Khi ttf<;ng Thuy van * Thang 5/2008
Nghidn cuiU & Trao doi
1(c) (d)
Hinh 3. Minh hoa do tdn vd DPE tgi T+24h (trdi) vd T+72h (phdi) cua JMA EPS. Hai diem nam trong hinh tron dUgc lay ngdu nhien sao cho DPE Idn md dg tdn nho, tUdng Ung vdi hai cdn bdo dhinh dUdi.
Hinh (c) Id mgt ATND ye'u, T+24h, thdi diem bat ddu dii bdo Id 12UTC14/02/2004; hinh (d) Id cdn bdo MELOR T+72h, thdi diem bdt ddu dUbdo Id 12UTC 31/10/2003. Dudng mdu xanh dUdng la dUdng trung binh chung cua tdhgp. Vi tri quan trac thiic cua dp thap (c) Id hinh tron mdu den, best-track cua MELOR (d) Id dUdiig lien net mdu den.
Trong nghien cffu nay, chung tdi cung tim hieu dac diem ciia nhffng he thd'ng cd do tan nhd ma sai so DPE Idn. Nhieu lffa chon ngau nhien dffdc thffc hien sao cho lffa chon dd thda man do tan nhd, DPE Idn. Ke't qua phan tich cho tha'y, da so' cac he thd'ng thda man dieu kien tren (DPE Idn, do tan nhd) hoac la mot he thd'ng ye'u hoac la mot he thd'ng manh di chuyen ngffde len cac vung vT do cao. Hinh 3 la hai vi du minh boa cho ke^t luan nay. Hinh ben trai phia dffdi la mot he thd'ng xoay thuan ye'u tai T+24h, thdi diem bat dau dff bao la 12UTC ngay 14/02/2004, hinh ben phai phia dffdi la cdn bao MELOR T+72h, ddi hffdng va di chuyen ngffde len vung vi do cao, thdi diem bat dau dff bao la 12UTC ngay 31/10/2003. Do tan va sai so' vi tri trffc tie'p ciia he thdng ye'u neu tren lan Iffdt la 121.38kin va 542.51km;
trong khi nhffng sd' nay ciia bao MELOR la 170.75km va 732.44km.
3. Sai s6'he thong
Trong cdng tac nghiep vu difbao Khi tffdng, viec tim ra sai so he thdng cua difbao dffdng di ciia bao la quan trong, chung giiip nang cao chat Iffdng cac ban tin. Xem xet tdi cac ty so ciia cac dff bao Nhanh/Cham, Phai/Trai trong bang 2, ca Control cung nhff dff bao td hdp ciia Nhat Ban va Chau Au chi ra mot xu hffdng khdng ddi, mang tinh he thd'ng la cac dif bao thien ve ben phai ciia best-track va cham dan theo thdi gian.
Gia tri do lech chuan va trung binh cua hai thanh phan sai sd AT/CT trong Control, JMA EPS va ECMWF EPS dffdc phan tich. Bang 3 hien thi ke't qua md hinh dff bao tat dinh ciia Nhat Ban va Chau Au trong Control. D l nhan tha'y, dung sai cua thanh phan AT Idn hdn dung sai ciia CT trong sudt thdi ban T+120h difbao.
Bang 3. Dg lech chuan vd gid trf trung binh (dUgc ghi trong ddu () ben canh gid trf dg lech chudn) (km) cda AT/CT trong mo hinh tdi dfnh cua Chau Au vd Nhat Bdn trong Control, 2003-2006
AT 24h 48h 72h 96h 120h
ECMWF 176.40(-56.26) 199.90(-110.21) 257.54(-159.71) 304.92(-l 70.84) 333.19(-183.87)
JMA 142.38(-20.22) 198.90(-57.33) 266.99(-101.86) 306.72(-100.53) 327.37(-129.91)
CT 24h 48h 72h 96h 120h
ECMWF 124.26(-27.81) 160.84(-22.49) 197.19(-20.40) 246.18(-15.64) 279.16(-18.49)
JMA 105.29(-7.0) 155.14(-9.43) 201.08(-8.72) 240.10(-16.04) 259.86(-22.91)
Tap chi Khi ttfQfng Thuy van * Thang 5/2008
25Nghien cuTu & Trao doi
Nhff vay, ngffdi lam dff bao tai cd quan Khi tffdng Hong Cdng hoan toan cd the sff dung nhffng ket qua nay de bieu chinh san pham tff td hdp dff bao hien thdi.
4. Ket luan
Phan dau ciia nghien cffu danh cho viec danh gia sai so' dff bao khi them mot hoac nhieu thanh phan trung binh tff cac dff bao td hdp ciia Nhat Ban va Chau Au vao control.
Viec lam nay khdng cai thien dffdc chat Iffdng dff bao neu sff dung tieu chi danh gia la sai so' vi tri trffc tiep. Bai bao ciing Icbao sat kha nang bao phii ciia tap hdp mdi dd'i vdi best-track.
Tap hdp mdi cd kha nang dffa ra dff bao dung tdi 85% khi so vdi 40% difbao diing ciia td hdp cu tai han difbao T-i-120h. Phan tich do tan va hai thanh phan sai sd AT/CT ciia tap hdp dffdc thffc hien d phan hai ciia bai bao. Do tan khdng dffdc xem la mot chi tieu tin cay trong viec dff bao dffdng di ciia bao. Mot each cd he thd'ng, sai so' theo thdi gian AT Idn hdn sai so' theo hffdng CT; ca td hdp difbao mdi ciing nhff con- trol deu cho cac dff bao cd xu hffdng dich
chuyen ve ben phai so vdi best-track va cham dan theo thdi gian.
Chffdng trinh danh gia dff bao dffdng di ciia bao dffdc viet bang ngon ngff lap trinh Fortran tren nen Linux. Chffdng trinh nay da dffdc kiem dinh, hien dang dffdc tham khao tai bo phan nghien cffu F3 cd quan khi tffdng Hong Cdng. Chung tdi cho rang chffdng trinh nay hoan toan cd the ap dung trffc tiep cho cdng tac danh gia difbao dffdng di cua bao tai Trung tam Dff bao Khi tffdng Thiiy van Trung ffdng.
Ben canh do, chffdng trinh dffdc xay dffng theo hffdng md va nghien ctiii tie'p theo se hffdng tdi bai loan dff bao nghiep vu.
5. Lcfi cam dn
Tac gia chan thanh cam dn Ong Chan Sai - Tick, ngffdi chiu trach nhiem Idioa hoc ciia noi dung nghien cffu. Tac gia cung xin dffdc cam dn nhffng gdi y mang tinh dinh hffdng ciia Ong Edwin Lai, trffdng bo phan nghien ciJu F3, cho bai bao nay. Nghien cffu dffdc thffc tai ciia cd quan Khi tffdng Hong Cdng vdi ma so'
100/188/1 Pt.7.
T a i lieu t h a m k h a o
1. Aberson, S. D., 2001: The ensemble of Tropical Cyclone Track Forecasting Models in the North Atlantic Basin (1976-200). Bull. Amer. Meteor Soc, 82, 1895-1904.
2. Andrew, B., P. Caroff, J. Franklin, E. Fukada, T. C. Lee, B. Sampson and T. Smith, 2006: Sharing experiences in operational consensus forecasting. WMO/CAS/WWW Sixth International Workshop on Tropical Cyclones. 424-441.
3. DeMarla, M., S. D. Aberson, K. V. Ooyama, and S. J. Lord, 1992: A nested spectral model for hurricane track forecasting. Mon. Wea. Rev. ,120, 1628-1643.
4. Elsberry, R.L., and J.E. Peak, 1986: An Evaluation of Tropical Cyclone Forecast Aids Based on Cross-Track and Along-Track Components. Mon. Wea. Rev., 114, 147-155.
5. Goerss, J. S., 2000: Tropical Cyclone Track Forecasts Using an Ensemble of Dynamical Models.
Mon. Wea. Rev.,128, 1187-1193.
6. Neumann, C. J., and J. M. Pelissier, 1981b: Models for the prediction of tropical cyclone motion over the North Atlantic: An operational evaluation. Mon. Wea. Rev.,109, 522-538.
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