KHOA HOC - CONG NGHE - MOI TRl/dNG
NHffNB ANH HirdNG B0I HIEN TlTtfNG EL-NINO TRONG VU OONG XUAN N A M 2010
Du bao vien : Nguyen Ngpc Khai Trung tam Khi tuong Thuy van tinh DakLik LMODAU
El-Nino la hien tugng dac biet cua thai tilt khi viing bien ngoai khoi Nam My am len hk thudng va xay ra vao g^n dip le Giang Sinh. Trong dd, tri sd dao dong nam (SOI) dugc dac trung bdi gia tri chenh lech ap suat khi quyin giiia hai tram Tahiti (17.5°S - 149.6°W) nam d Dong Nam Thai Binh Duong va Darwin (12.4°S-130.9°E) nam oTayBac nude Uc.
Khi SOI mang gia tri duong cao thi bilu hien cho qua trinh phat trien cua hien tugng La-Nina va khi mang gia tri am cao thi bieu thi cho qua trinh El-Nino xay ra.
Trong bai vilt "Mot s6 anh huong bdi hien tugng ENSO ddi vdi sir bien doi khi hau tai DakLak" ra s6 2 nam 2009 tren Tap chi KH&CN tinh DakLak, da thi hien rit rd sir bien ddi khi hau khi cd hien tugng El- Nino xuat hien. Va d day chiing toi mong muon khang dinh mot Ian niia moi quan he giua hien tugng El- Nino va sir biln ddi thdi tilt tai tinh DakLak, cu the dugc the hien trong nam 2010.
II. MOI QUAN HE G I C A E L - N I N O VA SlTBIEN DOI THCJI TIET NAM 2010 L El-Nino va va cac tri so
Southern Oscillation Index (SOI)
O
CO
-30 -40
2004 2005 2006 2007 2006 2009
, - - t - 4 . 1 ,i • f . . 1 . t I ^ 1 1 1 L . i i i i ' ' • • • ' *•
Jan Jan Jan J€m
Year
Jan Jan
Bieu dfi tri s6 dao dong nam (SOI) tir nam 2004-2009
BAN TIN THONG TIN KH&CN SO 01/2010
KHOA HOC - CONG NGHE - MOI TRUCJNG
Nhu chung ta da bilt, khi El-Nino xuat hien vdi mot s6 dac trung nhu khu vuc Chau My chiu anh hudng lu lut, trong khi dd khu vuc Chau A lai ganh chiu han han nghiem trgng, miia kho den sdm hon, nen nhiet tang cao va lugng mua thi sut giam.
El-Nino xuat hien tir khoang thang 6/2009 va keo dai den nay tiep tuc hoat dong trong nhirng thang tdi. Tieu bieu nhu, nhiing ngay cuoi thang 10 den dau thang 11, he thong gio miia tay nam nhanh chong dugc thay the bdi he thong gid miia dong bac va hoat dong on dinh, lam cho miia kho nam 2009-2010 den sdm hon trung binh nhieu nam (TBNN).
Nhin vao bilu d6 tren cho thay, cac dgt El-Nino tir 06/2004 - 05/2005; 05/2006 -10/2006 va 06/2009 - nay, chiing ta thay rang miia mua trudc do ket thuc sdm hon TBNN, it xuat hien mua trai miia, nen nhiet cao hon va lugng mua thi thap hon TBNN. Tieu bieu nhu miia kho nam 2004-2005 nhu sau.
Bang gia trj chuan sai nhiet do va luong mua trong dot El-Nino nam 2004-2005
Tram BMT
M'Drac
Lak
Budn Ho
Ea HTeo
Thang Nhiet
Mua Nhiet
Mua Nhiet
Mua Nhiet
Mua Nhiet
Mua
XI 0.4 -86.1
0.3 196.8
1.0 107.1
0.3 -97.2
0.7 -78.0
XII -0.3 -20.3
0.1 -184.1
0.1 -27.4
-0.2 -27.7
-0.1 -13.1
I -0.2 -3.9 0.0 -41.7
-0.2 -1.6 0.3 -4.8
0.2 -2.8
II 1.4 -4.3
1.6 9.4 1.2 -0.4
2.0 -7.4
1.8 -6.6
III -0.6 -32.2
0.1 -9.8 -0.1 -14.6
-0.4 -19.7
-0.5 -19.5
IV 0.1 _
0.3 _
0.8 _
0.0 32.3
0.3 -6.9
Ngoai ra, mot dieu dang chu y khac chinh la tinh bat thudng ciia thdi tiet khi xuat hien El-Nino. Mac dii bao va ap thap nhiet ddi (ATND) hoat dong tren Bien Dong it hon nhung cuong do manh hon, ve khong gian va thdi gian cung bat thuong hon. Cu the nhu, tir ngay 18 - 20/01/2010 da xuat ATND tren khu vuc Nam Bien Dong, di chuyen chu yeu theo hudng Tay Bac va do bg vao cac tinh tir Binh Thuan - Sdc Trang, gay mua tren dien rgng cho cac tinh Nam Trung Bg, Nam Bg va Tay Nguyen cd noi mua vira den mua to.
Nhu vay, ngoai cac quy luat khi hau chung, chiing ta can phai theo doi va nam bat dugc cac bat thudng khi ma khi hau toan cau ngay cang bien doi manh me hon.
2. Nhan d|nh tinh hinh thoi tiet nam 2010
Theo nhan dinh tir cac trung tam khi hau Idn tren the gidi, dieu kien El-Nino se tiep hoat dong trong 3 thang tdi va giam dan ve trung tinh trong cac thang tiep theo.
Do thi du bao nhiet do be mat bien (SST) tai viing NINO 3 cua My.
§ BAN TIN THONG TIN KH&CN SO 01/2010
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KHOA HOC - CONG NGHE - MOI TRUCJNG
Ngoai ra, chimg tdi da sir dung mot sd cong cu du bao cho hai yeu to nhiet do va lugng mua va cho ket qua tuong doi dong nhat vdi nhu:ng nhan dinh neu tren.
Dudi day la cac so lieu tinh toan du bao, nham du bao xu the CO the xay ra trong nhirng thang tdi. Dung phuong phap thong ke tuong quan giira hai yeu to nhiet do va lugng mua vdi nhiet do be mat nude bien (SST) tai vungNIN034.
GMAO CGCMvl Forecast initialized in Jan 2010
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XBTT Perl Ocean. AMIP almos, GLDASIand lens1-6) XBTT Ocean. NCEP anom atmos. GLDAS land (ens7-ii) XBTT Pert Ocean. MCEP anom atmos. GLDAS lano (ensl3.IS) XRTT Ocean, fun N C E P ^ l O S . GLDAS land (ens12) XRTTS Ocoan (»nst91 ^ ^ ^ ^ ^ f f c ^
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2009 200 Sep Z010 j a n may jm Sep
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Bang du bao nhiet do va luong mua trong 3 thang (II, III, IV) nam 2010 Yeu to
Tram BMT Budn Ho
M'DrSk Lak Ea H'Leo
Nhiet do CC) TBNN
24.5 22.4 23.5 24.5 23.3
Du- bao 25.0 23.0 24.0, 25.1 23.8
Chuan Sai 0.5 0.6 0.4 0.6 0.5
Lu-oTig mu-a (mm) TBNN
121.0 112.0 129.8 107.9 96.6
Dy bao 88.0 78.7 88.0 69.0 71.2
Chuan Sai -32.9 -33.3 -41.9 -38.9 -25.4
Tir ket qua tren cho thay, nen nhiet do trung binh trong 3 thang (II-IV) cd gia tri du bao la cao hon TBNN, ngugc lai tong lugng mua ciing trong 3 thang tren thi thap hon. Vdi ket qua tinh toan doc lap tren, chiing ta nhan thay rang cac dieu kien khi El-Nino hoat dong la phu hgp vdi quy luat.
HLKETLUAN
Miia kho nam 2009-2010 la miia kho ma chiu su anh hudng cua hien tugng El-Nino, vdi cac dac trung la nen nliiet tang cao va lugng mua sut giam, mua trai miia xay ra it va nang nhieu gay nen su thieu hut manh ve nguon nude.
Hien tai, tren cac song sudi nhd va vira dang d mire rat thap tren cac song Idn thi muc nude ciing nhu ddng chay se giam nhanh. Ngoai ra ciing can phai de cap din san xuSt nong nghiep d DakLak chii yeu la cay cong nghiep cd gia tri kinh te cao, san lugng cua cac loai cay trdng nay xk nhay cam vdi viec cung cap nude du hay thieu. Neu nguon nude tudi bi thilu se gay that thu va thiet hai kinh tl vd cimg Idn. Do vay can phai het sire tiet kiem nguon nude ngay tir dau vu va phai cd bien phap, kl hoach tich trii, sir dung nude hgp ly de dam bao yeu cau nude tudi cho cay cong nghiep va cho ca vu Ddng Xuan 2009-2010, tranh tinh trang thieu nude tram trgng c6 nguy co de dga din ca sinh hoat cho con ngudi va gia siic nhu vu Ddng Xuan nam 2004-2005 va mot s6 vu khac...
BAN TIN THONG TIN KH&CN SO 01/2010