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(1) Vien Khoa hgc Kiii tugng Ttiuy van va Bien doi tdiiiigu (2) Trung tam Dixiiao Khitugng Thuy van Trung gang T 6 M TAT. B^c diim khi hau Biin Bong duac ddnh gid dira tren chuoi so lieu cua 13 trgm ven bd vd cdc trgm ddo thdi ky 1961-2010. Phdn tich vd ddnh gid dugfc thuc hien cho 8 vung, bao gom 6 vung bien ven bcr vd 2 vung bien ngodi khen: Vung bien bdc vinh Bdc Bg, nam vinh Bdc Bg, tu Qudng Tri den Qudng Ngdi, tir Binh Binh den Ninh Thudn, tir Binh Thudn den CdMau, tir Cd Mau den Kien Giang, khu vuc qudn ddo Hodng Sa (vitng bien ngodi khoi bdc Bien Bone) vd khu vi£c qudn ddo Trudng Sa (vung bien ngodi khffi nam Bien Bong). Ket qud cho thdy cdc vung bien ven b& co dgc diem cff bdn cua viing khi hgu ven b& vd cUng mang nhimg net cda khi hgu hdi duffng. Vdng bien cdc qudn ddo Hodng Sa vd Tru&ng Sa mang dgc diem cua vdng khi hgu hdi duffng, the Men ro net Id co miia he mdt han vd miia dong dm han, nhiet do toi cao thu&ng thdp han vd nhiet do toi thap thu&ng cao han so v&i khi hau dat lien.
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Bien Ddng nam d phia Tay cua Thai Binh Duong. Cac vftng bien chu quyen thugc Biin Ddng ciia cac qudc gia ven bien dugc quy djnh theo Cdng udc cua Lien Hgp Quoc vi luat biin nam 1982. Dudng bd Bien Ddng cua Viet Nam cd chieu dai khoang 3260 km, keo dai qua 28 tinh, thanh phd. Biin Ddng cd hai vinh Idn la vjnh Bic Bg va vjnh Thai Lan. Diiu kien khi hau d vjnh BJe Bd chju anh hudng
manh me efta chg dd gid mua ddng bac va dja hinh ndng ven bd Viet Nam. Vjnh Thai Lan nam sau vao phia bd tay nam cua Bien Ddng, cd nhieu dao Idn trong dd cd dao Phu Qudc la dao Idn nhit ven bo Viet Nam. Hai quin dao Idn thudc chu quyen Viet Nam n jm trong Biin Ddng la quin dao Hoang Sa va qu&i dao Trudng Sa. QuSn dao Hoang Sa rgng khoang 14.000 km^ each Da Ning khoang 170 hai ly vi phia ddng. Tft quan dao Hoang Sa di vi
I w l Sothang8+9nam2014
H NGHIEN CUU - TRAO DOI
phia ddng nam khoang 300 hai ly la quan dao Trudng Sa vdi dien tich rgng khoang 180.000 km'.
Khi hau Biin Ddng da dugc phan tich trong mdt sd nghien ciiu. Pham Ngoc Toan va Phan Tat Dac (1993) da khai quat ve mien khi hau Bien Ddng, trong do coi khi hau cac dao gan bd mang dac diem chinh cua khi hau vftng dat lien ISn can vdi dao dd. Khu vyc ngoai khoi Bien Bdng, dugc xet nhu mgt mien khi hau rieng vdi hai vung bac Bien Ddng va nam Bien Ddng. Nhimg dac tnmg khi hau chmh cua vung bac Bien Ddng dugc danh gia dua tren sd lieu ciia tram dao Hoang Sa, vftng nam Bien Ddng dugc danh gia dya tren sd lieu cua tram dao Trudng Sa, day dugc danh gia la vung khi hau gid miia mang tinh chat xich dao rd ret. Mgt sd nghien ctru khac ve dac diem khi hau Bien Ddng nhu Atlas Khi tugng Thuy van Viet Nam (1994); Che do nhiet d Bien Ddng va Vjnh Thai Lan (Nguyen Vu Thi,
1986); Quy luat bien ddng eua mdt sd trudng khi tugng co ban vung bien Ddng (Bui Xuan Thdng, 2001).
Dya tren chudi sd lieu cap nhat den nam 2010 efta cac tram dao Viet Nam, ke ca tram dao ven bd va tram ngoai khoi, tinh chat efta mdt sd yeu td khi hau dugc phan tich va danh gia, vdi muc dich cung cap thdng tin chi tiet hon ve dac diem khi hau Bien Ddng.
2. Sd lieu va phirong phap 2.1. So lieu
Sd lieu dugc su dung bao gdm nhiet do trung binh thang, nhiet do tdi cao, nhiet do tdi thap, tdng lugng mua thang, do am trung binh thang, tdng lugng bdc hoi thang, tdc do gid trung binh, sd gid nang cua 13 tram khi tugng, khi hau ven bd va ngoai dao khu vuc Bien Ddng. Thdi ky sd lieu cua da phan cac tram la 1961-2010. Tuy nhien, mdt sd tram dao cd chudi sd lieu ngan hon van dugc su dmg.
Bdng 1. Danh sdch cdc trgm vd thdi ky lay sd lieu TT
1 2 3 4 5 6 7 8 9 10 11 12 13
Ten tram CdTd Cam Ranh Hdn DSu Bach Long VT Hdn Ngu CdnCd Hoang Sa Ly Son Trudng Sa Phft Quy Cdn Dao Phu Qudc Quy Nhon
V i a o ( N ) 20°59' 11°55' 20''40' 20°08' 18M8' 17°10' 16°33' 15''23' 08''39'
io°3r
08=14'
ion3'
13»46'
Kinh do (E) 107°46' 109°09' 106°48' 107''43' 105M6' 107»22' 111<'37' 109°08' 111°55' 108°56' 106°36' I03°58' 109n3'
ThM ky so lieu 1961-2010 1978-2010 1961-2010 1961-2010 1961-2010 1975 - 2010 1961 -1973 1984-2010 1978 - 2010 1980-2010 1961-2010 1979 - 2010 1961-2010
Sothang 8+9 nam 2014
•
h j e n viat Nam
2.2. Phuomgphdp
Phuong phap tmh cac dac teung thdng ke dugc sft dung pho biin ttong thdng ke khi hau bao gdm:
Trung binh sd hgc,
^ ^-liP'
Cue dai cua chuoi, Max (x):
Max(x) = x'^
Cue tieu cua chudi, Min (x):
Min(x) = X*, Trong do: t = thdi gian, Xj ^ sd heu quan ttac 3. Ket qua va thao luan
Dac diem khi hau Bien Ddng dugc danh gia qua dac diem khi hau cua 6 viing khi ban bien ven bd va 2 vftng khi hau bien ngoai khoi. Qua trinh phan vung nay co ban dua theo su phan vftng ttong ban dd du bao thdi tiet cac vung bien Viet Nam efta Tnmg tam Du bao Khi tugng Thfty van Trung uong, kit hgp vdi ngudn sd lieu hien cd. Khu vuc tinh toan bao gdm: Vung bien bac vjnh Bac Bd, nam vjnh Bac Bd, tu Quang Tri den Quang Ngai, tft Binh Djnh den Ninh Thuan, tft Binh Thuan den Ca Mau, tft Ca Mau den Kien Giang, khu vyc quan dao Hoang Sa (vung bien ngoai khoi bac Bien Ddng) va khu vue quan dao Tmong Sa (vftng bien ngoai khoi nam Bien Ddng)
3.1. Dgc diem khi hdu viing biin bac vinh BacBo
Che do nhiet: nhiet do d viing bien bac vjnh Bac Bd phan bd tuong ddi ddng nhat theo khdng gian. Nhiet dd khdng khi trung binh nam dao ddng trong khoang tft 22,5°C den 24,0°C; chenh lech nhiet dd giua thang ndng nhat va thang leinh nhat frong nam vao khoang 11,5 - 13,5°C. Nhiet do khdng khi frung binh thang lanh nhit dao ddng frong khoang tit 15,0 - 17,2°C. Nhiet do khdng khi ttimg bmh thang ndng nhat la 28,6 - 29,5"C. Nhiet do tdi thip trung binh va nhiet do toi cao trung binh frong cac thang miia he va cac thang mua ddng cd sy khac biet dang ke. Dao Bach Long Vl la noi cd nen nhiet do cao nhat frong vung. Nhiet do khdng khi tdi cao trung binh cua cac thang . tai tit ca cac fram khdng dudi 17,5°C vi cd tti sd trung binh frong thang ndng nhit (than^
VII) la 31,0 - 32,0»C. Nhiet do khdng khi tdi thap trung binh frong thang l^nh nhat (thang I) dao ddng ttong khoang 13,5 -15,6''C.
Che do mua vd cdc yeu td khdc: Lugng mua trung bmh nam dao dgng frong khoang tu: 1100 - 1700mm. Trong nam cd 4 - 5 thang cd lugng mua trung binh fren 200mm, 5 thang cd lugng mua tnmg binh dudi 50 mm. Mfta mua phd bien tft thang V den thang X frong dd mua nhiiu nhit vao 3 thang VII, VIII, DC. Trj sd phd bien cua do am tuong ddi trung binh nam la 84 - 85%. Lugng bdc hoi trung bmh nam dao dgng tft 750tnm din 1100mm, chi sd am uot nam la 1,5 - 2,0 Toe dp gid trung binh nam la 4,0 7,0 m/s va tdc do gid manh nhit
^,
ISothang8+9nam2014
I NGHIEN CUU - TRAO EOI
nam la 45 - 50 m/s, manh hon so vdi vung duyen hai frong dat lien.
3.2. Die diem khi hgu vung bien nam vinh Bdc Bo
Chi do nhiet: Trong cac thang mua ddng nin nhiet d vung biin nam vjnh Bac Bg cao hon so vdi vung bien bac vjnh Bac Bg, frong mua he thi ngugc lai. Nhiet do frong raua he d bic vjnh Bic Bd thip hon so vdi dat lien, ttong khi do nhiet do mua ddng cao hon so vdi dit liin. Vi vay nen bien dp nam efta nhiet do d ngoai vjnh nhd hon ttong dit lien.
Nhiet dp khdng khi trung bmh nam la 23,0 - 24,0°C, ttong thang ndng nhit (thang VII) la 29,0 - 29,5°C, ttong thang lanh nhit (thang I) la 17,0 - 17,5»C. Nhiet do tdi cao trung bmh tton^ thang ndng nhit la 32,5 - 33,0''C, nhijt do tdi thap tnmg binh ttong thang lanh nhat la 15,4°C. Nhiet dp cao nhat tuyet ddi khoang gin 40,0°C va nhiet dp thap nhit myet ddi xap xi 6,0''C,
Che do mua vd cdc yeu to khdc: Gia tri phd bien cua lugng mua trung binh nam la 1600 - 2000mm ttong dd cd 5 - 6 thang lugng mua trung bmh tten 100mm, khoang 4 thang lugng mua trung bmh dudi 50rmn. Mua mua pho biin tu thang V din thang X, mua nhieu nhit vao 3 thang VIII, DC, X, mudn hon so vdi viing bien bac vjnh BSe Bd mdt thang. Gia tri phd biin efta lugng bdc hoi trung binh nam la 800 - 930mm, do im tuong ddi ttimg bmh nam la 85 - 86%, chi sd am udt nam la 2,0 - 2,5. Tdc do gid trung binh nam la 2,0 - 4,0 m/s
va tdc do gid manh nhat la 50 - 60 m/s.
3.3. Dgc diem khi hgu vimg bien tit Qudng Tri den Qudng Ngdi
Chi do nhiet: Nhiet do khdng khi ttimg bmh nam dao ddng ttong khoang 25,0 27,0»C. Bien do dao ddng nam la 6,0 - 9,0<'C.
Trong vimg bien nay nhiet do phan bd theo khdng gian tuong ddi ddng deu frong cac thang mfta he. Cac thang ndng nhat la thang VI - VIH. Nhiet do khdng khi toi cao trung bmh frong cac thang khdng nhd hon 23,3°C, vdi gia tri tnmg binh frong cac thang ndng nhit la 3I,0°C - 33,0''C, Nhiet dp khdng khi tdi thip trung binh frong cac thang khdng nhd hon 19°C, vdi gia tri trung bmh frong thang lanh nhit (thang I) la 19,0 - 22,0°C.
Che do mua vd cdc yeu td khdc: Lupng mua trung bmh nam dao ddng frong khoang 2200 - 2400inm. Mua mua lui mudn hon so vdi vung bien bac va nam vinh Bac Bp, keo dai tft thang VIII nam trudc den thang I nam sau, frong dd mua tap trung vao cac thang IX, X, XI. Trong 3 thang nay lupng mua do dugc deu fren 300mm. So vdi hai vung biin thudc bic va nam vjnh BSc Bd thi d vung bien nay cd lugng mua ddi dao hon vi ca nam khdng ed thang nao lugng mua dudi 50 mm, frong khi dd cac vung bien fren cd tu 4-5 thang. Gia tri phd bien cua dp am tucmg ddi trung binh nam la 85%, lugng bdc hoi nam la 860 - 940nun va chi sd im udt la 2,2 - 2,8. Toe do gid tnmg binh nam la 3,5 - 4,5 m/s, tdc dp gid eye dai la 32 - 40 m/s.
Sothang8 + 9nam2014
^ e jeit^
vies Ham
3.4. Dgc diem khi hgu vung bien tit Binh Dinh den Ninh Thudn
Che do nhiet: Nhin chung khi hau vftng biin tir Bmh Djnh den Ninh Thuan tuong ddi mat me, khdng cdn miia ddng lanh. Gia trj trung bmh nam cua nhiet do d vung bien nay khoang 27,0°C. Bien do nam cua nhiet do tu 4,5 - 6,6°C. Nhiet dp cao nhat tuyet ddi khoang 39,0 - 40,0°C, vdi gia tti trung binh trong cac thang ndng nhat (thang VI-VIII) tit 33,0 - 35,0°C. Nhiet dp thip nhit tuyet ddi khoang 15,0 - 16,0°C, vdi gia tri trung binh frong thang lanh nhit la 21,0 - 22,0»C.
Che do mua vd cdc yeu td khdc: Lugng mua trung binh nam d viing bien nay thap hon han so vdi vftng biSn nam vinh Bac Bg, viing bien tft Quang Tri den Quang Ngai va tuong duong vdi viing bien bic vjnh BSc Bp. Gia frj phd biin cua lugng mua nam frong khoang 1200 - 1900mm. Mfta mua lui mudn hon so vdi cac vung bien phia bac, thdi gian keo dai cua mfta mua cung ngin hon, tu thang IX den thang XII, frong dd mua nhieu nhat vao 3 thang IX, X, XI, Trong nam cd khoang 3 - 4 thang cd lugng mua dudi 50 mm/thang. Gia tri phd bien ciia dp am tuong ddi trung binh nam la 75-80%, lugng boc hoi nam la 1100 - 1900mm, Idn hon han so vdi cac vung biin phia bac. Chi sd am udt nam dao ddng frong khoang 1,0 - 1,7. Gia fri pho biin cau toe do gid frung binh nam la 2 - 3 m/s, toe do gid Idn nhat la 30- 40 m/s. Tdng sd gid ning frung binh nam d vung biin nay la 2500 - 2700 gid.
3.5. Ddc diem khi hgu vung bien tit Binh Thudn den Cd Mau
Che do nhiet: d viing bien nay nhiet dp phan bd tuong ddi ddng diu theo khdng gian va thdi gian, khdng cd sy khac nhau nhieu gifta nhiet dp mua ddng va nhiet do mfta he, vi thi bien do nam cua nhiet do d vung bien nay tuong ddi nhd. Nhiet do khdng khi trung binh nam dao ddng frong khoang 27,0 - 27,5''C.
Bien dd nam cua nhiet dp la 3,1 - 4,1 "C. Khdng gidng vdi cac vung bien phia bac, vung bien nay cd thang ndng nhat roi vao thang V, nhiet do khdng khi tdi cao tnmg binh frong thang nay la khoang 32°C. Nhiet dp khdnp khi tdi thap tnmg binh frong thang lanh nhat (thang I)la23,5-24,0»C.
Che do mua vd cdc yeu td khdc: Lupng mua trung binh nam dao ddng trong mdt khoang kha rdng vdi trj sd phd biin la 1250 - 2100 mm. Mfta mua keo dai tft thang V din thang XI, mua nhieu nhit vao 3 thang VIII, IX, X. Dp am tucmg ddi trung bmh nam la 80 - 85%, lugng bdc hoi nam la 1100 - 1300mm, chi sd am udt nam la 1,0 - 1,8. Toe dd gid trung binh nam phd bien la 2,5 - 5,5 m/s, tdc do gid manh nhat la 30 - 50 m/s.
3.6. Dgc diem khi hdu viing bien tie Cd Mau den Kien Giang
Che do nhiet: Gia tri nhiet do tnmg binh nam d vftng bien nay cung tuong duong nhu cac vftng biin khu vyc Trung Bd vdi gia tri vao khoang 27,2°C va khdng cdn miia ddng lanh. Bien do nam cua nhiet do tuong ddi
^^\ Sothang 8+9nam2014
•H NGHIEN CUU - TRAO DOI
nhd. Thang ndng nhit la cac thang IV va V, vdi nhiet dp tnmg binh thang la 28,5°C va thang lanh la thang I, vdi nhiet do trung binh thang la 25,7°C. Nhiet dp cao nhat tuyet ddi la 37,0°C, nhiet dp thip nhat friyet ddi la I6,0''C.
Che do mua vd cdc yeu td khdc: Lugng mua trung binh nam d vung bien nay Idn hon han so vdi cac vung bien phia bac, khoang 2500 - 3000mm. Vi mua mua d day den sdm hon, bat dau tft thang IV va keo dai den thang XI, mua nhiiu nhit vao 3 thang VII, VIH, DC.
Trong mua mua cd 4 - 5 thing mua fren 300 mm va khoang 2 - 3 thang frong thdi ky it mua cd mua dudi 50mm. Tri sd phd bien cua dp am tuong ddi trung bmh nam la 80 - 85%, lugng bdc hoi nam la 1200 - 1300m, chi sd am udt nam la 2,0 - 2,5. Tdc do gid trung binh nam la 2,5 - 3,0 m/s, tdc do gid eye dai nam vao khoang 40 m/s. Sd gid nang trung bmh nam khoang la 2300 - 2400 gid frong dd cd 5 - 6 thang frong nam cd fren 200 gid nang.
3.7. Dgc diem khi hdu vung bien qudn ddo Hodng Sa (vdng bien ngodi khai bdc Bien Dong)
Che do nhiet: Nhiet do khu vuc quan dao Hoang Sa cd gia tri trung binh nam vao khoang 27,0°C va khdng cd mua ddng lanh du vi tri nam d khu vyc vT do tuong ddi cao.
Nhiet dp trung binh thang lanh nhat (thang I) van dat 23,0°C - 24,0°C, cao hem khu vuc dit Uin ciing vi dp tu 3,0 - 4,0°C. Nhiet dp trung bmh thang ndng nhat (thang V, VI) cung cM len tdi 29,2 - 29,3°C. Vl vay chenh lech nhiet
dp giiia mua ddng va mua he d vftng bien nay nhd hon dang ke so vdi dat liin. Chenh lech nhiet dp gifta thang ndng nhat va thang lanh nhat frong nam la vao khoang 6,0°C, nhd hon so vdi tten dat lien. Nhiet do tdi cao tuyet ddi khdng vugt qua 36,0°C va nhiet do tdi thap tuyet ddi khdng xudng dudi 17,0°C.
Che do mua vd cdc yeu td khdc: Che dp mua d viing bien nay gin Hen vdi hoat dpng cua gid mfta. Mfta mua trung vdi mua gid mua mfta ha va mfta it mua trung vdi mua gid mua mfta ddng. Mua it mua keo dai tft thang XII den thang V vdi lugng mua trung binh ttong cac thang it mua nhat (thang I, II, III) vao khoang 15-30 mm va sd ngay mua tft 5 - 8 ngay; cac thang cdn lai cd lugng mua trung binh vao khoang 30 - 70mm. Mua mua bat dau tu thang VI den thang XI vdi Iugn| mua thang tft 110 - 250mm, mua nhieu nhat vao cac thang VIII, DC, X. Sd ngay mua ttong cac thang mfta mua tft 7 - 14 ngay. Sd ngay mua trong nam khoang 110 ngay. Day la vftng bien it xay ra trudng hgp mua Idn, tdng lugng mua trung binh nam chi khoang 1100 - 1300 mm, thap hon tat ca cac vimg bien ven bd khac. Do am khdng khi cao quanh nam, trung binh vao khoang 82 - 85%, thap nhit ciing dat gia tri 81%.
Hudng gid ttong timg mua rat dn djnh.
Mfta ddng gid thjnh hanh hudng Ddng Bac vdi tan suat tten 50%i, hudng Bic vdi tin suat tten 25%. Mua he gid thjnh hinh hudng Nam vdi tan suit tren 50%, hudng Tay Nam vdi tin suit xap xi 30%. Mfta ddng gid manh hon.
hen
^..Xviex Nam
vdi toe do trung binh vio khoing 5 - 7m/s v i khoang 4 - 5m/s ttong mfta he. fl diy hiu nhu khdng quan ttic thiy Iang gid, tdc do gid nhd nhit cung dat gin 1,5 m/s nhung rit it.
3.8. Dgc diim khi hdu vimg bien qudn ddo Trucmg Sa (vitng bien ngodi khoi nam Bien Ddng)
Che do nhiet: Chi do nhiet vftng bieii quin dio Trudng Sa mang die diem cua che dp nhiet vung bien nhiet ddi xich dao, c6 nen nhiet do cao vi it bien ddi qua cic miia trong nam. Gia tti nhiet dp ttung binh nam vao khoing 27,0 - 28,0°C. Dang biin ttinh nam cua nhiet dp mang tinh chat xich dao, dd Ii biin trinh kep vdi bien do khi nhd. Bien do nam efta nhiet do khoing 3,0°C, eye dai chinh Ii vio thing ndng nhit Ii thing V vdi nhiet dp trung bmh thing la 29,2°C, cue dai phu Ii vao thing DC vdi gii tti la 28,5 - 29°C. Thing cd nhiet dp eye tieu la thing I, thing lanh nhat vdi nhiet dp trung binh thing khoing 26,0°C.
Nhiet do tdi cao trung binh nam Ii 29,7°C vi nhift do tdi thip trung binh nam chi thip hon vii do, cd tti sd Ii 26,1°C.
Che do mua vd cdc yeu td khdc: Lugng mua d viing bien quan dao Trudng Sa Idn gap khoang 2 lan so vdi vung bien quan dio Hoing Sa va cd su phan chia ro ret theo mfta, mua mua va mua it mua. Lugng mua trung binh nim khoing 2300 - 2500mm vdi hon 16 ngay mua/thing. Mua mua bat dau tu thing V ciing vdi sy bat dau cua hoat ddng gid mua mfta he vi ket thuc vio thing XII. Mua mua cung phan rd 2 thdi ky, mua nhieu vio diu vi cudi mfta, thing trung gian it mua la thing VIII.
Lugng mua trong cac thing mua nhieu nhit (X, XI, XII) cd gia tri trung bmh vao khoing 250 - 370 mm/thing vdi 20 ngiy mua/thing.
Trong thdi ky it mua, ttimg bmh mdi thing
lugng mua cung dat dugc fren 50mm vdi 7 - 16 ngiy mua/thang.
Do im tuong ddi trung binh nam d vftng bien quin dio Trudng Sa ciing cao tuong tu nhu ddi vdi vung bien quan dio Hoing Sa.
Do am quanh nam cao, chi xudng dudi 80%
vio thing IV v i thing V. Chi do gid vung biin quin dio Hoang Sa va Tnrdng Sa nhin chung Ii gidng nhau, gid thjnh hanh dn djnh theo mfta, tdc do gid Idn. Tdng lupng bdc hoi nam d vftng bien quan dio Trudng Sa dat gia ttj Idn nhit so vdi cac vftng bien khac. Lugng boc hoi trung binh nam phd biin tten khu vuc Biin Ddng dao dpng ttong khoing 700 -1300 mm ttong khi tai vung bien quan dio Trudng Sa dat khoing 1500mm.
Ket luin
Qua phin tich dac diem khi hau cua 8 vftng bien thudc Bien Ddng cd the nhan thiy diy la mien khi hiu mang ci net chung cua cac vung duyen hai lan can tten dat lien vi efta vftng khi hiu hai duong. 6 cac viing bien ven bd cd ehi do nhiet ciing nhu che do mua, im, che do gid, bdc hoi, ning,... ngoii nhung net CO ban cua vung khi hiu ven bd, cdn mang nhung net khi hiu hii duong. Viing khi hau hai duong dugc the hien rd ret qua dac diem khi hau vung bien quan dao Hoang Sa vi Trudng Sa, cd mua he mat hon vi mfta ddng am hon, nhiet do tdi cao thudng thip hon vi nhiet do tdi thip thudng cao hon so vdi khi hiu trong dat lien.
LM cam ofn: Bai bio hoan thinh nhd sy ttg giiip tft de tii cip Nhi nude "Nghien ciiu xay dung Atlas khi hiu va bien ddi khi hau Viet Nam" thudc Chuong ttinh KHCN- BDKH/11-15. •
