Luong mua d Tay Nguyen phan bo khdng deu ea theo khdng gian va thdi gian. Nhin chung, luong mua tang theo dp eao, song dp cao dat lUOng mUa cUc dai chi vao khoang 1000 ^
1500m. Ndi cd lupng mUa nam Idn thudng la sudn tay nam cua cac day nui - sudn ddn gid mua tay nam, cdn ndi cd lUOng mUa nho thudng la cac vung triing hoac cae thung lung khuat gid.
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Lupng mUa trung binh nam d viing tay nam eao nguyen Bao Lpc len tdi 3200 -^ 3500mm trong khi d viing triing Cheo Reo-Phii Tuc chi tren dudi 1200mm.
Bien trinh nam cua lupng mua d Tay Nguyen cd hai dang chinh, dang ddn nhU d Play Cu, Budn Me Thupt, Bao Lpc v.v... va loai kep nhu d Khanh DUdng, An Khe, Cheo Reo v.v.... LuOng mua cac thang mua mUa d hau het cac viing thude Tay Nguyen deu chiem ty trpng Idn, tren 75% tong lupng mUa nam. nhieu ndi len tdi 85 -^ 90% nhu d Budn Me Thupt, 90 v 95% nhu d Play Cu.
Do phan Idn lanh tho Tay Nguyen nam d phia tay TrUdng Sdn nen mua mUa thudng bat dau vao thang V va ket thiic vao thang X triing vdi thdi ki gid miia miia ha- Thang cd lupng mUa eye dai thudng rdi vao thang VII (Bao Lpc) hoac thang VIII
(Budn Me Thupt, Play Cu). Mpt sd ^/iing d phia ddng nhu An Khe, Khanh Duong, miia mua cd the keo dai den thang XI, tham chi den thang XII. Trong miia khd lupng mua chiem mdt ty le rat nho, lupng mUa thang it mUa nhat chi tren dudi 10mm, cd ndi dudi 1mm, dieu dd cd nghla la cd nhiing nam khdng ed mua ngay nao trong thang nay.
So ngay mUa trong nam tap trung chu yeu vao cac thang miia mUa cdn trong miia khd, nhieu khi cd thdi ki dai khdng mUa. Luong mUa ciing nhu sd ngay mUa, . mua mUa cd bien ddng Idn til nam nay qua nam khac. Luong mua nam nay cd the Idn
ft
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muon ciing gay khdng i t khd khan cho s a n x u a t ndng n g h i e p .
5. Che Tin ^m v^ hoc hAi.
Dp am tUdng ddi thudng tang theo dp cao dia hinh, vi vay d viing niii cao gia tri trung binh nam cua nd cd the dat tdi 85 ^ 90% trong khi d viing binh nguyen chi nam trong khoang 75 ^ 80%. Bien trinh nam eua dp am kha phii hpp vdi bien trinh nam cua lupng mua, nghla la dp am cao xuat hien vao miia mUa cdn dp am thap xuat hien vao mua khd. Bien dp nam cua dp am tUdng ddi kha Idn, dat tdi 15 -^ 20%. Dp am thap nhat tuyet ddi trong nam ed the xudng dudi 20% d cac tinh phia bae va dudi 10% d Lam Dong. Khoang gan mpt nUa sd ngay trong cac thang khd nhat (II, III, IV) cd do am thap nhat hang ngay nam trong khoang 35 v 50% va cd khoang 5 ^ 20% sd ngay dp am thap nhat hang ngay xuong dudi 30% [18].
Lupng bde hdi kha nang d Tay Nguyen dao ddng trong khoang 600 v 1500mm/nam. Ndi cd lUOng bde hdi kha nang Idn la Budn Me Thupt vdi gia tri trung binh nam: 1600mm, gap ba lan gia tri ndi cd lupng bde hdi it nhat [^6]. Lupng boc hdi kha nang dat gia tri eye dai vao thdi ki mua khd, liic dd ham lupng hdi nUdc trong khdng khi nho va toe dp gid Idn. Thang III thudng la thang cd lUOng boc hdi kha nang Idn nhat vdi gia tri 230mm/thang d Budn Me Thupt, 170 -r ISOmm/thang d Play Cu, Lien KhUdng. Lupng boc hdi ngay Idn nhat vao khoang tren dudi 10mm, gia tri cao nhat quan trac duoc d Budn Me
- 49 -Thupt l a 14,1mm [ 1 8 ] .