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1 WVRGPS 0

2 GPSWVR RAOBs ( Radiosonde Observation ) WVR GPS PW LWP GPSWVR RAOBs WVR GPS WVR

3 .....III.....IV WVR GPS GPS GPS WVR

4 PW LWP GPSWVR RAOBs

5 3-1WVR T b Tau Tb Tau WVR PW WVRGPS RAOBs WVRGPS RAOBs WVRGPS RAOBs Lamont

6 WVR A 3 B C D E F T s T m A 4 B C D E F T s T m A 5 B C D E F T s T m PW LWP PW LWP PW LWP WVR PW WVR PW WVR PW WVR 30 ()23.8 GHz ()31.4 GHz WVR 60 ()23.8 GHz ()31.4 GHz WVR 90 ()23.8 GHz ()31.4 GHz WVR ()30 ()60 () WVR 30 ()23.8 GHz ()31.4 GHz WVR 60 ()23.8 GHz ()31.4 GHz WVR 90 ()23.8 GHz ()31.4 GHz WVR ()30 ()60 () WVR 30 ()23.8 GHz ()31.4 GHz WVR 60 ()23.8 GHz ()31.4 GHz

7 WVR 90 ()23.8 GHz ()31.4 GHz WVR ()30 ()60 () : WVR PW LWP WVRGPS RAOBs WVRGPS RAOBs WVRGPS RAOBs RAOBs()WVR()GPS() (a) Total (b) Rainfall event ( > 0.1mm) (c) Rainfall event ( < 0.1mm) (d) maximum GPS()WVR()RAOBs() WVR-RAOBs()GPS-RAOBs()WVR-GPS() GPSWVR RAOBs (a)wvr-raobs (b)wvr-raobs (c)gps-raobs (d)gps-raobs (e)wvr-gps (f)wvr-gps WVR-RAOBsGPS-RAOBs WVR-GPS Lamont WVRGPS RAOBs (a)wvr-raobs (b)wvr-raobs (c)gps-raobs (d)gps-raobs (e)wvr-gps (f)wvr-gps Lamont WVR-RAOBsGPS-RAOBs WVR-GPS...64

8 ( Precipitable Water ; PW ) WVR (Global Position System ; GPS) ( ) GPS GPS Radiometrics Corporation ( WVR ) [7] [8][23][24][25]

9

10 2-1WVR Chandrasekhar ( 1960 ) I ν I ν 2-1 di ds ν = I κ ν e + S ( 2-1 ) S ( source function )κ e s

11 2-1 [20] Kirchoff κ a κ e S S a ν = κ B (T ) ( 2-2 ) B ν (T) Planck B ν 3 2 hν 1 ( T ) = 2 / kt c e h ν 1 ( 2-3 ) h Planck k Boltzmann c ν B ν (T) 2-2 B ν (T) = I ν

12 圖 2-2 表面亮度與輻射強度關係的示意圖[20] 綜合以上的推論 將(2-2)式帶入(2-1)式並求解(2-1)式 得到的 一般解 即為初步的輻射傳送方程式 I (0 ) = I ( s ) e ν ν τ ( s0 ) 0 + B (T ) e s0 ν 0 κ ds τ ( s) a ( 2-4 ) 其中 τ 為光程( optical depth ) τ ( r1, r 2 ) = r2 r1 κ a dr ( 2-5 ) 在(2-4)式中 s 0 為起始點的位置 等號右邊第一項表示大氣邊界層 的貢獻量 第二項為從邊界層到觀測位置之間路徑上的貢獻量 如 圖 2-3 圖 2-3 輻射傳遞路徑圖[20]

13 Rayleigh-Jeans hν << kt Planck 2 2ν kt 2kT B ν ( T ) = ( 2-6 ) 2 2 c λ λ (2-6) ( T )Planck ( B ν (T) ) ( Brightness TemperatureT b ) 2 λ T b ( ν ) I ν ( 2-7 ) 2k (2-4) T b ( ν ) τ ( s ) s T ( s ) 0 0 τ ( s ) = T ( ν ) e + e κ ds b 0 ( 2-8 ) 0 a R ( ν, T ( s )) T b0 (ν) R 2 1 / R( ν kt kt hν kt, T ) = ( e 1) 2 λ B ( T ) hν ( 2-9 ) ν R(ν,T) hν/kt

14 1 hν 1 hν R ( ν, T ) = 1 + [ ] + [ ] ( 2-10 ) 2! kt 3! kt Rayleigh-Jeans R = 1 (2-8) Radiative Transfer Equation RTE T b ( ν ) = τ ( s0 ) s0 T e + 0 T ( s) e b 0 τ ( s ) κ a ds ( 2-11 ) T b0 = 2.7 K 0 s T P ρ v κ a ( H 2 O ) ( O 2 ) κ + κ a =.15κ O κ 2 H 2O 1 ( 2-12 ) L Keihm [1992]

15 GHz( ) GHz( ) Liebe [1987] 50 GHz 70 GHz GHz [Rosenkranz 1975]

16 2-2GPS 2-2-1GPS GPS GPS [7] 2-2-2GPS GPS MHz (L1) MHz (L2) GPS i i i i i i L = ρ I + ρ + cδ cδ + λn 1k k k k k 1 ( 2-16 ) 1k f 2 i i 1 i i i i L ρ I + ρ + cδ cδ + λ n 2k k 2 k k k 2 2k = ( 2-17 ) f 2 L L1 L2 ρ I MHz δ k δ i

17 ( k ) ( i ) λ n GPS L1 2 f1 ρ = I ( 2-18 ) I 2 f 2 L = ( f L f ) ( 2-19 ) f f 3 L 1 2 [8] ij L 3kl i i j j = L L ) ( L L ) ( 2-20 ) ( 3k 3l 3k 3l [8] D Z m ( θ) + Z m ( θ) = ( 2-21 ) w w h h Z m ( Zenith Wet Delay ; ZWD )Z h ( Zenith Hydrostatic Delay ; ZHD )θ m w (θ)m h (θ)

18 ZWD ZHD ( Mapping Function ) Hopfield [17] 12 m w (θ) m h (θ) [13] ( k, l ) dd dd = Z m θ ) Z m( θ ) ( 2-22 ) k ( k l l Z k Z l ( k, l ) θ k θ i (2-22) dd = Z Z ) m( θ ) ( 2-23 ) ( k l l m(θ k )m(θ l ) [24]

19 3-1 Radiomatrics ( Water Vapor and Liquid Water RadiometerWVR ) WVR [25] 23.8 GHz 31.4 GHz 23.8 GHz ( GHz ) (pressure broadening) (down-link transmissions) ( Precipitable Water ) 31.4 GHz 3-1WVR-1100 [25]

20 3-2 [25] Instrument function or parameter Sample time functions Beam width Accuracy Resolution Radiometric range User selectable for all instrument 5.7 & 4.4 degree 0.3 K 0.25 K 0 K ~ 700 K Operating range -20C ~ +50C Power requirements condi- Voltage requirements Output Dimensions 120 watts maximum ( cold operating tions ) 3-1WVR [25] or vac, 50 to 440 Hz Rs-232 at 1200 baud, n, 8, 1, to notebook Computer, ASCII data files 50x28x76 cm

21 WVR 0 ( ) 180 ( [2] ( ) GPS WVR Raob GPS 3-3

22 WVR [15] (92 %94 % 98 %) 98 % [2] 98 % ( Tb )PW LWP [1] PW = A0 + A i Tb i i ( 3-1 ) LWP = B0 + B i Tb i i ( 3-2 ) A 0 B 0 A i B i i Tb τ PW LWP

23 PW = C 0 + τ i C i i ( 3-3 ) LWP = D 0 + τ i D i i ( 3-4 ) C 0 D 0 C i D i τ i (2-12) [20] ext T = T e τ + T (1 e τ b b mr ) ( 3-5 ) T mr (mean radiating temperature) [20] T mr = 0 0 α Te α e s 0 s α dt 0 α dt ds ds ( 3-6 ) (3-5) ext Tmr Tb τ ( db) = 3.43 ln ( 3-7 ) Tmr Tb [22]

24 WVR Tb WVR ( PW ) ( LWP ) ( T 0 ) ( Vd 0 ) ( P 0 ) [1] PW = LWP = A 0 B + A Tb + 0 i + B Tb i i i i i A i+ 1 + B T i T + 0 A i B Vd i+ 2 0 Vd A i + 3 B P i+ 3 0 P 0 ( 3-8 ) 2 WVR PW [1] X 0 j j ( j) = A + A Tb ( 3-9 ) i i i X(j) j ( ) A j 0 A j i (3-8)

25 3-3-2 GPS ZWD ZWD PW [23] PW = ZWD ( 3-10 ) 8 10 = ( 3-11 ) ρ R [( k / T ) k ' ] + v 3 m 2 R v (J/Kg-k)k ± (K 2 /mb) ρ k ±2.2 (K/mb)T m T m = ( P / T ) dz v 2 ( P / T ) dz v ( 3-12 ) P v (mb)t (K) % [10] [Liou et al. 2000b] GPS

26 T s [Bevis et al. 1992] [23] T a + b = ( 3-13 ) m T s a b 3-2 a b March April May

27 WVRGPS GPSWVR RAOBs 4-1 ( Temperature Inversion ) WVR GPS

28 ( T s ) ( T m ) T s T m T s T m R R 22.9 % R %

29 Month Raobs Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec March April May

30 A 3 B C D E F T s T m

31 A 4 B C D E F T s T m

32 A 5 B C D E F T s T m

33 4-2 PW LWP T b τpwlwp (3-1) (3-2)(3-3)(3-4) PW LWP PW LWP PW LWP T b PW LWP τ T b PW 4 11 LWP WVR PW LWP PW LWP

34 Month PW0 PW1 PW2 Mean Rmsd, cm Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month PW0 PW1 PW2 mean Rmsd,cm Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

35 Month LWP0 LWP1 LWP2 Mean Rmsd,µm Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month LWP0 LWP1 LWP2 mean Rmsd, µm Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

36 PW LWP

37 PW LWP

38 PW LWP

39 ( Tb ) 60 PW PW cm cm cm :00 ~ 24:

40 PW :00 ~ 14: :00 ~ 17: PW WVR WVR PW

41 30 PW mean(cm) 60 PW mean(cm) 90 PW mean(cm) 30 &60 30 &90 60 &90 March April May WVR PW

42 PW

43 PW

44 PW

45 WVR 30 ()23.8 GHz ()31.4 GHz LST = Local Standard Time

46 WVR 60 ()23.8 GHz ()31.4 GHz

47 WVR 90 ()23.8 GHz ()31.4 GHz

48 WVR ()30 ()60 ()90

49 WVR 30 ()23.8 GHz ()31.4 GHz

50 WVR 60 ()23.8 GHz ()31.4 GHz

51 WVR 90 ()23.8 GHz ()31.4 GHz

52 WVR ()30 ()60 ()90

53 WVR 30 ()23.8 GHz ()31.4 GHz

54 WVR 60 ()23.8 GHz ()31.4 GHz

55 WVR 90 ()23.8 GHz ()31.4 GHz

56 WVR ()30 ()60 ()90

57 [ ]

58 WVR PW LWP

59 GPSWVR GPS [2223] WVR ( Quality Control ; QC ) ( > 0.1 mm ) ( < 0.1 mm ) WVR PW GPS QC WVR GPS QC WVR 4-27 QC

60 PW 3 ~ 5 WVR GPS PW WVR GPS GPS WVR GPS 3 ~ 4 cm 4 ~ 5 cm 5 ~ 6 cm WVR GPS WVR - RAOBs GPS RAOBs WVR GPS PW RAOBs WVR GPS

61 4000 WVR GPS WVR - RAOBs GPS - RAOBs RAOBs PW RAOBs WVR - GPS WVR ~ 3 cm WVR GPS 4 cm PW WVR - GPS Lamont 4 ~

62 4-24 WVRGPS RAOBs

63 4-25 WVRGPS RAOBs

64 4-26 WVRGPS RAOBs

65 4-27RAOBs()WVR()GPS() (a) Total (b) Rainfall event ( > 0.1mm) (c) Rainfall event ( < 0.1mm) (d) maximum

66 WVR GPS RAOBs W-R G-R W-G Mean SD Mean SD Mean SD rmsd rmsd rmsd March April May WVRGPS RAOBs WVR GPS RAOBs W-R G-R W-G Mean SD Mean SD Mean SD rmsd rmsd rmsd March April May WVRGPS RAOBs WVR GPS RAOBs W-R G-R W-G Mean SD Mean SD Mean SD rmsd rmsd rmsd March April May WVRGPS RAOBs

67 4-28GPS()WVR()RAOBs()

68 4-29WVR-RAOBs()GPS-RAOBs()WVR-GPS()

69 WVR GPS RAOBs 0 ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ WVR-RAOBs GPS-RAOBs WVR-GPS -3 ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

70 GPSWVR (a)wvr-raobs (b)wvr-raobs (c)gps-raobs (d)gps-raobs (e)wvr-gps (f)wvr-gps 4-31WVR-RAOBsGPS-RAOBs WVR-GPS

71 4-32 Lamont WVRGPS RAOBs (a)wvr- RAOBs (b)wvr-raobs (c)gps-raobs (d)gps-raobs (e)wvr-gps (f)wvr-gps 4-33 Lamont WVR-RAOBsGPS-RAOBs WVR-GPS

72 WVR-RAOBs GPS-RAOBs WVR-GPS PW 0 ~ ~ ~ ~ ~ ~ ~ WVR-RAOBs GPS-RAOBs WVR-GPS PW 0 ~ ~ ~ ~ ~ ~ Lamont

73 WVR GPS(5 mm) RAOBs Total number ( no Q.C. ) Rainfall event ( > 0.1 mm) Rainfall event ( < 0.1 mm) Exclude Outliers ( Maximum ) After Q.C

74 1 WVR GPS 2 WVR PW WVR cm cm GPS RAOBs ( 4-29) 4 WVR WVR RAOBs 1.5 cm 1.0 cmwvr GPS 1.17 cm 0.88 cm

75 5 WVR GPS ( 0.37 cm ) WVR RAOBs GPS RAOBs ( cm ) WVR GPS RAOBs

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