Rec. ITU-R PN.837-1

1

RECOMMENDATION ITU-R PN.837-1

CHARACTERISTICS OF PRECIPITATION FOR PROPAGATION MODELLING

(Question ITU-R 201/3)

(1992-1994)

Rec. ITU-R PN.837-1

The ITU Radiocommunication Assembly,

considering

a)

that information on the statistics of precipitation intensity is needed for the prediction of attenuation and

scattering caused by precipitation;

b)

that the information is needed for all locations on the globe;

c)

that a digitized version of the rainfall climate zone maps has been prepared that may be valuable in some

computer applications,

recommends

1.

that Figs. 1 to 3 be used to select the rain climate region for the prediction of precipitation effects;

2.

that Table 1 be used to obtain the expected median cumulative distribution of rain rate for the rain climate

region;

3.

that when the rain climate zone is required in computer applications for any given set of geographic

coordinates, the program RAINZONE be used. (The software for RAINZONE may be obtained from the ITU
Radiocommunication Bureau.)

TABLE 1

Rain climatic zones

Rainfall intensity exceeded (mm/h) (Reference to Figs. 1 to 3)

Percentage

of time

(%)

A

B

C

D

E

F

G

H

J

K

L

M

N

P

Q

1.0

01

<

0.1

2

0.5

2

0.7

1

2.1

1

0.6

0

1.7

1

3

1

2

1

8

10

1.5

10

2

11

4

11

5

1

12

1

24

0.3

01

<

0.8

2

2

.

2

2.8

1

4.5

1

2.4

0

4.5

1

7

1

4

13

10

4.2

10

7

1

11

1

15

1

34

1

49

0.1

01

<

2

.8

2

3

.5

2

5

.5

1

8

.5

1

6

.5

0

8

.5

12

10

20

0

12

.5

1

15

1

22

1

35

1

65

1

72

0.03

1

<

5

.8

2

6

.5

2

9

.5

13

.5

12

.5

15

.5

20

18

28

0

23

.5

1

33

1

40

1

65

105

1

96

0.01

1

<

8

.8

12

.5

15

.5

19

.5

22

.

28

.

30

32

35

0

42

.

1

60

1

63

1

95

145

115

0.003

14

.8

21

.

26

.

29

.

41

5

54

5

45

55

45

0

70

.

105

1

95

140

200

142

0.001

22

.8

32

.

42

5

42

5

70

5

78

5

65

83

55

100

5

150

120

180

250

170

2

Rec. ITU-R PN.837-1

D01-sc

FIGURE 1/PN.837...[D01] = 3 CM PLEINE PAGE

Rec. ITU-R PN.837-1

3

D02-sc

FIGURE 2/PN.837...[D02] = 3 CM PLEINE PAGE

4 Rec. ITU-R PN.837-1

D03-sc

FIGURE 3/PN.837...[D03] = 3 CM PLEINE PAGE

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