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Maun's Most Discussed Topic
Maun is now over 800mm of rain since November!
The
'annual flood' takes up to 6 months to flow from the Angolan Highlands
- the Mohembo flow rates give us the best indication of what is coming
to Maun. The Okavango Delta is very flat and the flood seldom goes in
the some direction thru the lower Delta. Sometimes it goes north around
Chief's Island, sometimes it flows into Lake Ngami sometimes...
Because of heavy rain this year we are
also getting a 'local flood.' Large areas off the Delta are having a
local flood - causing water to run and lifting water levels in the
channels. Local water will be waiting for the annual flood to arrive.
The surprise this week is the flow rate has dropped. A possible reason
is that the river is already overflowing the banks at Mohembo, making
the channel much wider than usual.There is speculation of heavy
flooding to come.
Speculation has proved to be too optimistic. Our April 10th chart below
shows flow rates of 400 cubic metres per second - a good historic rate,
not great. With signs that the rainy season is over, expectations are
now that we have just about peaked. The next 1-2 charts will tell the
story. The April 20th chart is encouraging, with cubes per second over
400. What we are getting is a 'late peak.' If the peak gets into the
500-600 range it will be the 4th highest peak in recent times and will
keep the Thamalakane River in Maun flowing for at least another 6
months. Have a look at the May 20th chart! Mohembo is just peaking - moving into record territory for this late in the year. The water will flow through Maun - late, long and hard. A research boat trip last weekend on at Gamoti River showed plenty of water is coming towards Maun. Sometimes this river doesn't flow for a decade - or more. What will the next chart show?
Strangest flood in years. While the peak did not reach great hights, the breadth has been very good. For so late in the flood season we are in record territory - never so high so late. Water will run in the Thamalakane River for the next 8-10 months. Water levels are already rising in Maun because of the rains in Angola.
Monthly Rainfall - Maun(mm)
Year
|
|
Jan
|
Feb
|
Mar
|
Apr
|
May |
June |
July |
Aug |
Sept |
Oct |
Nov |
Dec |
Totals |
10 Year Ave |
| 1923 |
|
120.4 |
118 |
95.4 |
8.9 |
12 |
0 |
0 |
0 |
0 |
24.2 |
24.2 |
94.6 |
497.8 |
|
| 1924 |
|
14.4 |
47.4 |
189 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
26.1 |
35.6 |
313.2 |
|
| 1925 |
|
62.6 |
27.7 |
78.6 |
14 |
9.2 |
0 |
0 |
0 |
14 |
1.3 |
9.6 |
83.1 |
299.8 |
|
| 1926 |
|
38.4 |
41.5 |
10.7 |
17.8 |
0 |
0 |
0.5 |
0 |
0.5 |
16.8 |
38.8 |
102 |
267.1 |
|
| 1928 |
|
161.6 |
39.5 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
67.3 |
3.3 |
102 |
373.8 |
|
| 1929 |
|
113 |
53.8 |
14.2 |
0 |
0 |
0 |
0 |
0 |
0.6 |
4.3 |
71.9 |
87.2 |
345 |
|
| 1930 |
|
47.5 |
66.3 |
9.5 |
90.9 |
0 |
0 |
0 |
0 |
1.3 |
0.8 |
22.8 |
108 |
347.5 |
349.2 |
| 1931 |
|
88.8 |
103 |
84.1 |
35.8 |
0 |
0 |
0 |
0 |
0 |
1.8 |
12.7 |
107 |
432.9 |
|
| 1932 |
|
25.4 |
174 |
274 |
14 |
0 |
0 |
0 |
0 |
0 |
11.4 |
46.5 |
41.8 |
587.1 |
|
| 1933 |
|
89.7 |
20 |
15.3 |
0 |
0 |
0 |
0 |
0 |
0 |
2.9 |
13.7 |
51.4 |
193 |
|
| 1934 |
|
122.7 |
111 |
44.9 |
47.7 |
2.6 |
0 |
0 |
0 |
0 |
0 |
116 |
56.7 |
500.7 |
|
| 1935 |
|
73.8 |
56.6 |
16 |
13.2 |
0 |
0 |
0 |
0 |
0 |
3.3 |
56.9 |
49.4 |
269.2 |
|
| 1936 |
|
106.9 |
47.5 |
270 |
28.9 |
34 |
0 |
0 |
0 |
0 |
4.3 |
57.3 |
63.6 |
612 |
|
| 1937 |
|
60 |
169 |
39.1 |
9.5 |
0 |
0 |
0 |
0 |
0 |
2.8 |
14.8 |
84.4 |
380 |
|
| 1938 |
|
138.8 |
46 |
19.6 |
48.3 |
0 |
0 |
0 |
0 |
0 |
0.3 |
16.8 |
44.1 |
313.9 |
|
| 1939 |
|
62.4 |
216 |
43.1 |
0.5 |
0 |
1 |
0 |
0 |
0 |
33 |
115 |
100 |
571.1 |
|
| 1940 |
|
69.2 |
56.5 |
153 |
90.9 |
0 |
0 |
0 |
0 |
10 |
22.1 |
36.2 |
101 |
539.6 |
439.9 |
| 1941 |
|
151.1 |
59.9 |
0 |
10.2 |
0 |
0 |
0 |
0 |
4.3 |
10.9 |
14.5 |
44 |
294.9 |
|
| 1942 |
|
31.5 |
71.6 |
121 |
9.8 |
14 |
0 |
0 |
0 |
0 |
40.6 |
36 |
56.9 |
380.8 |
|
| 1943 |
|
93.4 |
11.2 |
57.8 |
82.4 |
18 |
0 |
0 |
0 |
0 |
30.9 |
0.8 |
96.8 |
391.6 |
|
| 1944 |
|
145.8 |
319 |
15.8 |
6.9 |
0 |
3.3 |
0 |
0 |
0 |
5 |
23.9 |
72.3 |
591.7 |
|
| 1945 |
|
17.9 |
43 |
162 |
1 |
2 |
0 |
0 |
0 |
0 |
15.9 |
38.1 |
38.4 |
318.1 |
|
| 1946 |
|
395.9 |
95.3 |
0 |
0 |
3.8 |
0 |
0 |
0 |
0 |
15.1 |
48.2 |
81.4 |
639.7 |
|
| 1947 |
|
83.5 |
32 |
125 |
0 |
0 |
0 |
0 |
0 |
0 |
10.3 |
21.9 |
16.3 |
289.4 |
|
| 1948 |
|
110.9 |
175 |
172 |
67.9 |
0 |
0 |
0 |
0 |
0 |
1 |
92 |
102 |
720.5 |
|
| 1949 |
|
82.1 |
7.7 |
128 |
1.3 |
0 |
10 |
0 |
0 |
0.3 |
23.1 |
61.6 |
19.6 |
334.3 |
|
| 1950 |
|
106.9 |
119 |
40.4 |
38.3 |
23 |
0 |
0 |
0 |
0 |
5.1 |
61.6 |
133 |
526.7 |
448.8 |
| 1951 |
|
100.9 |
72.5 |
51.4 |
36.8 |
23 |
0 |
0 |
0.3 |
0 |
0 |
10.1 |
130 |
424.4 |
|
| 1952 |
|
91.5 |
108 |
10.3 |
0.3 |
10 |
0.3 |
0 |
0 |
0 |
61 |
70.4 |
88.6 |
441 |
|
| 1953 |
|
92.8 |
157 |
77.4 |
21.3 |
0.8 |
0 |
0 |
0 |
0 |
32.7 |
170 |
77.9 |
629.6 |
|
| 1954 |
|
142.1 |
96.7 |
86.9 |
16.1 |
0 |
0 |
0 |
0 |
0 |
4.8 |
77.1 |
137 |
560.5 |
|
| 1955 |
|
183.1 |
246 |
168 |
20.2 |
2.3 |
0 |
0 |
0 |
0 |
9.3 |
11.9 |
223 |
863.5 |
|
| 1956 |
|
54 |
129 |
53.3 |
25.6 |
2.8 |
0 |
0 |
0 |
0 |
32.2 |
48.1 |
82.3 |
427.4 |
|
| 1957 |
|
72.3 |
105 |
92.2 |
14.8 |
0 |
1.5 |
0 |
0 |
12 |
4.4 |
42.4 |
64 |
408 |
|
| 1958 |
|
230.9 |
125 |
88.6 |
3.1 |
0 |
0 |
0 |
0 |
2.1 |
29.4 |
27.5 |
95.9 |
602.4 |
|
| 1959 |
|
133.1 |
71 |
66 |
12.5 |
5.3 |
1.8 |
0.7 |
0 |
1.1 |
54.3 |
36.1 |
102 |
483.7 |
|
| 1960 |
|
30.5 |
73.4 |
21 |
71 |
16 |
3.3 |
0 |
0 |
0.1 |
2.1 |
18.3 |
80.2 |
316.1 |
515.7 |
| 1961 |
|
111.8 |
133 |
145 |
12.2 |
24 |
0 |
5.4 |
0 |
0 |
2.7 |
54.2 |
49.3 |
538.5 |
|
| 1962 |
|
155.1 |
35.5 |
8.3 |
41.2 |
0 |
0 |
0 |
3.9 |
0 |
3.8 |
30 |
35.9 |
313.7 |
|
| 1963 |
|
208.7 |
58 |
66.6 |
12.8 |
4.8 |
0.3 |
0 |
0 |
0 |
4.4 |
79.9 |
114 |
549.1 |
|
| 1964 |
|
79.2 |
70.1 |
17.6 |
0 |
0 |
0 |
0 |
0 |
0 |
29.8 |
98.9 |
209 |
504.3 |
|
| 1965 |
|
33.2 |
54 |
6.4 |
58 |
0 |
0 |
0 |
0 |
0.2 |
16.1 |
50 |
49.8 |
267.7 |
|
| 1966 |
|
101.1 |
160 |
124 |
59.7 |
0.2 |
17 |
0 |
0 |
2.3 |
0.2 |
35.6 |
52.5 |
552.3 |
|
| 1967 |
|
137.6 |
186 |
20.8 |
120 |
0 |
0 |
0 |
0 |
29 |
0 |
2.7 |
108 |
605.1 |
|
| 1968 |
|
109.9 |
104 |
81.3 |
65.5 |
34 |
0 |
0 |
0 |
0 |
8.8 |
112 |
64.1 |
579.5 |
|
| 1969 |
|
50.2 |
245 |
36.9 |
15.4 |
0.1 |
0 |
0 |
9.6 |
0 |
2.1 |
70.2 |
59.9 |
489.7 |
|
| 1970 |
|
123.6 |
21.2 |
9.2 |
1.4 |
0 |
0 |
0 |
0 |
21 |
10.1 |
67.6 |
13 |
267.1 |
466.7 |
| 1971 |
|
108.4 |
12.4 |
34.4 |
44.6 |
0 |
0 |
0 |
0 |
8.6 |
0 |
58.7 |
160 |
426.8 |
|
| 1972 |
|
260.3 |
51.5 |
193 |
19.8 |
0 |
0 |
0 |
0 |
1.6 |
9.7 |
66.8 |
94.4 |
697 |
|
| 1973 |
|
80.8 |
67.5 |
21.9 |
14.8 |
0 |
0 |
0 |
0 |
0 |
10.5 |
2 |
45.2 |
242.7 |
|
| 1974 |
|
347 |
366 |
17.9 |
50.1 |
0 |
0 |
0 |
0 |
0 |
101 |
43.9 |
262 |
1187.6 |
|
| 1975 |
|
161.1 |
60.8 |
191 |
71.3 |
3.5 |
0 |
0 |
0 |
11 |
6.5 |
98.7 |
27.8 |
632.2 |
|
| 1976 |
|
113.6 |
68.1 |
108 |
3.7 |
2.7 |
0 |
0 |
0 |
0 |
1.2 |
10.5 |
71.2 |
379.3 |
|
| 1977 |
|
114.8 |
98.4 |
127 |
19.2 |
4 |
0 |
0 |
1.2 |
12 |
25.3 |
74.2 |
37.7 |
513.3 |
|
| 1978 |
|
91.9 |
226 |
37.4 |
12.1 |
14 |
12 |
0 |
0 |
32 |
3.1 |
77.1 |
227 |
732.8 |
|
| 1979 |
|
124.8 |
30.2 |
25.8 |
7.3 |
0 |
0 |
0 |
0.1 |
0.2 |
11.2 |
19 |
73.2 |
291.8 |
|
| 1980 |
|
91 |
291 |
42.5 |
1.2 |
0 |
0 |
0 |
0 |
0 |
26.8 |
20.1 |
36.5 |
508.6 |
561.2 |
| 1981 |
|
126.3 |
161 |
92.9 |
5.2 |
4.5 |
0 |
0 |
0 |
1.9 |
3 |
74 |
27.7 |
496.1 |
|
| 1982 |
|
24.5 |
17 |
11.3 |
14.9 |
0 |
0 |
0 |
0 |
0 |
8.2 |
74.7 |
58.6 |
209.2 |
|
| 1983 |
|
98.6 |
11.4 |
25.1 |
19.5 |
16 |
1 |
0 |
0 |
0 |
101 |
84.2 |
34.6 |
391.3 |
|
| 1984 |
|
20 |
17.9 |
81.8 |
8.3 |
0.9 |
0 |
0 |
0.3 |
0 |
20 |
53.5 |
153 |
356.1 |
|
| 1985 |
|
76.8 |
41.8 |
55.1 |
2.4 |
0 |
0 |
0 |
0 |
0.5 |
20.2 |
92.5 |
12.6 |
301.9 |
|
| 1986 |
|
53.8 |
70 |
34.6 |
52.4 |
11 |
0 |
0 |
0 |
0 |
21.6 |
7.8 |
135 |
385.6 |
|
| 1987 |
|
32.2 |
60.3 |
27.3 |
0 |
0 |
0 |
0 |
0 |
19 |
49.6 |
49.3 |
57.1 |
295 |
|
| 1988 |
|
38.2 |
104 |
79.4 |
19.2 |
0 |
0 |
0 |
0 |
3.9 |
8.5 |
6.1 |
92.3 |
351.6 |
|
| 1989 |
|
215.5 |
180 |
44.3 |
96.3 |
0 |
0 |
0 |
0 |
7.6 |
12.9 |
14.5 |
46 |
617.3 |
|
| 1990 |
|
87.1 |
110 |
33.3 |
17.3 |
0 |
0 |
0 |
0 |
0 |
17.4 |
5.5 |
41.5 |
312.2 |
371.6 |
| 1991 |
|
177.6 |
134 |
123 |
0 |
0 |
0 |
0 |
0 |
5.8 |
28.5 |
13.3 |
78.4 |
560.2 |
|
| 1992 |
|
50.1 |
7.4 |
87.9 |
5 |
0 |
0 |
0 |
0 |
1.4 |
6.7 |
40.7 |
55.1 |
254.3 |
|
| 1993 |
|
66.5 |
122 |
15.4 |
47.4 |
0 |
0 |
0.7 |
0 |
8.2 |
14.3 |
23.9 |
155 |
453.2 |
|
| 1994 |
|
275 |
50 |
6.2 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
44 |
15.2 |
390.4 |
|
| 1995 |
|
27 |
14.4 |
0 |
2 |
0 |
0 |
0 |
22 |
11 |
16.6 |
54.1 |
|
146.9 |
|
| 1996 |
|
189.3 |
281 |
9 |
0.4 |
2.9 |
0 |
0 |
0 |
0.5 |
3.5 |
105 |
46.1 |
637 |
|
| 1997 |
|
153.8 |
19.2 |
64.8 |
1.8 |
5.1 |
0 |
0 |
0 |
13 |
26.6 |
24.8 |
67.8 |
376.5 |
|
| 1998 |
|
150.2 |
18.6 |
28.4 |
32.6 |
0 |
0 |
0 |
0 |
0 |
1.7 |
50.5 |
109 |
391 |
|
| 1999 |
|
110 |
56.5 |
41.2 |
3.8 |
10 |
0 |
0 |
0 |
0 |
7.9 |
14.2 |
63.5 |
307.3 |
390. |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Ave. Monthly |
|
109.51 |
96.37 |
66.70 |
23.94 |
4.17 |
0.68 |
0.10 |
0.49 |
3.12 |
16.15 |
46.01 |
80.15 |
447.37 |
|
|
|
|
|
|
