Geoscience Reference
In-Depth Information
coecient of the second mode are 1.26, 0.13,
−
0.9 and
−
0.04, respectively.
This time coecient indicate that the intensity of EASM is stronger and
stay at North China and Northeast China longer prior to 1965, but EASM
stayed at Yangtze River shorter. This situation changed greatly at 1965,
especially after 1980, the mean time coecient is
0.9 during the period
of 1980-1993, and in this period EASM stayed longer and was stronger in
south of Yangtze River while the time it stayed was shorter in North China.
However, the situation changed again in 1994.
−
4. The Variability of EASM and the Spatial Distribution
of Rainfall in East China
From Sec. 3, we know that the EASM's movement exhibits interdecadal
abrupt shift in 1965, 1980, and 1994. We divided the EASM movement into
four stages from 1958 to 2001 based on the time coecient changes of the
second eigenvector and give out the mean process of EASM's movement in
each stage (Fig. 5).
1958-
1
964
1965-
1
979
50
50
(a)
(b)
41
42
42
45
45
39
37
41
43
40
40
38
44
43
40
40
39
44
46
45
3
38
35
35
36
36
45
35
30
35
30
34
34
33
32
33
32
30
31
25
31
25
28
30
28
20
29
20
15
15
10
10
100
105
110
115
120
125
130
135
140
100
105
110
115
120
125
130
135
140
1
9
94-2001
1980-1993
55
50
(c)
(d)
50
45
41
41
4
43
40
45
42
4
44
40
40
40
39
39
35
38
38
36
37
45
45
44
35
37
36
46
33
35
35
30
34
31
32
32
30
30
33 34
31
29
25
28
30
25
27
28
20
20
15
15
10
10
95
100
105
110
115
120
125
130
135
140
100
105
110
115
120
125
130
135
140
Fig. 5. The mean fronts of EASM for (a) 1958-1964, (b) 1965-1979, (c) 1980-1993, and
(d) 1994-2001.
