I'm trying to plot some dots on a map in R but only half of them show up. I suppose it might have something to do with the dateline.
My sample data:
sites
longitude latitude
1 -136 53
2 140 33
3 -176 59
4 -138 47
5 -170 61
6 142 35
7 -128 45
8 -178 55
9 -140 57
10 -168 39
11 158 39
12 -178 45
13 144 45
14 -166 25
15 162 47
16 -178 35
17 -178 43
18 146 39
19 138 25
20 -178 25
21 140 33
22 166 45
23 142 37
24 164 45
25 -162 39
26 156 39
27 -178 53
28 -178 29
29 -150 59
30 -178 35
31 -176 57
32 138 43
33 164 59
34 -152 37
35 152 39
36 -178 61
37 164 35
38 174 51
39 -176 29
40 154 41
41 -140 51
42 120 35
43 -178 53
44 -168 55
45 -172 65
46 -126 59
47 -178 53
48 -144 45
49 -178 37
50 -122 59
51 -178 27
52 -176 43
53 128 27
54 -130 33
55 134 37
56 -156 55
57 -176 41
58 148 47
59 146 37
60 -164 37
61 158 35
62 124 47
63 162 63
64 -178 47
65 144 37
66 -170 25
67 120 41
68 -164 41
69 -178 45
70 140 47
71 164 45
72 -164 39
73 -178 41
74 120 35
75 -150 41
76 -154 45
77 124 43
78 148 39
79 -162 43
80 152 35
81 -138 39
82 124 29
83 -168 51
84 146 49
85 -178 35
86 -152 49
87 -162 43
88 160 53
89 152 35
90 126 31
91 -156 47
92 -174 33
93 164 41
94 160 37
95 -154 25
96 -178 41
97 142 49
98 -178 35
99 -178 51
100 138 35
101 -120 41
102 -160 47
103 148 37
104 166 41
105 -148 37
106 146 37
107 -168 53
108 -178 37
109 132 29
110 -122 57
The code:
wrld2 = st_as_sf(map('world2', plot=F, fill=T))
ggplot() +
geom_sf(data=wrld2, fill='lightgrey') +
geom_point(data=sites, aes(x = longitude, y = latitude), size = 4,
shape = 22, fill = "darkblue") +
coord_sf(xlim=c(-180,-120), ylim=c(25,65)) +
geom_sf(data=wrld2, fill='lightgrey') +
geom_point() +
geom_point(data=sites, aes(x = longitude, y = latitude), size = 4,
shape = 21, fill = "darkred") +
coord_sf(xlim=c(120,240), ylim=c(25,65)) +
theme(panel.background = element_rect(fill = "aliceblue"))
Only the Western part of the dateline is plotted with the correct dots (others are put on top):
The problem is that the blue data points are not plotted in their specific range (-180,-120 and 25,65) because of the two coordinate systems/dateline around +/- 180°. I can't seem to figure how to define the correct xlim so that the longitude ticks remain the same on the x-axis. Has anyone an idea what is missing or needs to be re-defined? Many thanks.
