The mrwater library is based on the STN river structure
(Vörösmarty et al. 2000, 2011) and the CRU gridded land mask (Harris et
al. 2014, 2021).
The river structure is stored in the form of a sorted list of objects
in the folder inst/extdata and can be accessed with the
function call
rs <- readRDS(system.file("extdata/riverstructure_stn_coord.rds", package = "mrwater")).
For each of the 67420 grid cells, rs$nextcell contains the
cell that comes after the respective grid cell (i.e. cell to which
discharge of current cell flows (exactly 1 cell)). Values of -1 indicate
that there is no downstream cell (i.e. the respective cell is the last
of the river basin). rs$downstreamcells
(rs$upstreamcells) contains the list of downstreamcells
(upstreamcells) of the respective grid cell (i.e. all cells that are
downstream (upstream) of current cell (list of cells)). Values of 0
indicate that there is no downstream (upstream) cell.
rs$endcell provides the last downstream cell to the
respective cell (i.e. estuary cell of current cell, i.e. last cell of
the river of which current cell is part of (exactly 1 cell)). It
indicates which cells belong to one river basin.
rs$calcorder indicates the ordering of cells for
calculation from upstream to downstream. Grid cells with the same
calcorder can be calculated in parallel. rs$coordinates
provides the coordinates (lon.lat) to the respective grid cell.
rs <- readRDS(system.file("extdata/riverstructure_stn_coord.rds", package = "mrwater"))
str(rs)
#> List of 7
#> $ nextcell : num [1:67420] -1 -1 -1 13 6 14 15 9 -1 -1 ...
#> $ downstreamcells:List of 67420
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num [1:4(1d)] 13 26 38 39
#> ..$ : num [1:5(1d)] 6 14 26 38 39
#> ..$ : num [1:4(1d)] 14 26 38 39
#> ..$ : num [1:4(1d)] 15 27 38 39
#> ..$ : num 9
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 10
#> ..$ : num(0)
#> ..$ : num [1:3(1d)] 26 38 39
#> ..$ : num [1:3(1d)] 26 38 39
#> ..$ : num [1:3(1d)] 27 38 39
#> ..$ : num [1:3(1d)] 28 38 39
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num [1:2(1d)] 31 30
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num [1:3(1d)] 26 38 39
#> ..$ : num [1:2(1d)] 38 39
#> ..$ : num [1:2(1d)] 38 39
#> ..$ : num [1:2(1d)] 38 39
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 30
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 33
#> ..$ : num 24
#> ..$ : num [1:3(1d)] 26 38 39
#> ..$ : num [1:2(1d)] 38 39
#> ..$ : num 39
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 40
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num [1:2(1d)] 34 33
#> ..$ : num [1:2(1d)] 35 24
#> ..$ : num [1:3(1d)] 37 38 39
#> ..$ : num [1:2(1d)] 38 39
#> ..$ : num 39
#> ..$ : num(0)
#> ..$ : num [1:2(1d)] 41 40
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 54
#> ..$ : num [1:3(1d)] 45 34 33
#> ..$ : num [1:3(1d)] 58 67 76
#> ..$ : num [1:2(1d)] 67 76
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 64
#> ..$ : num [1:2(1d)] 67 76
#> ..$ : num 76
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 64
#> ..$ : num [1:2(1d)] 65 64
#> ..$ : num [1:2(1d)] 75 76
#> ..$ : num 76
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num [1:3(1d)] 88 89 90
#> ..$ : num [1:3(1d)] 88 89 90
#> ..$ : num [1:2(1d)] 89 90
#> ..$ : num 83
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 85
#> ..$ : num [1:3(1d)] 88 89 90
#> ..$ : num [1:2(1d)] 89 90
#> ..$ : num 90
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 93
#> ..$ : num [1:3(1d)] 96 97 98
#> ..$ : num [1:2(1d)] 97 98
#> ..$ : num 98
#> ..$ : num(0)
#> ..$ : num(0)
#> .. [list output truncated]
#> $ upstreamcells :List of 67420
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 5
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 8
#> ..$ : num 11
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 4
#> ..$ : num [1:2] 5 6
#> ..$ : num 7
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num [1:2] 35 46
#> ..$ : num(0)
#> ..$ : num [1:7] 4 5 6 13 14 25 36
#> ..$ : num [1:2] 7 15
#> ..$ : num 16
#> ..$ : num(0)
#> ..$ : num [1:2] 19 31
#> ..$ : num 19
#> ..$ : num(0)
#> ..$ : num [1:3] 34 45 56
#> ..$ : num [1:2] 45 56
#> ..$ : num 46
#> ..$ : num(0)
#> ..$ : num 47
#> ..$ : num [1:16] 4 5 6 7 13 14 15 16 25 26 ...
#> ..$ : num [1:18] 4 5 6 7 13 14 15 16 25 26 ...
#> ..$ : num [1:2] 41 51
#> ..$ : num 51
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 56
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 55
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 57
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num [1:3] 65 72 73
#> ..$ : num 73
#> ..$ : num(0)
#> ..$ : num [1:3] 57 58 66
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 74
#> ..$ : num [1:6] 57 58 66 67 74 75
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 82
#> ..$ : num(0)
#> ..$ : num 86
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num [1:3] 79 80 87
#> ..$ : num [1:5] 79 80 81 87 88
#> ..$ : num [1:6] 79 80 81 87 88 89
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 94
#> ..$ : num(0)
#> ..$ : num(0)
#> ..$ : num 95
#> ..$ : num [1:2] 95 96
#> ..$ : num [1:9] 95 96 97 104 105 106 107 116 117
#> ..$ : num(0)
#> .. [list output truncated]
#> $ endcell : num [1:67420(1d)] 1 2 3 39 39 39 39 9 9 10 ...
#> $ calcorder : num [1:67420(1d)] 1 1 1 2 1 2 2 1 2 2 ...
#> $ cells : chr [1:67420] "FJI.1" "RUS.2" "RUS.3" "RUS.4" ...
#> $ coordinates : chr [1:67420] "-179p75.-16p25" "-179p75.65p25" "-179p75.65p75" "-179p75.66p25" ...While rs$endcell can be used to uniquely identify which
grid cells belong to one common basin, it does not provide the name of
the river basin. To identify specific river basins, the
toolSelectRiverBasin function can be used to select all
grid cells that belong to one specific river basin that is listed in the
RiverBasinMapping.csv stored in inst/extdata.
It returns a list of grid cells including their coordinates and country
attribution.