Returns a projection that keeps Mongolia's shape and area true. Maps of the whole country look best in an equal-area Albers or Lambert conic projection centred on Mongolia; maps of Ulaanbaatar look best in UTM zone 48N.
Usage
mn_crs(type = c("albers", "lcc", "utm", "wgs84"))Arguments
- type
One of:
"albers": Albers equal-area conic centred on 104E, 47N, with standard parallels 43.5N and 50.5N. Best for national choropleths because areas are true."lcc": Lambert conformal conic with the same parameters. Keeps local shapes true."utm": UTM zone 48N (EPSG:32648), the usual choice for Ulaanbaatar and central Mongolia."wgs84": plain longitude and latitude (EPSG:4326).
Value
An sf::st_crs() object.
See also
Other mapping helpers:
mn_aimag_grid,
mn_label_points(),
mn_leaflet(),
mn_map(),
theme_mn()
Examples
mn_crs()
#> Coordinate Reference System:
#> User input: +proj=aea +lat_0=47 +lon_0=104 +lat_1=43.5 +lat_2=50.5 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs
#> wkt:
#> PROJCRS["unknown",
#> BASEGEOGCRS["unknown",
#> DATUM["World Geodetic System 1984",
#> ELLIPSOID["WGS 84",6378137,298.257223563,
#> LENGTHUNIT["metre",1]],
#> ID["EPSG",6326]],
#> PRIMEM["Greenwich",0,
#> ANGLEUNIT["degree",0.0174532925199433],
#> ID["EPSG",8901]]],
#> CONVERSION["unknown",
#> METHOD["Albers Equal Area",
#> ID["EPSG",9822]],
#> PARAMETER["Latitude of false origin",47,
#> ANGLEUNIT["degree",0.0174532925199433],
#> ID["EPSG",8821]],
#> PARAMETER["Longitude of false origin",104,
#> ANGLEUNIT["degree",0.0174532925199433],
#> ID["EPSG",8822]],
#> PARAMETER["Latitude of 1st standard parallel",43.5,
#> ANGLEUNIT["degree",0.0174532925199433],
#> ID["EPSG",8823]],
#> PARAMETER["Latitude of 2nd standard parallel",50.5,
#> ANGLEUNIT["degree",0.0174532925199433],
#> ID["EPSG",8824]],
#> PARAMETER["Easting at false origin",0,
#> LENGTHUNIT["metre",1],
#> ID["EPSG",8826]],
#> PARAMETER["Northing at false origin",0,
#> LENGTHUNIT["metre",1],
#> ID["EPSG",8827]]],
#> CS[Cartesian,2],
#> AXIS["(E)",east,
#> ORDER[1],
#> LENGTHUNIT["metre",1,
#> ID["EPSG",9001]]],
#> AXIS["(N)",north,
#> ORDER[2],
#> LENGTHUNIT["metre",1,
#> ID["EPSG",9001]]]]
sf::st_transform(mn_aimags(), mn_crs("albers"))
#> Simple feature collection with 22 features and 15 fields
#> Geometry type: MULTIPOLYGON
#> Dimension: XY
#> Bounding box: xmin: -1182877 ymin: -601751.4 xmax: 1207275 ymax: 584211.5
#> Projected CRS: +proj=aea +lat_0=47 +lon_0=104 +lat_1=43.5 +lat_2=50.5 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs
#> # A tibble: 22 × 16
#> pcode name name_en name_mn name_mns level type number iso_code nso_code
#> * <chr> <chr> <chr> <chr> <chr> <chr> <chr> <int> <chr> <chr>
#> 1 MN11 Ulaanbaa… Ulaanb… Улаанб… Ulaanba… aimag capi… NA MN-1 511
#> 2 MN21 Dornod Dornod Дорнод Dornod aimag aimag NA MN-061 421
#> 3 MN22 Sukhbaat… Sukhba… Сүхбаа… Sükhbaa… aimag aimag NA MN-051 422
#> 4 MN23 Khentii Khentii Хэнтий Khentii aimag aimag NA MN-039 423
#> 5 MN41 Tuv Tuv Төв Töv aimag aimag NA MN-047 341
#> 6 MN42 Govisumb… Govisu… Говьсү… Govisüm… aimag aimag NA MN-064 342
#> 7 MN43 Selenge Selenge Сэлэнгэ Selenge aimag aimag NA MN-049 343
#> 8 MN44 Dornogovi Dornog… Дорног… Dornogo… aimag aimag NA MN-063 344
#> 9 MN45 Darkhan-… Darkha… Дархан… Darkhan… aimag aimag NA MN-037 345
#> 10 MN46 Umnugovi Umnugo… Өмнөго… Ömnögovi aimag aimag NA MN-053 346
#> # ℹ 12 more rows
#> # ℹ 6 more variables: parent_pcode <chr>, region_pcode <chr>,
#> # aimag_pcode <chr>, soum_pcode <chr>, area_km2 <dbl>,
#> # geometry <MULTIPOLYGON [m]>