Create world map

[Chris6698]

Hi!

For a paper on paper publishing locations around the world, I need to create a map where those places are clearly indicated on the map. I would like it to be as pretty as possible since it's for a scientific publication.

So far I used "elevatr" package and I produced a nice topographic map. What I'm afraid with that one is that the focus is taken away from my subject: here's the code I used:

Version: Version 2023.03.1+446 (2023.03.1+446)

#libraries
libs <- c("elevatr", "terra", "tidyverse", 
          "sf", "giscoR", "marmap")

installed_libs <- libs %in% rownames(installed.packages())
if (any(installed_libs == F)) {
  install.packages(libs[!installed_libs])
}

invisible(lapply(libs, library, character.only = T))

#1. GET WORLD MAP

crsLONGLAT <- "+proj=longlat +datum=WGS84 +no_defs"

get_sf <- function() {
  world_sf <- giscoR::gisco_get_countries(
    year = "2016",
    epsg = "4326",
    resolution = "10"
  )
  
  world_transformed <- st_transform(world_sf, crs = crsLONGLAT)
  
  return(world_transformed)
}

world_transformed <- get_sf()

# 2. GET ELEVATION DATA

get_elevation_data <- function(world_elevation, world_elevation_df) {
  
  world_elevation <- get_elev_raster(
    locations = world_transformed, 
    z = 3, 
    clip = "locations") 
  
  world_elevation_df <- as.data.frame(world_elevation, xy = T) %>%
    na.omit()
  
  colnames(world_elevation_df)[3] <- "elevation"
  
  return(world_elevation_df)
}

world_elevation_df <- get_elevation_data()


# 3. MAP
library(marmap)
get_elevation_map <- function(world_map) {
  
  world_map <- ggplot() +
    geom_tile(data = world_elevation_df, 
              aes(x = x, y = y, fill = elevation)) +
    scale_fill_etopo() +
    coord_sf(crs = crsLONGLAT)+
    theme_minimal() +
    theme(text = element_text(family = "georg", color = "#22211d"),
          axis.line = element_blank(),
          axis.text.x = element_blank(),
          axis.text.y = element_blank(),
          axis.ticks = element_blank(),
          axis.title.x = element_blank(),
          axis.title.y = element_blank(),
          legend.position = "none",
          panel.grid.major = element_line(color = "white", size = 0.2),
          panel.grid.minor = element_blank(),
          plot.title = element_text(size=18, color="grey20", hjust=1, vjust=-5),
          plot.caption = element_text(size=8, color="grey70", hjust=.15, vjust=20),
          plot.margin = unit(c(t=0, r=0, b=0, l=0),"lines"), #added these narrower margins to enlarge maps
          plot.background = element_rect(fill = "white", color = NA), 
          panel.background = element_rect(fill = "white", color = NA),
          panel.border = element_blank()) +
    labs(x = "", 
         y = NULL, 
         title = "Topographic map world", 
         subtitle = "", 
         caption = "CRD")
  
  return(world_map)
}

world_map <- get_elevation_map()
#world_map
ggsave(filename="world_topo_map.png", width=7, height=8.5, dpi = 600, device='png', world_map)

I also used a simple map using ggplot. Here's the code I used:
world_coordinates <- map_data("world")

ggplot() + geom_map(
    data = world_coordinates, map = world_coordinates,
    aes(x = x, y = y, map_id = region),
    color = "white", fill = "lightgray", size = 0.1  ) + 
geom_point(
    data = duse_cut,
    aes(x, y, fill="#e672f4"), # dark blue
    alpha = 0.7) +
    theme_bw() + 
    theme(legend.position="none")

Any suggestion on a world map that I could use?

[moniqa]

I do not have any tips for you about using R Studio to create map but the idea is to create a map exactly in R Studio? Or this is the software you usually to create maps? I am asking because free software QGIS is quite nice to prepare the maps, even for scientfic publication. If you will have any question about the use of QGIS feel free to ask

[yifanliu]

I'm not sure about what kind of world map you're looking for, but I suggest to ’try tmap package.