Week 1: Discussion Section

Source Materials

The following materials are modified from the tmap book.

1. Learning Objectives

Read in spatial objects
Create map with single spatial object
Create map with multiple spatial objects
Use different types of tmap plotting formats (e.g. tm_polygons(), tm_fill(), tm_dots(), etc.)
Adjust color palettes
Include essential map elements (e.g. scale bar & north arrow or graticules)
Create an interactive map
Bonus Challenge: Reproduce map using ggplot2 instead of tmap

More map making in R

There are MANY different ways to make maps in R, all with different pros/cons. Check out this resource for examples of what map making looks like in ggplot2, leaflet, and more!

2. Get Started

Open your forked version of this repository and navigate to your version controlled project for Week 1
Create a Quarto document
Load all necessary packages
Read in the spatial objects for Easter Island (Rapa Nui/Isla de Pascua):
- ei_points: file contains several points on the island
- ei_elev: raster with elevation data
- ei_borders: polygon with the island outline
- ei_roads: lines contains a road network for the island

library(here)
library(tidyverse)
library(stars)
library(sf)
library(tmap)

ei_points <- sf::read_sf(here::here("data", "easter_island", "ei_points.gpkg"))
volcanoes <- subset(ei_points, type == "volcano")
ei_elev <- stars::read_stars(here::here("data", "easter_island", "ei_elev.tif"))
ei_borders <- sf::read_sf(here::here("data", "easter_island", "ei_border.gpkg"))
ei_roads <- sf::read_sf(here::here("data", "easter_island", "ei_roads.gpkg"))

3. Your Task

Now, to meet this week’s learning objectives, your task:

Create a map of Easter Island
Create a map of Easter Island and…

…denote the island’s borders and continuous elevation
…denote the island’s volcanoes and roads
…play with the color palette and essential map elements

Create an interactive map of Easter Island