In jsta/glwdr: Global Lakes and Wetlands Data from R

knitr::opts_chunk$set(
  comment = "#>",
  collapse = TRUE,
  warning = FALSE,
  message = FALSE,
  fig.width = 10,
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glwdr is an R interface to the Global Lakes and Wetlands Database. Capabilities are limited to fetching the data from external sources, caching locally with the rappdirs package, and loading from this cache on demand. Although plotting and anaylsis is left to the package user, this document demonstrates some possibilities.

Installation

devtools::install_github("jsta/glwdr")

Load Package

library(glwdr)

Usage

Level 1

glwd_get(level = 1)

dt <- glwd_load(level = 1)

library(glwdr)

dt <- suppressMessages(glwd_load(level = 1))

library(maps)
library(sp)

dt <- dt[dt$COUNTRY == "United States" &
         dt$LAT_DEG < 56 &
         dt$AREA_SKM < 30000,] 

map("state")
plot(dt, add = TRUE, col = "blue")
axis(1); axis(2)

dt@data[1:5,]

Level 2

glwd_get(level = 2)

dt <- glwd_load(level = 2)

library(glwdr)

dt <- suppressMessages(glwd_load(level = 2))

library(ggplot2)
library(raster)

states <- map_data("state")
states <- glwdr:::map_data_to_spdf(states)
projection(dt) <- projection(states)

map("state")
plot(dt[states,], add = TRUE, border = "blue")
key <- data.frame(TYPE = c("Lake", "Reservoir", "River"),
                  COL = c("blue", "red", "lightblue"))
dt <- merge(dt, key, all.x = TRUE, all.y = FALSE)
plot(dt[states,], add = TRUE, col = dt[states, ]$COL)
axis(1); axis(2)

Level 3

glwd_get(level = 3)

dt <- glwd_load(level = 3)

library(glwdr)

dt <- suppressMessages(glwd_load(level = 3))

map("world")
plot(dt, breaks = 1:12, col = viridis::viridis(12), add = TRUE)
axis(1); axis(2)

References

Lehner, B., Döll, P.: Development and validation of a global database of lakes, reservoirs and wetlands, Journal of Hydrology, Volume 296, Issues 1–4, 20 August 2004, Pages 1-22, http://dx.doi.org/10.1016/j.jhydrol.2004.03.028.

jsta/glwdr documentation built on Feb. 17, 2021, 7:02 p.m.