README.md

In NERC-CEH/spCEH: Spatial utility functions and data

title: "spCEH - spatial utility functions and data from CEH Edinburgh" author: "Peter Levy" date: "2021-08-30" output: html_document: keep_md: yes vignette: > %\VignetteIndexEntry{Vignette Title} %\VignetteEngine{knitr::rmarkdown} \usepackage[utf8]{inputenc}

spCEH is an attempt to gather together some common functions and spatial data from CEH Edinburgh. The idea is to standardise where possible such things as UK coastline data, topography data, raster grids for the UK (& Scotland, ...). We share these in an easily accessible and updateable way by building them into an R package on GitHub.

Data

So far, data sets include:

• UK coastline polygons
• altitude data
• CEH LCM land cover map
• topographic wetness index
• soil carbon

Functions

So far, the package includes functions for:

• retrieving template rasters
• masking rasters with the coastline to exclude sea (or land) cells

Planned additions

Data

• mean nitrogen deposition

Functions

• colour palette diverging from zero

Examples

Install and load

# if not already installed, install "remotes" package:
# install.packages("remotes")
remotes::install_github("NERC-CEH/spCEH")

library(spCEH)

getSpatRasterTemplate

Generate a raster grid covering the UK domain at 5-km resolution:

r <- getSpatRasterTemplate(domain = "UK", res = 5000, proj = 'OSGB')
r

## class       : SpatRaster 
## dimensions  : 260, 140, 1  (nrow, ncol, nlyr)
## resolution  : 5000, 5000  (x, y)
## extent      : 0, 7e+05, 0, 1300000  (xmin, xmax, ymin, ymax)
## coord. ref. : OSGB36 / British National Grid (EPSG:27700) 

maskByCountry

Mask out cells which are not in England or Wales:

plot(st_geometry(sfdf_uk))
r <- getSpatRasterTemplate(domain = "UK", res = 10000, proj = 'OSGB')
r <- setValues(r, 1) # add some dummy values to plot
r

## class       : SpatRaster 
## dimensions  : 130, 70, 1  (nrow, ncol, nlyr)
## resolution  : 10000, 10000  (x, y)
## extent      : 0, 7e+05, 0, 1300000  (xmin, xmax, ymin, ymax)
## coord. ref. : OSGB36 / British National Grid (EPSG:27700) 
## source(s)   : memory
## name        : lyr.1 
## min value   :     1 
## max value   :     1 

r_masked <- maskByCountry(r, c("England", "Wales"))
plot(r_masked == 1, add = TRUE)

Load some data

Data sets included in the package are loaded into memory when needed (LazyData):

get_r_alt()  # and behold, it appears

## class       : SpatRaster 
## dimensions  : 1300, 700, 1  (nrow, ncol, nlyr)
## resolution  : 1000, 1000  (x, y)
## extent      : 0, 7e+05, 0, 1300000  (xmin, xmax, ymin, ymax)
## coord. ref. : OSGB36 / British National Grid (EPSG:27700) 
## source      : r_alt_1km.tif 
## name        : r_alt_1km 
## min value   :    -3.000 
## max value   :  1177.413 

plot(get_r_alt())

NERC-CEH/spCEH documentation built on June 12, 2024, 2:45 p.m.