GetTopography: Get topographic data

In metR: Tools for Easier Analysis of Meteorological Fields

Get topographic data

Description

Retrieves topographic data from ETOPO1 Global Relief Model (see references).

Usage

GetTopography(
  lon.west,
  lon.east,
  lat.north,
  lat.south,
  resolution = 3.5,
  cache = TRUE,
  file.dir = tempdir(),
  verbose = interactive()
)

Arguments

lon.west, lon.east, lat.north, lat.south	latitudes and longitudes of the bounding box in degrees
resolution	numeric vector indicating the desired resolution (in degrees) in the lon and lat directions (maximum resolution is 1 minute)
cache	logical indicating if the results should be saved on disk
file.dir	optional directory where to save and/or retrieve data
verbose	logical indicating whether to print progress

Details

Very large requests can take long and can be denied by the NOAA server. If the function fails, try with a smaller bounding box or coarser resolution.

Longitude coordinates must be between 0 and 360.

Value

A data table with height (in meters) for each longitude and latitude.

References

Source: Amante, C. and B.W. Eakins, 2009. ETOPO1 1 Arc-Minute Global Relief Model: Procedures, Data Sources and Analysis. NOAA Technical Memorandum NESDIS NGDC-24. National Geophysical Data Center, NOAA. \Sexpr[results=rd]{tools:::Rd_expr_doi("10.7289/V5C8276M")}

Examples

## Not run: 
topo <- GetTopography(280, 330, 0, -60, resolution = 0.5)
library(ggplot2)
ggplot(topo, aes(lon, lat)) +
    geom_raster(aes(fill = h)) +
    geom_contour(aes(z = h), breaks = 0, color = "black", size = 0.3) +
    scale_fill_gradient2(low = "steelblue", high = "goldenrod2", mid = "olivedrab") +
    coord_quickmap()

## End(Not run)

metR documentation built on Oct. 14, 2024, 5:09 p.m.