Get sea ice data at ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/shapefiles.
rnoaa
Install and load rnoaa
into the R session.
If you're on Windows, you may have to install Rtools. Run devtools::has_devel()
. If you get a TRUE
, you're okay. If not, install Rtools.
install.packages("devtools")
devtools::install_github("ropensci/rnoaa")
library('rnoaa')
library('plyr')
urls <- sapply(seq(1979, 1990, 1), function(x) seaiceeurls(yr = x, mo = 'Feb', pole = 'S'))
out <- lapply(urls, seaice)
head(out[[1]])
#> long lat order hole piece id group
#> 1 -2125000 1950000 1 FALSE 1 0 0.1
#> 2 -2050000 1950000 2 FALSE 1 0 0.1
#> 3 -2050000 1925000 3 FALSE 1 0 0.1
#> 4 -1925000 1925000 4 FALSE 1 0 0.1
#> 5 -1925000 1900000 5 FALSE 1 0 0.1
#> 6 -1875000 1900000 6 FALSE 1 0 0.1
urls <- seaiceeurls(mo = 'Apr', pole = 'N', yr = 1990)
out <- seaice(urls)
library('ggplot2')
ggplot(out, aes(long, lat, group = group)) +
geom_polygon(fill = "steelblue") +
theme_ice()
urls <- seaiceeurls(mo = 'Apr', pole = 'N')[1:10]
out <- lapply(urls, seaice)
names(out) <- seq(1979, 1988, 1)
df <- ldply(out)
library('ggplot2')
ggplot(df, aes(long, lat, group = group)) +
geom_polygon(fill = "steelblue") +
theme_ice() +
facet_wrap(~.id)