Serving Gulf Stream datasets directly from R.
Use the remotes package to install directly from github.
remotes::install("BigelowLab/gstream)
NOAA’s Ocean Prediction Center provides a
FTP server](https://ftp.opc.ncep.noaa.gov/grids/experimental/GStream)
for downloads by year. We have downloaded these and repackaged into
spatial format files - these are included with the gstream package.
They also provide daily
updates.
suppressPackageStartupMessages({
library(sf)
library(dplyr)
library(gstream)
library(rnaturalearth)
})
x = read_usn() |>
dplyr::glimpse()## Rows: 3,909
## Columns: 3
## $ date <date> 2010-01-22, 2010-01-22, 2010-01-25, 2010-01-25, 2010-01-27, …
## $ wall <chr> "north", "south", "north", "south", "north", "south", "north"…
## $ geometry <MULTIPOINT [°]> MULTIPOINT ((-80.2 25), (-8..., MULTIPOINT ((-77.5…
This reads in all of the data stored with the package. We can then do a simple plot of all of the locations.
bb = sf::st_bbox(x)
coast = rnaturalearth::ne_coastline(scale = "medium", returnclass = "sf")
plot(x['wall'], pch = 3, axes = TRUE, reset = FALSE)
plot(sf::st_geometry(coast), add = TRUE)
Note that you don’t need to create the configuration file if you are not downloading data.
The daily data is hosted by by NOAA’s Ocean Prediction
Center In particular they post the US
Navy’s daily Gulf Stream point
data for the north
and south walls. These can be downloaded. We provide a mechanism for
storing the URL of the daily data, the path to where you want to store
the downloads and a simple script for downloading. The configuration can
be stored anywhere, but by default we look for it isn ~/.gstream.
cfg = read_configuration()
cfg## $usn
## $usn$rawpath
## [1] "/Users/ben/Dropbox/data/gstream/usn/raw"
##
## $usn$dailyuri
## [1] "https://ocean.weather.gov/gulf_stream_latest.txt"
##
## $usn$ftpuri
## [1] "https://ftp.opc.ncep.noaa.gov/grids/experimental/GStream"
Obviously, you will want to modify the rawpath to suit your own needs.
We then set up a cron job to make the daily download at local 6pm.
# gstream data
0 18 * * * /usr/local/bin/Rscript /Users/ben/Library/CloudStorage/Dropbox/code/projects/gsi/inst/scripts/usn_daily_download.R >> /dev/null 2>&1
The USN data is not ordered, that is the points for a given day are not following a polyline.
d = dplyr::filter(x, date == as.Date("2020-12-19"), wall == "north")
plot(sf::st_geometry(d), type = "l", axes = TRUE)
With thanks to Dewey
Dunnington
we can reorder them into a single LINESTRING.
d = dplyr::filter(x, date == as.Date("2020-01-03"), wall == "north")
do = order_usn(d)
plot(sf::st_geometry(d), type = "l", axes = TRUE, reset= FALSE)
plot(sf::st_geometry(do), type = "l", add = TRUE, col = "orange")