The VulnToolkit R package provides tools for summarizing and analyzing tidal data. It also includes interfaces to Permanent Service for Mean Sea Level (PSMSL) data and time series data and station-level summary data collected by National Oceanic and Atmospheric Administration (NOAA) datasets. This vignette describes the functions that interact with NOAA and PSMSL databases.
Functions that interact with web sites are challenging to work with and troubleshoot. There are many more potential sources of trouble, which makes problems difficult to isolate. Workplaces may block R from interacting with web sites. A user’s internet or the web site may be down or be slow to respond. A recent change to the website may have been incompatible with the code.
One small step that can be taken to minimize these frustrating issues is to verify that your computer has curl installed and accessible.
VulnToolkit uses curl to interact with web sites. The availability of curl can be checked by running the command
Sys.which("curl") and verifying that the curl executable is listed.
NOAA stations are referred to by their station numbers, which are available on the Tides and Currents station page linked above. We’ll use the New London, CT station (station no. 8461490).
Data can be downloaded with a call to
A benefit of
VulnToolkit is that it accommodates NOAA download limits by breaking up large data requests into multiple smaller requests, and merging the result. By doing this, a user can quickly download multiple years of 6-minute data.
Some NOAA stations also collect meteorological data. If available (check with
noaa.parameters(stn = "8461490")), meteorological data can be downloaded in the
noaa() call by setting
met = TRUE.
VulnToolkit provides access to station-level data such as tidal datums and harmonic constituents.
bport.datums <- noaa.datums(station = 8461490) # New London, CT battery.datums <- noaa.datums(station = 8518750) # Battery, NYC ### retrieve harmonic constituents bport.cons <- harcon(station = 8461490) # New London, CT bport.cons ### calculate form number formDat <- form.no(station = 8461490) # New London, CT ### Multiple stations at once: stn.list <- c("8467150", "8461490", "9454240") formDat2 <- form.no(stn.list)
PSMSL data is accessed by two functions.
psmsl.stations returns a dataframe with all of the PSMSL stations, and
psmsl provides an interface to the actual sea level data. PSMSL data are in monthly or annual time scales, and span the globe.
psmsl.stns <- psmsl.stations(country = "USA", sort.by = "name") ### using the psmsl.stations call to define stations data.v1 <- psmsl(station = psmsl.stns[c(42, 70), 1]) ### call stations by name or ID data.v2 <- psmsl(station = c("DEPOE BAY", "JUNEAU"), interval = "monthly") data.v3 <- psmsl(station = c(1372, 12), interval = "monthly") data.v4 <- psmsl(station = c("DEPOE BAY", 12), interval = "monthly")