Call the Quick TUV calculator web server and return a source_spct
object with the simulated spectral energy irradiance data.
qtuv_s.e.irrad(
w.length = list(wStart = 280, wStop = 420, wIntervals = 140),
sun.elevation = NULL,
geocode = data.frame(lon = 0, lat = 51.5, address = "Greenwich"),
time = lubridate::now(),
tz = NULL,
locale = readr::default_locale(),
ozone.du = 300,
albedo = 0.1,
ground.altitude = 0,
measurement.altitude = NULL,
clouds = data.frame(optical.depth = 0, base = 4, top = 5),
aerosols = data.frame(optical.depth = 0.235, ssaaer = 0.99, alpha = 1),
num.streams = 2,
spectra = list(direct = 1, diffuse.down = 1, diffuse.up = 0),
added.vars = NULL,
label = "",
server.url = "https://www.acom.ucar.edu/cgi-bin/acom/TUV/V5.3/tuv",
file = NULL
)qtuv_m_s.e.irrad(
w.length = list(wStart = 280, wStop = 420, wIntervals = 140),
sun.elevation = NULL,
geocode = data.frame(lon = 0, lat = 51.5, address = "Greenwich"),
time = lubridate::now(),
tz = NULL,
locale = readr::default_locale(),
ozone.du = 300,
albedo = 0.1,
ground.altitude = 0,
measurement.altitude = NULL,
clouds = data.frame(optical.depth = 0, base = 4, top = 5),
aerosols = data.frame(optical.depth = 0.235, ssaaer = 0.99, alpha = 1),
num.streams = 2,
spectra = list(direct = 1, diffuse.down = 1, diffuse.up = 0),
added.vars = NULL,
label = "",
server.url = "https://www.acom.ucar.edu/cgi-bin/acom/TUV/V5.3/tuv",
file = NULL
)
In the case of qtuv_s.e.irrad(), a source_spct object obtained
by finding the center of each wavelength interval in the Quick TUV output
file, and adding the variables listed in added.vars. In the case of
qtuv_m_s.e.irrad(), a source_mspct object containing a collection of
such spectra.
list of parameters describing the wavelengths, or a numeric vector from which the parameters will be constructed.
numeric Angle in degrees above the horizon. If NULL its
value is computed from geocode and time, otherwise
arguments passed to these two parameters are ignored.
data.frame with variables lon and lat as numeric values
(degrees), and character variable address; nrow > 1, allowed for collections.
A "vector" of POSIXct time, with any valid time zone (TZ) is allowed, default is current time.
character Time zone is by default read from the file.
The locale controls defaults that vary from place to place. The
default locale is US-centric (like R), but you can use
locale to create your own locale that controls things
like the default time zone, encoding, decimal mark, big mark, and day/month
names.
numeric Ozone column in Dobson units.
numeric Surface albedo (= reflectance) as a fraction of one.
numeric Altitudes above sea level expressed in km.
data.frame Parameters optical.depth (vertical), top and
base expressed in km; nrow > 1, allowed for collections.
data.frame Parameters optical.depth (total extinction), ssaaer
(cloud single scattering albedo) and alpha (wavelength dependence of
optical depth); nrow > 1, allowed for collections.
integer Number of streams used in computations, 2 or 4.
named list with weights for the different components of the spectrum.
character vector Accepted member values are "sun.elevation",
zenith.angle, "date" and "ozone.du".
character string, but if NULL the value of file is
used, and if NA the "what.measured" attribute is not set.
character The URL used to access the Quick TUV calculator server.
character The name under which the file returned by the server is
locally saved. If NULL a temporary file is used and discarded
immediately. File paths are supported when valid.
If a file name is passed as argument, the data as downloaded are saved into persistent files, one file per spectrum. The names of the saved files always end in `.txt`.
This function connects to a server managed by UCAR, the
University Corporation for Atmospheric Research located in the U.S.A. to
obtain simulated spectral data. UCAR manages the U.S. National Science
Foundation National Center for Atmospheric Research (NSF NCAR) on behalf of
NSF. As any download with the HTTPS protocol, using this function entails
some risk. To minimize the risk, the returned page is saved as plain text,
checked for conformity with the expected content, and if valid decoded into
an R data object. When using the default argument file = NULL, the
file used is a temporary one and is deleted before the function returns the
call, irrespective of it being conformant or not.
The administrators of the Quick TUV Calculator at UCAR suggest a maximum load of approximately 100 spectral simulations per day and user. For larger workloads they encourage the local installation of the TUV model which is open-source and freely available. A local installation, also allows access to the full set of input parameters and outputs. Currently a local instance of the TUV model can be called from R with package 'foqat'.
The Quick TUV calculator, is an on-line freely accessible server
running the TUV atmospheric chemistry and radiation transfer model with a
simplified user interface. In this case, version 5.3 is called passing the
parameter values passed as arguments in the call to
qtuv_s.e.irrad(). The response is saved in a text file that is
subsequently read with function read_qtuv_txt() into a
source_spct object.
Function qtuv_m_s.e.irrad() calls qtuv_s.e.irrad() repeatedly
accepting a numeric vector longer than one as argument, for parameters:
sun.elevation, time or ozone.du, and data frames with
nrow >= 1. In a given call, only one parameter at a time can obey multiple
values, with others currently truncated to the first value.
The formal parameter names are informative and consistent with other
functions in the R for Photobiology Suite and differ from the short names
used for the parameters in the FORTRAN code of the TUV model. In the case
of w.length two ways of specifying wavelengths are supported. Some
defaults also differ from those of the Quick TUV calculator.
In the current implementation, qtuv_m_s.e.irrad(), accepts multiple
values as arguments for only one parameter at a time. In the case of
elevation, both `ground.elevation` and `measurement.elevation` can have
each one or more values. When too many values are passed in the call, only
the first one is used.
https://www.acom.ucar.edu/Models/TUV/Interactive_TUV/. This
URL could change in the future as well as the server URL. The formal
parameter server.url was included only for use in such a case.
Sasha Madronich (2017-2021) Tropospheric Ultraviolet and Visible radiation (TUV) model. https://www2.acom.ucar.edu/modeling/tropospheric-ultraviolet-and-visible-tuv-radiation-model. Visited on 2024-08-29.