Package 'meteoForecast'

Access to several Numerical Weather Prediction services both in raster format and as a time series for a location.

Description

meteoForecast is a package to access outputs from Numerical Weather Prediction models both in raster format and as a time series for a location. Currenty it works with GFS, MeteoGalicia, NAM, and RAP.

Details

getRaster, getRasterDay, and getRasterDays get data inside a bounding box and provide a multilayer raster data using the RasterBrick class defined in the package raster.

getPoint, getPointDays, and getPointRuns get data for a certain location and produce a time series using the zoo class.

Author(s)

Oscar Perpiñán, with contributions from Marcelo Almeida

References

https://www.meteogalicia.gal/web/modelos/threddsIndex.action?request_locale=es

https://www.ncei.noaa.gov/thredds/catalog/model-gfs-003-files/catalog.html

https://www.ncei.noaa.gov/thredds/catalog/model-nam218/catalog.html

https://www.ncei.noaa.gov/thredds/catalog/model-rap130/catalog.html

See Also

raster zoo

---

Forecast Variables available in each model.

Description

The grepVar retrieves the XML file with the names, description, and labels of each variable available in the service, and searches for matches in the description field.

Usage

grepVar(x, service, day = Sys.Date() - 1, complete = FALSE)

Arguments

x	character string to be matched in the description field of the set of variables. Try x = "" and complete = TRUE to get the complete list of choices with the description field.
service	Character, to choose from 'meteogalicia', 'gfs', 'nam', and 'rap'
day	Date. Services change the variables availability over time.
complete	Logical, if FALSE (default) only the name of the variables is returned. If TRUE the name, label, and description columns are provided.

Value

If complete = TRUE this function provides a data.frame with three columns, name, label, and description. Use the elements of the name column to choose a variable with the argument var of getRaster and getPoint.

Source

https://mandeo.meteogalicia.es/thredds/catalogos/WRF_2D/catalog.html

https://mandeo.meteogalicia.es/thredds/catalog/gfs_0p25/fmrc/catalog.html

https://www.ncei.noaa.gov/thredds/catalog/model-nam218/catalog.html

https://www.ncei.noaa.gov/thredds/catalog/model-rap130/catalog.html

Examples

## Not run: 
## Variables available recently
grepVar('cloud', service = 'gfs', complete = TRUE)

## Variables available some days ago
grepVar('cloud', service = 'nam',
        day = Sys.Date() - 10,
        complete = TRUE)

## You can get the complete list with x = ""
grepVar("", service = 'meteogalicia', complete = TRUE)

## End(Not run)

---

NWP forecasts for a location

Description

The getPoint* functions get outputs of the NWP models run by MeteoGalicia and NCEP (GFS, RAP, NAM) for a single location.

Usage

getPoint(point, vars = "swflx", day = Sys.Date(), run = "00",
         resolution = NULL, vertical = NA, service = mfService())

getPointDays(point, vars = "swflx", start = Sys.Date(), end,
             service = mfService(), ...)

getPointRuns(point, var = "swflx",
             start = Sys.Date() - 1, end = Sys.Date(),
             service = mfService(), ...)

Arguments

point	Coordinates of the location. It can be a SpatialPoints or a numeric of length 2 (lon, lat).
var, vars	Character. The name of the variables to retrieve. Use grepVar to know what variables are available in each service. getPointRuns only works with one variable.
day	Date or character
run	Character. The meteogalicia service executes the model at OOUTC and 12UTC. Therefore run can be '00' or '12'. With GFS and NAM run can be '00', '06', '12', and '18'. The RAP service is run every hour.
start	Date or character. First day of the time period to retrieve.
end	Date or character. Last day of the time period to retrieve.
resolution	Numeric. Resolution in kilometers of the raster. Valid choices are 4, 12, and 36. It is only used with service = 'meteogalicia'.
vertical	Numeric. Vertical coordinate for variables with several levels. Its default value is NA, meaning that only the first level will be retained.
service	Character, which service to use, 'meteogalicia', 'gfs', 'nam', or 'rap'.
...	Additional arguments for getPoint

Details

These functions download data from the MeteoGalicia and NCEP (GFS, RAP, NAM) servers using the NetCDF Subset Service. The result is returned as a zoo time series object, with one or more csv files stored in the temporary folder (as defined by tempdir()).

Value

getPoint and getPointDays produce a zoo time series with a column for each variable included in vars.

The time series returned by getPoint starts at 01UTC of day if run = '00' or 13UTC if run = '12'. It spans over 4 days (96 hours) if run = '00' or 84 hours if run = '12'.

The time series returned by getPointDays starts at 01UTC of start and finishes at 00UTC of end + 1. Each day comprised in the time period is constructed with the forecast outputs corresponding to the 00UTC run of that day. Therefore, only the first 24 values obtained with getPoint are used for each day.

The time series returned by getPointRuns starts at 01UTC of start and finishes at 00UTC of end + 1. It has 4 columns, named "D3_00", "D2_00", "D1_00" and "D0_00". The column "D3_00" corresponds to the forecast results produced 3 days before the time stamp of each row, and so on.

Author(s)

Oscar Perpiñán Lamigueiro with contributions from Marcelo Almeida

References

https://mandeo.meteogalicia.es/thredds/catalogos/WRF_2D/catalog.html

https://mandeo.meteogalicia.es/thredds/catalog/gfs_0p25/fmrc/catalog.html

https://www.ncei.noaa.gov/thredds/catalog/model-nam218/catalog.html

https://www.ncei.noaa.gov/thredds/catalog/model-rap130/catalog.html

See Also

getRaster

Examples

## Not run: 
  ## If some of the next examples do not work, try using a different
  ## date. Check availability for each service with the links included in
  ## the references section.
  testDay <- Sys.Date() - 1

  ## temperature (Kelvin) forecast from meteogalicia
  tempK <- getPoint(c(0, 40), vars = 'temp', day = testDay)
  ## Cell does not coincide exactly with request
  attr(tempK, 'lat')
  attr(tempK, 'lon')
  ## Units conversion
  tempC <- tempK - 273

  library(lattice)
  ## Beware: the x-axis labels display time using your local timezone.
  Sys.timezone()

  ## Use Sys.setenv(TZ = 'UTC') to produce graphics with the timezone
  ## of the objects provided by meteoForecast.
  xyplot(tempC)

  ## Multiple variables
  vars <- getPoint(c(0, 40), vars = c('swflx', 'temp'), day = testDay)
  xyplot(vars)

  ## Vertical coordinates
  tempK1000 <- getPoint(c(0,40),
                        vars = "Temperature_surface",
                        day = testDay,
                        service ="gfs", vertical = 1000)

  ## Time sequence
  radDays <- getPointDays(c(0, 40),
                          start = testDay - 3,
                          end = testDay)
  
  xyplot(radDays)

  ## Variability between runs
  radRuns <- getPointRuns(c(0, 40),
                          start = testDay - 3,
                          end = testDay)
  xyplot(radRuns, superpose = TRUE)
  
  ## variability around the average
  radAv <- rowMeans(radRuns)
  radVar <- sweep(radRuns, 1, radAv)
  xyplot(radVar, superpose = TRUE)

## End(Not run)

---

NWP forecasts for a region

Description

The getRaster* functions get outputs of the NWP models for a region.

Usage

getRaster(var = "swflx", day = Sys.Date(), run = "00",
          frames = 'complete', box, resolution = NULL,
          names, remote = TRUE, service = mfService(),
          dataDir = ".", use00H = FALSE, ...)

getRasterDays(var = "swflx", start = Sys.Date(), end,
              remote = TRUE, dataDir = ".", ...)

getRasterDay(var = "swflx", day = Sys.Date(),
              remote = TRUE, dataDir = ".", ...)

checkDays(start, end, vars, remote = FALSE,
          service = mfService(), dataDir = '.')

Arguments

var, vars	Character. The name of the variable (or variables in checkDays) to retrieve. Use grepVar to know what variables are available in each service.
day	Date or character. In getRaster it defines the day when the forecast was produced. In getRasterDay it defines the day to be forecast.
run	Character. For example, the meteogalicia service executes the model at OOUTC and 12UTC. Therefore run can be '00' or '12'.
start	Date or character. First day of the time period to retrieve.
end	Date or character. Last day of the time period to retrieve.
frames	Numeric. It defines the number of hourly forecasts (frames) to retrieve. If frames = 'complete', the full set of frames is downloaded. For example, the meteogalicia service produces 96 hourly forecasts (frames) with run='00' and 84 frames with run='12'.
box	The bounding box, defined using longitude and latitude values. A Extent or an object that can be coerced to that class with extent: a 2x2 matrix (first row: xmin, xmax; second row: ymin, ymax), vector (length=4; order= xmin, xmax, ymin, ymax) or list (with at least two elements, with names 'x' and 'y').
resolution	Numeric. Resolution in kilometers of the raster. Valid choices are 4, 12, and 36. It is only used with service = 'meteogalicia'.
names	Character. Names of the layers of the resulting RasterBrick. If missing, a predefined vector is assigned the combination of day and hour.
remote	Logical. If TRUE (default) data is downloaded from the remote service. If FALSE the RasterBrick is produced with the files available in the local folder.
service	Character, which service to use, 'meteogalicia', 'gfs', 'nam' or 'rap'.
use00H	Logical. Only used when service is 'gfs', 'nam', or 'rap'. If FALSE (default), the first frame of each run or 00H "forecast" is not considered. This first frame is only produced for some variables. Therefore, with use00H = TRUE fewer frames that the number defined with frames could be obtained for some variables.)
dataDir	Character, path of the folder where files are stored (if remote = 'FALSE')
...	Additional arguments. Not used in getRaster.

Details

getRaster downloads data from the MeteoGalicia and NCDC (GFS, RAP, and NAM) servers using the NetCDF Subset Service. The result is returned as a RasterBrick object, with one or more NetCDF files stored in the temporary folder (as defined by tempdir()). Each frame or layer of the RasterBrick corresponds to a certain hour of the forecast.

getRasterDay uses getRaster to download the results corresponding to a certain day. If the day is in the future, the most recent forecast is downloaded with getRaster, and the corresponding frames are extracted. If the day is in the past, getRaster is used to download the corresponding frames of the forecast produced that day.

getRasterDays uses getRaster to download the results cast each day comprised between start and end using the 00UTC run. Then it subsets the first 24 frames of each result, and binds them together to produce a RasterBrick. Therefore, each frame of this RasterBrick is a forecast for an hour of the day when the forecast was cast.

checkDays explores a local folder looking for NetCDF files corresponding to a time sequence and a set of variables. It returns a Date vector comprising the days with files available for the requested variables. If remote = TRUE it only checks that start is after 2008-01-01 (first date of the archived forecasts of MeteoGalicia.)

Value

The getRaster* functions return a RasterBrick with a layer for each hour of the NWP forecast.

The time zone of the time index of this RasterBrick, stored in its z slot (accesible with getZ) is UTC.

MeteoGalicia, NAM, and RAP use the Lambert Conic Conformal projection. GFS files use longitude-latitude coordinates.

Author(s)

Oscar Perpiñán with contributions from Marcelo Almeida.

References

https://mandeo.meteogalicia.es/thredds/catalogos/WRF_2D/catalog.html

https://mandeo.meteogalicia.es/thredds/catalog/gfs_0p25/fmrc/catalog.html

https://www.ncei.noaa.gov/thredds/catalog/model-nam218/catalog.html

https://www.ncei.noaa.gov/thredds/catalog/model-rap130/catalog.html

Examples

## Not run: 

## If some of the next examples do not work, try using a different
## date. Check availability for each service with the links included in
## the references section.

testDay <- Sys.Date() - 1

## Retrieve raster data
wrf <- getRaster('temp', day = testDay)

## Display results with rasterVis
library(rasterVis)

levelplot(wrf, layers = 10:19)

hovmoller(wrf)

## Using box and frames specification
mfExtent('gfs')

cloudGFS <- getRaster('Temperature_surface',
                      day = testDay,
                      box = c(-30, 30, 30, 50),
                      service = 'gfs')

levelplot(cloudGFS, layout = c(1, 1))

mfExtent('nam')
cloudNAM <- getRaster('Temperature_surface',
                      day = testDay,
                      box = c(-100, -80, 30, 50),
                      frames = 10,
                      service = 'nam')
mfExtent('rap')
cloudRAP <- getRaster('Temperature_surface',
                      day = testDay,
                      box = c(-100, -80, 30, 50),
                      frames = 10,
                      service = 'rap')


## Day sequence of cloud cover
wrfDays <- getRasterDays('cft',
                         start = testDay - 3,
                         end = testDay + 2,
                         box = c(-2, 35, 2, 40))

levelplot(wrfDays, layers = 10:19)

## animation
levelplot(wrfDays, layout = c(1, 1), par.settings = BTCTheme)

## Hövmoller graphic
hovmoller(wrfDays, par.settings = BTCTheme, contour = TRUE, cuts = 10)

NAMDays <- getRasterDays('Temperature_surface',
                         start = testDay - 3,
                         end = testDay,
                         box = c(-100, -80, 30, 50),
                         service = 'nam')

## Extract data at some locations

st <- data.frame(name=c('Almeria','Granada','Huelva','Malaga','Caceres'),
               elev=c(42, 702, 38, 29, 448))

coordinates(st) <- cbind(c(-2.46, -3.60, -6.94, -4.42, -6.37),
                         c(36.84, 37.18, 37.26, 36.63, 39.47)
                         )
proj4string(st) <- '+proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0'


## Extract values for some locations
vals <- extract(wrf, st)
vals <- zoo(t(vals), getZ(wrf))
names(vals) <- st$name

xyplot(vals)

## End(Not run)

---

Options and Internal Variables

Description

Functions to get or set options, and to access internal parameters of the package.

Usage

getMFOption(name = NULL)
setMFOption(name, value)
mfService(service = NULL)
mfExtent(service, resolution = 12)
mfProj4(service, resolution = 12)

Arguments

name	Character, name of the option to get or set.
value	Character, value of the option to be changed.
service	Character, name of the service ('meteogalicia', 'gfs', 'nam', 'rap').
resolution	Numeric, value of the resolution (in kilometers). Only useful if service = 'meteogalicia'

Details

Use getMFOption to list the options of the package. Only one option, service, is available with this version. With setMFOption the option defined with name can be modified.

mfService, a wrapper around getMFOption and setMFOption, displays the default service if used without arguments. It modifies the default service to the value of its argument.

mfExtent and mfProj4 provides the extent and the proj4 string of the corresponding service.

Author(s)

Oscar Perpiñán Lamigueiro

Examples

mfService()

mfExtent('meteogalicia', 36)

mfExtent('nam')

mfProj4('rap')

---