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Retrieval of Weather Data from WMO and NASA Surface meteorology and Solar Energy

Source: R/weather.R
weather.Rd

The function retrieves daily weather data for a site from the NASA POWER service by longitude/latitude, returning temperature, humidity, wind, solar radiation and precipitation ready for ETo and kc. A legacy station path (WMO or airport codes, from Weather Underground) is retained but that data source has been discontinued. An internet connection is required. The same data can be downloaded manually from the NASA POWER Data Access Viewer https://power.larc.nasa.gov/data-access-viewer/.

Usage

weather(
  data = NULL,
  wmo = NULL,
  airport = NULL,
  date = "YYYY-m-d",
  time = NULL,
  latitude = NULL,
  longitude = NULL,
  NASA.SSE = list(from = "YYYY-m-d", to = "YYYY-m-d"),
  folder = NULL
)

Arguments

data

dataframe that can contain all or part of the input data

wmo

numeric. World Meteorological Organization weather station code. You can use the Worldwide Station List at https://www.wunderground.com/ [Accessed on 2016-5-6] or https://www.wetterzentrale.de/ [Accessed on 2016-5-6]

airport

numeric. IATA or ICAO code. They are alphabetically listed at https://en.wikipedia.org/wiki/List_of_airports_by_IATA_code:_A [Accessed on 2016-5-6]

date

date in the form of "YYYY-mm-dd" for example "2016-01-01"

time

time in the form of "H:M" or decimal hours only. For example "14:21" or 14.35

latitude

geographical coordinates in decimal degrees. It should be negative for southern hemisphere

longitude

The longitude of the measurement site i.e. geographical coordinates in decimal degrees for the weather station. It should be negative for West and positive for East.

NASA.SSE

list giving the NASA POWER date range as list(from = "YYYY-mm-dd", to = "YYYY-mm-dd"), for example NASA.SSE = list(from = "2001-01-01", to = "2001-04-01"). NASA POWER daily data cover about 1981 to near-present: https://power.larc.nasa.gov. If the parameter is not provided, the date parameter is used, provided longitude and latitude are given.

folder

The path of the folder where the data can be written.

Value

WMO and NASE.SSE. The WMO contains hour and day data. The NASE.SSE contains meta and data. See example below.

References

Author

George Owusu

Examples

if (FALSE) { # \dontrun{
#all hours data at Lincoln Airport, Nabraska
lincoln=weather(airport = "KLNK", date="2011-08-04")
lincoln$WMO$hour
lincoln$WMO$day
#current hour data at London
london.now=weather(airport = "LON", date=format(Sys.time(), "%Y-%m-%d"),
time=format(Sys.time(), "%H:%M"))
london.now$WMO$hour
#NASA SSE data for Kumasi, Ghana
kumasi=weather(longitude = -1.5,latitude = 6.7,NASA.SSE = list(from="2001-04-01",
to="2002-04-01"))

#Hour, daily and SSE data at JFK 
JFK=weather(airport = "JFK", date="2001-02-02",time="17:20", latitude=40.6413, 
longitude=73.7781)
JFK$WMO$hour
JFK$WMO$day
JFK$NASA.SEE$data
JFK$NASA.SEE$meta

#' #Hour, daily and SSE slice data at Kotoka International Airport, ACCRA 
accra=weather(airport = "ACC", date="2001-02-02",time="17:20", latitude=40.6413, longitude=73.7781, 
NASA.SSE=list(from="2001-01-01",to="2004-01-01"))
accra$WMO$hour
accra$WMO$hour
accra$NASA.SEE$data
accra$NASA.SEE$meta

#Using wmo code
kumasi.now=weather(wmo="65442", date=format(Sys.time(), "%Y-%m-%d"),time=format(Sys.time(), 
"%H:%M"))
kumasi.now$WMO$hour

#retrieve daily data for a specific period i.e 1 month
lincoln=weather(airport = "KLNK", date=c("2011-08-04","2011-09-04"))
#kumasi and accra data for a time slice. May not work for different 
#geographical regions; write the results to a file
accrakumasi=weather(airport ="ACC", date=c("2011-08-04","2011-10-04"),
folder="C:/Users/george/Documents/")
} # }