worldmet (version 0.10.0)

importNOAAlite: Import "Lite" Meteorological data from the NOAA Integrated Surface Database (ISD)

Description

This function is an alternative to importNOAA(), and provides access to the "Lite" format of the data. This a subset of the larger importNOAA() dataset featuring eight common climatological variables. As it assigns the nearest measurement to the "top of the hour" to the data, specific values are likely similar but different to those returned by importNOAA(). Read the technical document for more information.

Usage

importNOAAlite(code = "037720-99999", year = 2025, quiet = FALSE)

Value

Returns a data frame of surface observations. The data frame is consistent for use with the openair package. Note that the data are returned in GMT (UTC) time zone format. Users may wish to express the data in other time zones, e.g., to merge with air pollution data. The lubridate package is useful in this respect.

Arguments

code

The identifying code as a character string. The code is a combination of the USAF and the WBAN unique identifiers. The codes are separated by a “-” e.g. code = "037720-99999".

year

The year to import. This can be a vector of years e.g. year = 2000:2005.

quiet

If FALSE, print missing sites / years to the screen, and show a progress bar if multiple sites are imported.

Author

Jack Davison

Details

Note the following units for the main variables:

date

Date/time in POSIXct format. **Note the time zone is UTC and may need to be adjusted to merge with other local data.

latitude

Latitude in decimal degrees (-90 to 90).

longitude

Longitude in decimal degrees (-180 to 180). Negative numbers are west of the Greenwich Meridian.

elev

Elevation of site in metres.

ws

Wind speed in m/s.

wd

Wind direction in degrees. 90 is from the east.

air_temp

Air temperature in degrees Celcius.

atmos_pres

The sea level pressure in millibars.

dew_point

The dew point temperature in degrees Celcius.

precip_6

6-hour precipitation in mm.

precip_1

1-hour precipitation in mm.

sky

Sky Condition Total Coverage Code.

The data are returned in GMT (UTC). It may be necessary to adjust the time zone when combining with other data. For example, if air quality data were available for Beijing with time zone set to "Etc/GMT-8" (note the negative offset even though Beijing is ahead of GMT. See the openair package and manual for more details), then the time zone of the met data can be changed to be the same. One way of doing this would be attr(met$date, "tzone") <- "Etc/GMT-8" for a meteorological data frame called met. The two data sets could then be merged based on date.

See Also

getMeta() to obtain the codes based on various site search approaches.

Other NOAA ISD functions: getMeta(), getMetaLive(), importNOAA()

Examples

if (FALSE) {
heathrow_lite <- importNOAAlite(code = "037720-99999", year = 2025)
}