Satellite Geolocation for Animal Tracking

Description Usage Arguments Details Value See Also Examples

Calculate the solar zenith angle for given times and locations

1	zenith(sun, lon, lat)

`sun`	list of solar time and declination computed by `solar`.
`lon`	vector of longitudes.
`lat`	vector latitudes.

zenith uses the solar time and declination calculated by solar to compute the solar zenith angle for given times and locations, using the same methods as www.esrl.noaa.gov/gmd/grad/solcalc/. This function does not adjust for atmospheric refraction see refracted.

A vector of solar zenith angles (degrees) for the given locations and times.

solar

## Approx location of Sydney Harbour Bridge
lon <- 151.211
lat <- -33.852
## Solar zenith angle for noon on the first of May 2000
## at the Sydney Harbour Bridge
s <- solar(as.POSIXct("2000-05-01 12:00:00","EST"))
zenith(s,lon,lat)