cal_extraterrestrialRadiation_for_shorter {simET}

Calculating extraterrestrial radiation for hourly or shorter periods

Description

Calculating extraterrestrial radiation for hourly or shorter periods

Usage

cal_extraterrestrialRadiation_for_shorter(lat, J, t, lz, lm, t1)

Arguments

lat

latitude (radian), positive for the northern hemisphere and negative for the southern hemisphere.

J

is the number of the day in the year between 1 (1 January) and 365 or 366 (31 December).

t

standard clock time at the midpoint of the period (hour). For example for a period between 14.00 and 15.00 hours, t = 14.5.

lz

longitude of the centre of the local time zone (degrees west of Greenwich). For example, Lz = 75, 90, 105 and 120° for the Eastern, Central, Rocky Mountain and Pacific time zones (United States) and Lz = 0° for Greenwich, 330° for Cairo (Egypt),and 255° for Bangkok (Thailand), radian.

lm

longitude of the measurement site (degrees west of Greenwich) radian.

t1

length of the calculation period (hour)

Value

A vector for extraterrestrial Radiation (MJ m-2 hour-1)

References

Allen, R. G., Pereira, L. S., Raes, D., & Smith, M. FAO Irrigation and drainage paper No. 56. Rome: Food and Agriculture Organization of the United Nations, 1998.