Please help me to apply this formula to find solar radiation
A. Cloud cover observations
Model Kasten and Czeplak (1980):
K = [ K ] (a1 sin h + a2) (1 + b1 Nb2)
Where, a1 and a2 are local turbidity coefficients and N = 1 for overcast skies, b1 and b2 are constants.
. Sunshine duration measurements
2. Stanhill (1983):
For Northern Hemisphere:
K = 9.31 – 0.1033 ø + 0.00030 H (unit GJm-2yr-1)
For Southern Hemisphere:
K = 10.34 – 0.1253 ø + 0.00035 H (unit GJm-2yr-1)
The Stanhill formulae applies to any world location between latitudes 20o and 55o.
Elevation differences affects the transmission path of global radiation.
Ø is latitude and H is terrain elevation in m.
Thank in advance