A Satellite-Based Sky Luminance Model for the Tropics

Table 3

Values of the coefficients of (11). 𝑅² is coefficient of determination.

Cloud index (n)	𝑎0	𝑎1	𝑎2	𝑎3	𝑎4	𝑅^2
0.0≤𝑛≤0.1	0.10994	0.94684	0.00001	0.09794	1.88610	0.98
0.1<𝑛≤0.2	0.09695	0.82256	0.00001	0.20491	1.15237	0.98
0.2<𝑛≤0.3	0.07836	0.88284	0.00001	0.41524	0.49970	0.96
0.3<𝑛≤0.4	−1.11928	−4.39446	0.00001	0.35793	0.35518	0.91
0.4<𝑛≤0.5	0.07381	0.71343	0.00001	0.30185	0.10157	0.89
0.5<𝑛≤0.6	−0.07553	0.55181	0.00001	0.34422	−0.18030	0.79
0.6<𝑛≤0.7	−0.11489	0.80409	0.00001	0.55921	−0.33012	0.84
0.7<𝑛≤0.8	−0.12300	0.91970	0.00001	0.79808	−0.43399	0.88
0.8<𝑛≤0.9	−0.08916	0.49959	0.00001	0.57082	−1.11957	0.82
0.9<𝑛≤1.0	0.10000	−20.00000	1.00000	−0.13300	−3.31000	0.67