Document Type
Article
Publication Date
2025
DOI
10.1119/5.0210890
Publication Title
The Physics Teacher
Volume
63
Issue
2
Pages
129
Abstract
Question 1: If I₀ is the solar irradiance (power per unit area, W/m²) reaching my head, express the intensity on the side of my face (Is) in terms of θ. Assume for now that the irradiance is independent of path length through the atmosphere and that my face is normal to the direction θ = 90°.
Using the 1962 U.S. Standard Atmosphere,² Hottel (1976)³ expressed the solar irradiance using the formula
I = I₀(a₀ + a₁e−k sec θ), where A is the elevation in kilometers and
a₀ = 0.4237 − 0.00821(6 − A)²; a₁ = 0.5055 + 0.00595(6.5 − A)² and
k = 0.2711 + 0.01858(2.5 − A)².
Rights
© Copyright 2026 AIP Publishing LLC. All rights reserved.
This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in
Adam, J. (2025). Suntan (and other solar trigonometric functions). The Physics Teacher, 63(2), 129.
and may be found at https://doi.org/10.1119/5.0210890
Original Publication Citation
Adam, J. (2025). Suntan (and other solar trigonometric functions). The Physics Teacher, 63(2), 129. https://doi.org/10.1119/5.0210890
ORCID
0000-0001-5537-2889 (Adam)
Repository Citation
Adam, John, "Suntan (and Other Solar Tigonometric Functions)" (2025). Mathematics & Statistics Faculty Publications. 322.
https://digitalcommons.odu.edu/mathstat_fac_pubs/322
Included in
Applied Mathematics Commons, Other Oceanography and Atmospheric Sciences and Meteorology Commons, The Sun and the Solar System Commons