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Earth’s Energy Balance at the Top of Atmosphere (TOA)
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Edit the inputs in blue cells; outputs update automatically.
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Solar constant S0 (W/m^2):1361Notes:
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Planetary albedo α (0–1):0.5
• S0 is measured on a surface perpendicular to sunlight.
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• Divide by 4 to distribute over Earth’s sphere.
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Stefan–Boltzmann constant σ (W m^-2 K^-4):
5.67E-08• Absorbed = (1 - α) × S0/4.
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• At equilibrium: outgoing IR = absorbed solar.
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Mean incoming per unit area S0/4 (W/m^2):340.25
• T_eff from Stefan–Boltzmann: F = σ T^4.
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Absorbed solar (1-α)·S0/4 (W/m^2):170.13
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Equilibrium emission F_out (W/m^2):170.13
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Effective emission temperature T_eff (K):234.04
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Effective temperature (°C):-39.11
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