The Faint Young Sun Paradox: A Simplified Thermodynamic Approach

Table 2

Possible scenarios of ancient surface temperatures under maximum ecological conditions. For the first row data 𝑅=0.95 was considered.

Albedo 𝜌	Greenhouse coefficient 𝛾	Solar constant 𝑆/𝑆0 (normalized)	Time BP (Gyr)	Surface temperature, 𝑇1 (K)
0.17	0.06	0.7-0.8	4.5–3.6	293.6–303.6
0.40	0.0	0.81	2.297	273.1
	0.1	0.73	4.253	273.0
0.45	0.0	0.88	1.568	273.1
	0.1	0.80	2.875	273.2
	0.15	0.76	3.631	273.4
	0.20	0.71	4.697	273.7
0.50	0.1	0.88	1.568	273.2
	0.15	0.83	2.355	273.3
	0.20	0.79	3.056	373.5
	0.25	0.74	4.045	273.1