Kasting J F
NASA Ames Research Center, Moffett Field, CA 94035, USA.
Orig Life. 1984;14(1-4):75-82. doi: 10.1007/BF00933642.
One-dimensional radiative convective and photochemical models are used to estimate the vertical temperature structure and composition of the earth's prebiotic atmosphere. Greatly enhanced CO2 levels (100-1000 times present) are required to keep the mean surface temperature above freezing in the face of decreased solar luminosity during the earth's early history. Such high CO2 partial pressures would have affected the atmospheric oxidation state by facilitating the photochemical production of soluble species including H2O2 and H2CO. Oxidation of ferrous iron in the oceans by H2O2 dissolved in rainwater should have kept the atmospheric H2 mixing ratio above 2x10(-4) and the ground-level O2 mixing ratio below 10(-11), regardless of the magnitude of the rate of volcanic release of reduced gases.
一维辐射对流和光化学模型被用于估算地球前生物大气的垂直温度结构和组成。在地球早期历史中，面对太阳光度下降的情况，需要大幅提高二氧化碳水平（比目前高100至1000倍）才能使地表平均温度保持在冰点以上。如此高的二氧化碳分压会通过促进包括过氧化氢和甲醛在内的可溶性物种的光化学产生来影响大气氧化态。溶解在雨水中的过氧化氢对海洋中 ferrous iron 的氧化作用应能使大气中氢气的混合比保持在2×10⁻⁴以上，地面氧气的混合比保持在10⁻¹¹以下，而与还原气体火山释放速率的大小无关。
