We investigate the dynamics of a water pumping mechanism driven by temperature variations in the lunar subsurface. The thermal environment at three polar sites and three sites in the Clavius region was simulated, taking into account local terrain and scattered radiation. A separate heat and mass transfer model was used to simulate depth‐dependent, temperature‐dependent, and pressure‐dependent properties of the lunar subsurface. The results suggest that diurnally varying heat fluxes create suitable conditions for water migration at many sites across the lunar surface. Enabled by a constant supply to the lunar surface, water molecules typically migrate a few centimeters deep via the formation of distinct concentration peaks, and a downward flux driven by the repeated desorption and resorption. With a constant supply rate of 10⁻¹⁵ kg/(m² s), the quantity of adsorbed water stored at Ga timescales reaches values on the order of 10⁻¹⁰ to 10⁻⁷ mol/m² at the investigated sites. Based on our results, we present a new relation for the water migration depth that takes into account the ratios of surface temperatures. The results of a sensitivity analysis show that the desorption activation energy is a dominant factor for the quantity and depth of water migration. In addition to long‐term accumulation of subsurface adsorbate, the model shows that temporarily captured water at shallower depths can be released during the lunar day at quantities of up to several µg m⁻². This, as well as exposure of shallow water disturbed by impacts, may be a relevant source for surface water in illuminated areas.

中文翻译：

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月球上水的地下迁移动力学

我们研究了由月球地下温度变化驱动的抽水机制的动力学。考虑到当地地形和散射辐射，模拟了克拉维斯地区三个极地和三个地点的热环境。一个单独的传热传质模型被用来模拟月球地下的深度依赖，温度依赖和压力依赖的特性。结果表明，昼夜变化的热通量为月球表面许多位置的水迁移创造了合适的条件。由于对月球表面的持续供应，水分子通常会通过形成明显的浓度峰以及由反复解吸和吸收驱动的向下通量而迁移至几厘米深。恒定供应率为10^-15  kg /（m ²  s），在Ga时标下存储的吸附水量在研究地点达到10 ^-10至10 ^-7  mol / m ²的量级。根据我们的结果，我们提出了考虑表面温度比值的水迁移深度的新关系。敏感性分析的结果表明，解吸活化能是水迁移的数量和深度的主要因素。该模型表明，除了地下吸附物的长期积累外，在阴暗时期，临时捕获的水可以以几微克·m ^-2的量释放。。这以及受冲击干扰的浅水暴露，可能是照明区域中地表水的重要来源。