As atmospheric carbon dioxide concentrations rise and climate change becomes more destructive, geoengineering has become a subject of serious consideration. By reflecting a fraction of incoming sunlight, solar geoengineering could cool the planet quickly, but with uncertain effects on regional climatology, particularly hydrological patterns. Here, we review recent work on projected hydrologic outcomes of solar geoengineering, in the context of a robust literature on hydrological responses to climate change. While most approaches to solar geoengineering are expected to weaken the global hydrologic cycle, regional effects will vary based on implementation method and strategy. The literature on the hydrologic outcomes and impacts of geoengineering demonstrates that its implications for human welfare will depend on assumptions about underlying social conditions and objectives of intervention as well as the social lens through which projected effects are interpreted. We conclude with suggestions to reduce decision-relevant uncertainties in this novel field of Earth science inquiry. ▪ The expected hydrological effects of reducing insolation are among the most uncertain and consequential impacts of solar geoengineering (SG). ▪ Theoretical frameworks from broader climate science can help explain SG's effects on global precipitation, relative humidity, and other aspects of hydroclimate. ▪ The state of the knowledge on hydrological impacts of SG is unevenly concentrated among regions. ▪ Projected hydrological impacts from SG are scenario dependent and difficult to characterize as either harmful or beneficial.

中文翻译：

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太阳能地球工程的水文后果


随着大气中二氧化碳浓度的上升和气候变化变得更具破坏性，地球工程已成为一个值得认真考虑的主题。通过反射一小部分入射阳光，太阳能地球工程可以使地球迅速降温，但对区域气候，特别是水文模式的影响不确定。在这里，我们在有关气候变化水文响应的大量文献的背景下回顾了最近关于太阳地球工程预计水文结果的工作。虽然大多数太阳能地球工程方法预计会削弱全球水文循环，但区域影响将根据实施方法和策略的不同而有所不同。关于地球工程的水文结果和影响的文献表明，其对人类福祉的影响将取决于对潜在社会条件和干预目标的假设，以及解释预计影响的社会视角。最后，我们提出了减少地球科学探究这一新领域中与决策相关的不确定性的建议。 ▪ 减少日照的预期水文效应是太阳能地球工程（SG）最不确定和最重要的影响之一。 ▪ 更广泛的气候科学的理论框架可以帮助解释SG 对全球降水、相对湿度和水文气候其他方面的影响。 ▪ 对SG 水文影响的了解在各地区的分布不均匀。 ▪ SG 的预计水文影响取决于具体情况，很难将其描述为有害或有益。