Targeted geoengineering aims to tackle a global scale impact of climate warming by addressing local or regional systemic interventions. We consider three examples: conserving the West Antarctic ice sheet by limiting rates of ice discharge or increasing snow accumulation, thereby reducing global sea level rise; transforming the Arctic permafrost zone into steppe grassland; raising the albedo of Arctic sea ice. There are important differences between targeted interventions and archetypal solar geoengineering, which ideally would have global governance structures, while some targeted interventions may be done entirely under the accepted purview of small numbers of nation states. For example, the West Antarctic ice sheet is governed by the consultative members of the Antarctic Treaty. Of the interventions we look at, only ice sheet conservation seems viable and efficient relative to solar geoengineering. Many important treaties and conventions rely on the precautionary approach. While at first glance this principle seems to argue against targeted interventions, we argue that it may in fact do the opposite. Given the existence of irreversible thresholds in many natural systems, the precautionary approach may be better upheld by a targeted intervention that prevents a system from changing in ways that cannot be undone.

中文翻译：

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有针对性的地球工程：具有全球意义的本地干预

定向地球工程旨在通过解决本地或区域系统性干预措施来解决全球气候变暖的影响。我们考虑三个例子：通过限制冰的排放速度或增加积雪来保护南极冰原，从而减少全球海平面上升；将北极多年冻土带转变为草原草原；提高北极海冰的反照率。有针对性的干预措施与原型太阳能地球工程之间存在重要差异，理想情况下，这将具有全球治理结构，而某些有针对性的干预措施可能完全在少数民族国家公认的范围内进行。例如，南极西部冰原是由《南极条约》的协商成员管辖的。在我们研究的干预措施中，相对于太阳能地球工程而言，只有冰盖保护才是可行和高效的。许多重要的条约和公约都依靠预防措施。乍一看，该原则似乎与有针对性的干预相抵触，但我们认为它实际上可能相反。考虑到许多自然系统中都存在不可逆的阈值，可以通过有针对性的干预措施来更好地支持预防措施，这种干预措施可以防止系统以无法撤消的方式发生变化。