Achieving net zero global emissions of carbon dioxide (CO₂), with declining emissions of other greenhouse gases, is widely expected to halt global warming. CO₂ emissions will continue to drive warming until fully balanced by active anthropogenic CO₂ removals. For practical reasons, however, many greenhouse gas accounting systems allow some “passive” CO₂ uptake, such as enhanced vegetation growth due to CO₂ fertilisation, to be included as removals in the definition of net anthropogenic emissions. By including passive CO₂ uptake, nominal net zero emissions would not halt global warming, undermining the Paris Agreement. Here we discuss measures addressing this problem, to ensure residual fossil fuel use does not cause further global warming: land management categories should be disaggregated in emissions reporting and targets to better separate the role of passive CO₂ uptake; where possible, claimed removals should be additional to passive uptake; and targets should acknowledge the need for Geological Net Zero, meaning one tonne of CO₂ permanently restored to the solid Earth for every tonne still generated from fossil sources. We also argue that scientific understanding of net zero provides a basis for allocating responsibility for the protection of passive carbon sinks during and after the transition to Geological Net Zero.

人们普遍预计，实现全球二氧化碳 （CO₂） 净零排放，同时减少其他温室气体的排放，将阻止全球变暖。二氧化碳排放将继续推动变暖，直到通过主动的人为去除 CO₂ 完全平衡。然而，出于实际原因，许多温室气体核算系统允许将一些“被动的”_{二氧化碳吸收，}例如由于_{二氧化碳施肥}导致的植被生长增强，作为清除物包含在人为净排放的定义中。通过包括被动的 CO₂ 吸收，名义上的净零排放不会阻止全球变暖，从而破坏《巴黎协定》。在这里，我们讨论了解决这个问题的措施，以确保残留的化石燃料使用不会导致进一步的全球变暖：应在排放报告和目标中对土地管理类别进行分类，以更好地区分被动 CO₂ 吸收的作用;在可能的情况下，声称的移除应该是被动吸收的补充;目标应承认地质净零排放的必要性，这意味着化石来源每产生一吨二氧化碳，就会将一吨_{二氧化碳永久恢复到}固体地球上。我们还认为，对净零排放的科学理解为在向地质净零排放过渡期间和之后分配保护被动碳汇的责任提供了基础。