SANDPIT: Integrated Assessment of Geoengineering Proposals (IAGP)

国际社会一致认为，必须避免气候变化达到危险水平。然而，分析表明，如果不彻底改变能源的来源和使用方式，地球将在本世纪晚些时候开始经历不可接受的破坏性和破坏性环境变化，这是一个非常现实的风险。如果通过减缓和适应来应对气候变化的传统方法被证明是不够的，未来可以采取哪些行动来保护环境质量、生态系统、农业、经济和社会？我们能在紧急情况下直接控制地球的温度吗？故意操纵地球气候并不是一个新奇的想法，然而，越来越多的人意识到气候变暖的潜在严重性，并对此表示关注，这导致了最近关于直接干预地球气候和自然系统以抵消全球变暖和温室气体浓度增加的其他已知影响的道德和可行性的争论。随着这个被称为“地球工程”的新研究领域在国际上的知名度越来越高，从大气中去除二氧化碳或直接改变地表吸收阳光量的想法也越来越多。建议的去除二氧化碳的方法横跨海洋和陆地生物圈，从通过向海洋表面施肥来提高海洋生产力，到添加石灰来中和二氧化碳的酸度。通过向大气中注入硫酸盐气溶胶或种植反射性更强的作物，可以实现地表的直接冷却。然而，尽管在考虑不同的地球工程方案时付出了努力和科学的聪明才智，但它们的有效性仍然无法量化，特别是在区域范围内。其中一些不太可能像设想的那样发挥作用，许多可能会产生不良的气候副作用，并对环境和社会构成风险。目前，我们没有足够的信息来为我们需要进行的关于地球工程的辩论提供信息。地球工程方案综合评估（IAGP）是一个跨学科的项目，它将开始解决我们知识上的这一差距，特别关注地球工程方案潜在的副作用和意想不到的后果。该项目将制定一个全面的评估框架（涉及利益相关者和公众），这将允许对所有主要的地球工程建议进行深入的比较。该项目的研究工具将包括地球系统的最先进的计算机表示，计算海洋环流、海冰、温室变暖、大气过程和动力学，以及海洋中碳和营养物质的循环。需要解决的重要问题包括：是否可以将不同的技术结合起来，以最大限度地发挥缓解效益并最大限度地减少不必要的风险；如何充分控制地球工程计划，并在必要时迅速“关闭”它；如何在确定效益和副作用的过程中纳入公众的意见，以便决策者做出知情的决定。该项目将地球系统建模与利益相关者和公众的审慎参与相结合，以确保评估符合各种价值观和标准，并确保将问题和社会价值观集中纳入评估。我们对不同二氧化碳去除和直接冷却方案的有效性和影响的分析结果，不仅将通过为我们的全球环境未来提供决策信息，具有直接的政策相关性，而且将精心定制，以足够清晰和有意义的方式向更广泛的受众提供信息，从而使围绕地球工程的辩论能够在社会中进一步发展。

There is international consensus that dangerous levels of climate change must be avoided. Yet without radical changes in the ways energy is sourced and used, analyses suggest that there is a very real risk that the Earth will start to experience unacceptably damaging and disruptive environmental change later this century. What future actions can be taken to safeguard environmental quality, ecosystems, agriculture, economy, and societies if the conventional approaches to tackling climate change, through mitigation and adaptation, prove insufficient? Could we take direct control of our planet's temperature in an emergency? Deliberately manipulating the Earth's climate is not a novel idea, however increasing awareness and concern about the potentially serious nature of a much warmer climate has led to recent debates regarding the ethics and feasibility of making a direct intervention in the Earth's climate and natural systems to counteract global warming and the other known impacts of increasing greenhouse gas concentrations.As this new research field, known as 'geoengineering', has gained in international profile, ideas for either removing CO2 from the atmosphere or directly altering the amount of sunlight absorbed at the surface have proliferated. Suggested means of removing CO2 span marine and terrestrial biospheres, from enhancing marine productivity by fertilizing the surface of the ocean with nutrients, to adding lime to neutralize the CO2 acidity. Direct cooling of the surface could potentially be done by injecting sulphate aerosols into the atmosphere or planting more reflective varieties of crops. However, despite the effort and scientific ingenuity being brought to bear in thinking up different geoengineering schemes, all remain un-quantified in their effectiveness, particularly at the regional scale. Some are unlikely ever to work as envisaged, and many contain the potential for undesirable climatic side-effects and risks to the environment and to society. Currently we have insufficient information to inform the debate we need to have on geoengineering. The Integrated Assessment of Geoengineering Proposals ('IAGP') is an interdisciplinary project which will begin to address this gap in our knowledge, paying particular attention to the potential for side-effects and unanticipated consequences of geoengineering schemes. The project will develop a comprehensive evaluation framework (involving stakeholders and publics), which will allow an in-depth comparison of all major geoengineering proposals. The project research tools will include state-of-the-art computer representations of the Earth system, accounting for ocean circulation, sea-ice, and greenhouse warming and atmospheric processes and dynamics, as well as the cycling of carbon and nutrients within the ocean. Important questions to be addressed include: whether different technologies can be combined to maximize mitigation benefits and minimize unwanted risks, how might geoengineering schemes be adequately controlled and 'turned off' quickly if needed, how to include the public's views in how benefits and side-effects are defined in order for policy-makers to take informed decisions. The project combines Earth system modelling and deliberative engagement with stakeholders and publics to ensure the evaluation is accountable to a variety of values and criteria and ensures that issues and society's values are centrally incorporated within the evaluation.The results of our analysis of the effectiveness and implications of different CO2 removal and direct cooling schemes will not only have direct policy relevance through informing decisions about our global environmental future, but will be carefully tailored to give wider audiences information in a sufficiently clear and meaningful way that the debates surrounding geoengineering can be progressed further within society.