CANDISE: Change-Oriented Assessments for Net-Zero Digital Services

随着气候变化的明显影响在全球显现，立即减少碳排放至关重要。英国的目标是到2035年减少78%的排放，其中2%到4%来自ICT部门。联合国信息和通信技术部门(ITU)制定了到2030年脱碳45%的目标，同时对信息和通信技术服务的需求由于越来越多地采用新的和更好的服务而持续增长。运营数据中心和网络的信息和通信技术公司，以及那些在实体互联网基础设施上提供数字软件服务的公司，开始制定自己的净零碳减排目标。现在，它们各自都需要根据具体的变化，通过具体的减排战略来实现这些目标。然而，由于现有的理解忽视了数字服务背后复杂、高度动态的信通技术供应链之间的相互作用，因此缺乏关于软件服务的哪些变化将可靠地导致碳减排的知识。目前，在推理和估计当前的碳影响时，隐含着一种会计观点，这构成了决定如何减少碳排放的基础。这是一个很大的问题。这个项目旨在建立缺失的因果理解，并调查一个框架，以预测数字服务的设计、提供和使用的变化对系统和长期环境的影响，并逐步提高我们实现净零目标的能力。我们的项目团队代表了构成ICT产品系统的整个垂直堆栈技术，从面向用户的数字服务到网络和数据中心运营商。我们有经验和能力调查各种方法，以推断和评估用户、软件提供商和基础设施运营商做出的决策对长期碳排放的影响。让我们来考虑一下，在火车出行的情况下，仅仅计算现有的碳排放和根据行动估计未来的减排之间的区别。粗略地说，使用会计方法，每名乘客每英里的燃料足迹是整列火车每英里的燃料消耗除以平均乘客人数(对于火车和轨道建设的影响，这种方法类似)。重要的是，这种每英里乘客的碳足迹不能用来估计每名不旅行的乘客可以节省的碳量。相反，让火车出行脱碳需要长期的改变，比如修改燃料类型、火车结构和时刻表。由于乘客不能根据燃料类型在火车之间自由选择，向消费者提供这一信息可能是可以接受的。然而，软件提供商在考虑他们的Net Zero计划时，不能使用类似会计风格的推理来估计云计算和网络的碳足迹，因为他们会错误地估计他们计划的较长期后果。与火车乘客相比，软件提供商通过选择架构和供应商，在设计和运营服务方面有一定的自由。软件工程师和设计人员需要了解他们的决策如何长期推动碳排放--这样他们才能知道降低视频分辨率可以节省多少碳排放？非高峰期预加载碳含量的真正好处是什么？与我们运营一些世界上最大的ICT服务的合作伙伴一起，我们研究在软件设计、运营和使用过程中所做的选择如何驱动环境影响。由此，我们研究了一个能够支持设计人员和开发人员的框架。这将使创新从系统的、因果的理解中解放出来，并为我们实现净零目标的能力提供一个阶梯般的提高。

With discernible effects of climate change manifesting globally, immediate reduction of carbon emissions is crucial. The UK aims to reduce emissions by 78% by 2035, of which 2% to 4% come from the ICT sector. The UN sector body for ICT (ITU) has set decarbonisation goals of 45% by 2030 - while demand for ICT services continues to grow from increased uptake of new and better services.The ICT companies that operate datacentres and networks, and those companies that provide digital software services 'on-top' of the physical internet infrastructure begin to set their own Net Zero goals of carbon emission reductions. Now they each need to implement these goals through concrete reduction strategies based on specific changes.However, the knowledge of what changes to software services will reliably result in carbon reductions is missing, as the existing understanding ignores the interactions between the complex, highly dynamic ICT supply chains underlying digital services. Currently, an accounting perspective is implicit in reasoning about and estimating current carbon impacts and which forms the basis for deciding how to reduce carbon. This is deeply problematic.This project aims to create the missing causal understanding and investigate a framework for anticipating the systemic, long-term environmental impact from changes to the design, provision, and use of digital services and provide a step-improvement to our ability to pursue Net-Zero goals. Our project team represents the entire vertical stack of technologies that form the ICT product system, from user-facing digital services to network and datacentre operators. We have the experience and capacity to investigate ways to reason about and assess the longer-term carbon impact from decisions taken by users, software providers, and infrastructure operators. Let's consider the difference between merely accounting for existing carbon emissions and estimating future reductions from actions in the case of train travel. Roughly, using an accounting method, the footprint per passenger per mile from fuel is the per-mile fuel consumption of the entire train divided by the average number of passengers (the approach is similar for impact from construction of trains and tracks).Importantly, such a carbon footprint per passenger-mile cannot be used to estimate the amount of carbon that could be saved per passenger that was not travelling. Instead, decarbonising train travel requires long-term changes, such as modifying fuel types, train construction, and schedules. As passengers are not free to choose between trains by their fuel types, it might be acceptable to provide this information to consumers. However, software providers must not use analogue accounting-style reasoning to estimate carbon footprints for cloud computing and networks when thinking about their Net Zero plans, as they would misestimate the longer-term consequences of their initiatives. In contrast to train passengers, software providers have a certain freedom in the design and operation of their services through their choice of architecture and suppliers. They shape demand for peak performance of infrastructure paired with instant and constant availability and so co-evolve with cloud computing and networks.Software engineers and designers thus need an understanding of how their decisions drive carbon emissions long-term - so they know e.g. What carbon savings come from reducing video resolution? What is the real carbon benefit from pre-loading content off-peak? Etc.With our partners that operate some of the world's largest ICT services, we study how environmental impact is driven by choices taken during software design, operation and use. From this, we investigate a framework that can support designers and developers. This will unlock innovation from a systemic, causal understanding and provide a step-improvement to our ability to pursue Net-Zero goals.