Search arXivSearch

arXiv · 2102.02622

The climate impact of ICT: A review of estimates, trends and regulations

Abstract

In this report, we examine the available evidence regarding ICT's current and projected climate impacts. We examine peer-reviewed studies which estimate ICT's current share of global greenhouse gas (GHG) emissions to be 1.8-2.8% of global GHG emissions. Our findings indicate that published estimates all underestimate the carbon footprint of ICT, possibly by as much as 25%, by failing to account for all of ICT's supply chains and full lifecycle (i.e. emissions scopes 1, 2 and fully inclusive 3). Adjusting for truncation of supply chain pathways, we estimate that ICT's share of emissions could actually be as high as 2.1-3.9%. There are pronounced differences between available projections of ICT's future emissions. These projections are dependent on underlying assumptions that are sometimes, but not always, made explicit - and we explore these in the report. Whatever assumptions analysts take, they agree that ICT will not reduce its emissions without a major concerted effort involving broad political and industrial action. We provide three reasons to believe ICT emissions are going to increase barring a targeted intervention, and we note that in light of these, it seems risky to assume that ICT will, by default, assist in the attainment of climate targets. Based on our analysis, we find that not all carbon pledges in the ICT sector are ambitious enough to meet climate targets. We explore the underdevelopment of mechanisms for enforcing sector-wide compliance, and contend that without a global carbon constraint, a new regulatory framework is required to keep the ICT sector's carbon footprint in alignment with the Paris Agreement. We further contend that a global carbon constraint should be viewed as a significant opportunity for the ICT sector, as efficiencies within and enabled by ICT would be even greater enablers of productivity and utility than they are today.

Explore related subjects

Keep this discovery

BibTeXRIS

Charlotte Freitag, Mike Berners-Lee, Kelly Widdicks, Bran Knowles, Gordon Blair, Adrian Friday. 2021-02-03. The climate impact of ICT: A review of estimates, trends and regulations. https://arxiv.org/abs/2102.02622

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Energy pathway variety and the progress of the energy transition in European countries

The integration of new energy forms into existing energy infrastructure has emerged as a critical challenge in the context of the pursuit of a sustainable energy transition. One of the main challenges is understanding how this integration takes place not only from the introduction, but also as energy follows existing paths or creates new ones through which it is transformed and used by different activities. Here we introduce techniques from network science to analyse this process for the case of 29 European countries between 1992 and 2021. We study how new energy forms increase or decrease the variety (heterogeneity) of paths through the system of each country by establishing new ones and replacing or phasing out existing ones. We find that the transition to systems based on renewable energy is characterised by an initial increase in the variety of paths while the heterogeneity of paths decreases at the end of the transition, when the proportion of non-renewables in the system tends to zero. We then demonstrate that greater heterogeneity (complexity) is associated with larger annual fluctuations in the proportion of non-renewable sources in the system, establishing a direct relationship between the progress of the transition and the complexity of the energy system in which it occurs. This contributes to the understanding of general properties of the dynamics of the energy transition and effects that accelerate or deter it.

physics.soc-ph

Fundamental limits to identifying node and tie memory in temporal networks: marginal artefacts and spreading dynamics

Temporal-network models attribute memory in contact data to either node self-excitation (branching ratio n_node) or tie reinforcement (kappa), carrying major consequences for epidemic spreading. We prove that when event initiators are observed, the two mechanisms are orthogonal: the Fisher information is block-diagonal and neither trades off against the other. In undirected proximity data, where initiators are unobserved, marginalising over them couples the mechanisms into a structural confound that survives posterior smoothing. On empirical proximity, messaging, and email records, however, a cruder failure dominates: fitted node memory is pinned to the inter-event marginal law and remains virtually invariant across latent label posterior samples (coefficient of variation below 1%). An inter-event-order shuffle test and burstiness-memory diagnostics reveal that exponential-Hawkes node memory is recovered from none, while tie reinforcement remains identifiable throughout. This near-unidentifiability is intrinsic, not an artefact of the exponential kernel: refitting flexible scale-free (sum-of-exponentials) kernels on synthetic power-law self-exciting processes fails to distinguish genuine node memory from memoryless renewal controls, with identical collapses recurring on algorithmic networks (edit bots, cloud microservices) and cortical spiking. Downstream epidemic consequences are quantitative: simulations fitted to empirical contact records under-predict outbreak sizes by up to a factor of 2.5 and shift the epidemic threshold. We conclude that observational temporal networks face a two-fold identifiability boundary: contact directionality is essential to decouple tie reinforcement, whereas heavy-tailed node self-excitation is intrinsically unidentifiable from contact timings alone.

physics.soc-ph

Assessing extreme flood impacts on urban rail transit: A passenger-oriented, resilience-informed framework

Urban rail transit systems (URTSs) are increasingly exposed to extreme floods following heavy precipitation, yet passenger travel impacts are often assessed through delay-based indicators that overlook infeasible journeys under large-scale disruptions. This study develops a passenger-oriented, resilience-informed framework for assessing flood impacts on URTS journeys from disruption onset to recovery completion. The framework presents a novel six-category classification of journey impacts, explicitly considering rerouting, alternative station use, and a delay threshold. It is demonstrated through hourly dynamic simulations of 15 London URTS lines under 30-year, 100-year, and 1,000-year flood risk scenarios. Results indicate that severe flood disruptions lead to substantial unsatisfied demand, driven primarily by unavailable routes rather than unacceptable delays. Compared with finer behaviour adjustments, rerouting dominates travel impacts. These findings highlight the significance of moving beyond delay-based assessment and provide valuable evidence on essential behavioural mechanisms for strategic-level stress testing intended to inform URTS flood resilience intervention planning.

physics.soc-ph