With the promotion of carbon neutrality and carbon peaking goals, the construction of low-carbon cities and related quantitative assessments have become hot topics in the field of urban planning and design. The Intergovernmental Panel on Climate Change (IPCC) points out that the net emissions of anthropogenic greenhouse gases have continued to rise over the past decade, with the average annual emissions higher than any previous decade. Without additional climate change mitigation policies, global warming could lead to a temperature increase of 3.5°C by 2100. Therefore, advancing the implementation of low carbon policies is of utmost urgency. Currently, the focus of low-carbon urban construction at home and abroad has shifted from macro-level conceptual introduction and review towards the analysis of specific issues and the application of digital technologies at the micro level. However, existing reviews on carbon assessment tools have several limitations. To address the aforementioned limitations, The paper entitled "Towards Digitalized Urban Planning and Design of Low-Carbon Cities: Evolution and Application Review of Assessment Tools", which was published on the journal of Landscape Architecture Frontiers, systematically categorizes, reviews, and compares the functional features, assessment dimensions, and applicable scenarios of existing assessment tools for digitalized low-carbon urban planning and design, and discusses their application shortcomings in planning and design practice.
Typical carbon assessment tools as the research subjects in this study were selected through the literature screening and validation by Google Scholar. A total of 19 assessment tools were finally selected for the study, which are categorized into two major types by scale and function.
City-scale carbon assessment tools can be roughly classified into three categories by function: energy system and policy analysis, urban climate policy analysis, and carbon emission prediction based on land use types. Over the past decade, carbon assessment tools at the district-/neighborhood-scale have become a focus of attention for universities and research institutions. They combine energy system analysis and energy demand prediction to evaluate the carbon emissions and environmental performance of planning and design schemes. Such tools can generally be divided into two categories: operational energy consumption simulation, and embodied carbon and carbon sink estimation.
Based on the energy demands, carbon emissions, and sustainable development elements of different sectors in cities, the study summarizes the 12 and 9 measuring dimensions of the city-scale and district-/neighborhood-scale carbon assessment tools, respectively.
For the city-scale tools, building, industrial and manufacturing, commercial and business, and transportation are the main sectors of urban carbon emissions, which also constitute common dimensions among the carbon assessment tools. Other major dimensions include electricity, sewage treatment, and solid waste management. City-scale carbon assessment tools quantitatively evaluate the above dimensions mainly based on macro energy consumption data in economy and land use.
At the district/neighborhood scale, simulation tools for operational energy consumption are mainly used to predict energy demand and usually combined with microclimate and thermal comfort assessments. The tools for operation energy consumption simulation mainly refer to building form and attributes data and climate data, and the ones for embodied carbon and carbon sink estimation primarily refer to data of the land use types, materials, and structures of buildings, landscapes, and infrastructure.
In the future, carbon assessment tools will see advance in global applicability, multidisciplinary coverage, full life-cycle calculation, economic balance, and data visualization. The combination of AI and other intelligent technologies will greatly increase the efficiency of carbon assessment in practice and enable carbon assessment tools to better support urban planning and design practices.
