Urban metabolism case studies have been undertaken for more than 40 years, with an increased uptake in this field since the turn of the century. At the heart of these studies lies data, just like in most research fields.
Literature has identified a number of recurring challenges that urban metabolism researchers face, including the difficulty in accessing information, the scattered nature of data, inconsistent formats, and difficulties in unpacking the “black box”. As a result, most of these studies require a time-consuming and labor-intensive data gathering process.
Metabolism of Cities aims to facilitate this process by creating an open source platform that collects the data centrally and makes it accessible to everyone. This is done through a number of different tools and sections. Launched in 2017, Metabolism of Cities developed a Global Urban Metabolism Dataset (GUMD). This dataset centralizes indicators and other data points published in academic case studies. In 2019, Metabolism of Cities launched the successor to this system: MultipliCity. This is a larger data framework that revolves around building data portals for individual cities, similar to city dashboards. Through these data portals, data on resource flows, stocks, and infrastructure can be uploaded by volunteers and downloaded by researchers and other interested parties.
Global Urban Metabolism Dataset (GUMD)
In 2017, the open source Metabolism of Cities website launched a global urban metabolism dataset that centralises urban metabolism data, indicators and research outcomes. The team manually extracted data from a variety of research studies that have calculated particular values (material extraction, emissions, construction material use, imports, exports, etc.) for an urban/provincial region. By creating one large masterlist of these values, it is much easier for other researchers to see which values are out there and to compare their own data to other studies.
The metabolism indicators also take into account energy, water and air pollution as well as urban characteristics indicators. With this big masterlist, it will therefore also become possible to identify indicators for resource use and pollution emission.
The final goal is to provide everyone in the community with the following tools:
- A centralised overview that makes it easy to explore a variety of studies with one single click
- Maps that can be navigated to see where studies have been done and what the outcome was
- A consistently formatted database with research data, which can be viewed online or downloaded in CSV format
- Data visualizations that present the dataset in an attractive, easy-to-understand way
- Perhaps the team’s own interesting insights after all this data has been mined!
To cite this dataset, please refer to https://doi.org/10.6084/m9.figshare.7326485.v1.
In 2019, Metabolism of Cities launched the successor of the Global Urban Metabolism Dataset called MultipliCity. MultipliCity is a user-friendly, centralised data platform for data on (urban) resource flows and stocks. Its primary features include:
- Academic rigor: all data points are linked to their original sources, data quality indicators are embedded, and an audit trail is available for each data point.
- Community-driven: any registered user can upload data for their city, following some simple guidelines and only basic training.
- User-friendly interface: the system is made with the general public in mind and data can be browsed, mapped, visualized, and downloaded by any user
- Replicable and scalable: data visualizations, analysis tools, and other features that are made available for one city can be used for any other city in the system. The system is built to scale and also tackle other spatial levels (regions, nations, islands etc.).
- Open source and open access: the source code is freely available and all data can be accessed without restrictions.
The short-term goal of the MultipliCity platform is to enable crowdsourcing of the groundwork and desktop research that is required for urban metabolism research. Any student, city official, or interested party can upload a dataset to the system. The quality is kept in check by registering data quality indicators as well as through support of data curators that review each dataset. Researchers can filter, compare, and download these datasets for their own research goals.
After completing the initial data loading stage, Metabolism of Cities plans to expand the system with a number of tools and utilities that assist analysis and interpretation of the datasets. Once a sufficiently large number of datasets from across the world has been loaded, tools and models can be embedded in MultipliCity to compare the resource (or economic) efficiency of infrastructure, to make recommendations around policy interventions, or to rank policies, indicators, or systems in particular cities by comparing them within other cities. A large number of future applications are possible when high-level data is available in a standardised format within a single system and the industrial ecology community is invited to collaborate in this endeavour.