City Catalyst Open Source Helps Cities Start Their - Common Knowledge Scout

# CityCatalyst Open Source for City Climate Tracking > [! note]- > The content of this page is generated by audio/video transcription and text transformation from the content and links of this source. Source: [https://fosdem.org/2025/schedule/event/fosdem-2025-6099-citycatalyst-open-source-helps-cities-start-their-climate-journey/](https://fosdem.org/2025/schedule/event/fosdem-2025-6099-citycatalyst-open-source-helps-cities-start-their-climate-journey/) <video src="https://video.fosdem.org/2025/h2214/fosdem-2025-6099-citycatalyst-open-source-helps-cities-start-their-climate-journey.av1.webm" controls></video> ## Summary & Highlights: CityCatalyst is an open source web application designed to help cities manage their climate journeys by tracking greenhouse gas emissions across various sectors. It uses the GHG Protocol for Cities format to assemble emissions data from multiple sources, including AI models and satellite data. The platform aims to empower cities by providing a public dashboard for transparency and accountability, and it plans to include risk assessments and action planning in future versions. Built using a range of open source technologies, CityCatalyst is piloted in Brazil and seeks global expansion. **Introduction to CityCatalyst** CityCatalyst is an innovative open source tool developed by the Open Earth Foundation to assist cities in tracking and managing their greenhouse gas emissions. This application is crucial for cities to create comprehensive greenhouse gas inventories, which are necessary for effective climate action. **Importance of Greenhouse Gas Inventories** Greenhouse gas inventories are vital for cities to identify key emission sources and allocate resources effectively. By understanding their emissions, cities can target investments and policies to reduce their carbon footprint. These inventories are also essential for securing climate action funding. **Challenges and Solutions** Despite the importance of greenhouse gas inventories, only a small percentage of cities have them due to data accessibility and reliability challenges. CityCatalyst addresses these issues by providing a user-friendly platform that integrates various data sources and offers guided data input. **Technical Implementation** CityCatalyst is built using a combination of open source technologies, including React, NextJS, and PostgreSQL, among others. It features a global API for data access and a data pipeline for processing large datasets into the GHG Protocol standard. **Pilot Project in Brazil** The platform is being piloted in Brazil, where 50 cities are developing their first greenhouse gas inventories, climate action plans, and risk assessments. This pilot project aims to demonstrate the platform's effectiveness and scalability. **Contributing to CityCatalyst** CityCatalyst is an open source project, and contributions are welcome. Interested individuals can report bugs, propose features, or contribute code via GitHub. ## Importance for an eco-social transformation CityCatalyst plays a significant role in eco-social transformation by enabling cities to take control of their climate impact through accessible open source technology. It addresses sustainable issues by helping cities track and reduce their greenhouse gas emissions, thus promoting environmental responsibility. Socially, it fosters transparency and accountability by providing public dashboards for citizens. For eco-social designers, CityCatalyst offers a model for integrating diverse data sources into a cohesive platform, facilitating collaboration and innovation. Challenges include ensuring data accuracy and overcoming technical and political barriers to data sharing and implementation. The project also raises ethical considerations regarding data privacy and the equitable distribution of climate action resources. ## Slides: | | | | --- | --- | | ![[FOSDEM 2025/assets/CityCatalyst-Open-Source-Helps-Cities-Start-Their-/preview_001.jpg\|300]] | Evan Prodromou and Milan Gruner from the Open Earth Foundation present at FOSDEM on February 2, 2025, discussing their work on CityCatalyst. | ![[FOSDEM 2025/assets/CityCatalyst-Open-Source-Helps-Cities-Start-Their-/preview_002.jpg\|300]] | Evan Prodromou and Milan Gruner introduce themselves and the Open Earth Foundation, emphasizing their mission to use open source technology to combat climate change. | ![[FOSDEM 2025/assets/CityCatalyst-Open-Source-Helps-Cities-Start-Their-/preview_003.jpg\|300]] | CityCatalyst is introduced as a tool for creating greenhouse gas inventories for cities, highlighting its role in climate action. | ![[FOSDEM 2025/assets/CityCatalyst-Open-Source-Helps-Cities-Start-Their-/preview_004.jpg\|300]] | A greenhouse gas inventory is a comprehensive accounting of all greenhouse gases emitted within a city, organized by sector, gas, and scope, following the GHG Protocol for Cities. | ![[FOSDEM 2025/assets/CityCatalyst-Open-Source-Helps-Cities-Start-Their-/preview_005.jpg\|300]] | Tracking emissions is crucial for climate action, as it enables cities to act and secure investment. With cities responsible for 70% of global emissions, transparency and accountability are vital. | ![[FOSDEM 2025/assets/CityCatalyst-Open-Source-Helps-Cities-Start-Their-/preview_006.jpg\|300]] | Only 5% of cities have greenhouse gas inventories due to challenges in accessing reliable data for all sectors and ensuring personnel have the necessary skills. | ![[FOSDEM 2025/assets/CityCatalyst-Open-Source-Helps-Cities-Start-Their-/preview_007.jpg\|300]] | CityCatalyst offers a web application to facilitate the creation of greenhouse gas inventories, addressing data access and reliability challenges. | ![[FOSDEM 2025/assets/CityCatalyst-Open-Source-Helps-Cities-Start-Their-/preview_008.jpg\|300]] | CityCatalyst includes a global data warehouse to integrate diverse data sources, simplifying the process for cities to compile their inventories. | ![[FOSDEM 2025/assets/CityCatalyst-Open-Source-Helps-Cities-Start-Their-/preview_009.jpg\|300]] | The platform provides guided data input for locally-sourced data, helping cities overcome challenges in data collection and entry. | ![[FOSDEM 2025/assets/CityCatalyst-Open-Source-Helps-Cities-Start-Their-/preview_010.jpg\|300]] | CityCatalyst is built using various open source technologies, including React and NextJS, with a separate API for handling large data sources. | ![[FOSDEM 2025/assets/CityCatalyst-Open-Source-Helps-Cities-Start-Their-/preview_011.jpg\|300]] | In a pilot project in Brazil, 50 cities are developing climate inventories and action plans, with collaboration from local consultants to gather data. | ![[FOSDEM 2025/assets/CityCatalyst-Open-Source-Helps-Cities-Start-Their-/preview_012.jpg\|300]] | Contributions to CityCatalyst are encouraged, with opportunities to report issues, propose features, and contribute code via GitHub. | ![[FOSDEM 2025/assets/CityCatalyst-Open-Source-Helps-Cities-Start-Their-/preview_013.jpg\|300]] | The session concludes with a focus on CityCatalyst, presented by Evan Prodromou and Milan Gruner. ## Links [CityCatalyst Github Repository](https://github.com/Open-Earth-Foundation/CityCatalyst) [Video recording (AV1/WebM) - 49.7 MB](https://video.fosdem.org/2025/h2214/fosdem-2025-6099-citycatalyst-open-source-helps-cities-start-their-climate-journey.av1.webm) [Video recording (MP4) - 224.1 MB](https://video.fosdem.org/2025/h2214/fosdem-2025-6099-citycatalyst-open-source-helps-cities-start-their-climate-journey.av1.mp4) [Video recording subtitle file (VTT)](https://video.fosdem.org/2025/h2214/fosdem-2025-6099-citycatalyst-open-source-helps-cities-start-their-climate-journey.vtt) [Chat room(web)](https://fosdem.org/2025/chat/h2214) [Chat room(app)](https://fosdem.org/2025/chat/h2214/app) [Submit Feedback](https://fosdem.org/2025/feedback/)