Purpose
The LCA Commons API provides public access to life cycle data for research and analysis in various fields including agriculture, energy, transportation, construction, and defense. The API guide is designed to help users, whether new to the API, developers, or researchers, retrieve datasets, access group and repository information, and utilize LCA Commons' resources through easy-to-use API calls. It provides clear instructions on how to interact with the public API, allowing seamless integration of LCA data into applications and research tools. By following this guide, users will understand how to access various types of public data, enabling them to gather information for use in their projects, research, or analyses.
Key Concepts
The LCA Commons API allows for the retrieval of publicly available life cycle data, metadata about groups, and repositories. Understanding these core concepts will help you effectively use the API.
Public API:
A set of methods that allow unrestricted access to public datasets and metadata. Unlike private APIs, public APIs don't require authentication, making them easier to access by any user without the need for a login.
Dataset:
A dataset in the context of LCA refers to a structured collection of data that quantifies various environmental aspects, such as carbon emissions, resource usage, and waste generation, for a specific product, process, or system. Datasets often represent inputs and outputs across the life cycle of a product, allowing researchers and practitioners to assess its environmental impact.
Repository:
Repositories in the LCA Commons API are digital locations where datasets are stored. A repository can hold multiple datasets and often includes metadata, such as when the datasets were created, the group that owns them, and the purpose of the data. Repositories are used to organize datasets by theme or project, such as "Energy Use Data" or "Agricultural Emissions."
Group:
A group in LCA Commons refers to a collection of repositories and datasets that are associated with a specific team, project, or organization. Public groups contain datasets that are available for anyone to access, allowing for broader data sharing and collaboration.
GET Method:
The HTTP GET method is used to request and retrieve data from the server. In the context of the public API, GET requests are used to access datasets, repository information, and group details without modifying any data.
Metadata:
Metadata refers to "data about data." In this API, metadata includes information like dataset names, descriptions, creation dates, and ownership details. It helps users understand the context and scope of the dataset without needing to download or access the entire dataset.
JSON (JavaScript Object Notation):
A lightweight data format used for storing and transporting structured data. JSON is easy to read and write for both humans and machines, and it is the standard format used in the LCA Commons API for data exchange.
JSON-LD (JSON for Linked Data):
JSON-LD is an extension of the JSON format, designed specifically for representing linked data. It allows datasets to be structured in a way that links related data points across the web, making the data more compatible and accessible for analysis. For the LCA Commons, JSON-LD is used to provide more meaningful and relevant representations of environmental data, which can be leveraged for better data integration and more complex queries.
For example, when users prepare to download repositories in JSON-LD format, they are getting data structured to enable comprehensive, linked insights that can be used in complex life cycle assessments or aggregated with other datasets.
The API also uses version-controlled schemas to ensure consistency and compatibility when retrieving data in JSON-LD format. The current openLCA schema version (v2.0), https://greendelta.github.io/olca-schema/intro.html, defines the structure of Life Cycle Assessment data provided by the LCA Commons.
Data Element Descriptions:
The API allows access to several types of LCA data, including:
- ModelType: Represents the classification of data such as ACTOR, CATEGORY, FLOW, and PROCESS.
- FlowType: Describes the nature of data flows to include ELEMENTARY_FLOW and PRODUCT_FLOW.
- ProcessType: Provides information about the type of processes, such as UNIT_PROCESS and LCI_RESULT. These elements help users structure queries and better understand the LCA datasets available in the Commons.