Algorithm Theoretical Basis Documents (ATBDs) describe the physical theory, mathematical procedures, and assumptions made for developing scientific algorithms that convert radiances received by remote sensing instruments into geophysical quantities. As such, they are the foundation of the thousands of Earth science data products available without restriction from NASA's Earth Science Data Systems (ESDS) Program.
The Algorithm Publication Tool (APT) revolutionizes the process of crafting ATBDs by offering a cloud-based platform designed with the user in mind. The APT standardizes the ATBD format and content and simplifies the authoring process while creating a centralized repository for the scientific community to access these crucial documents.
Historically, the absence of standardized ATBD formats and a centralized storage repository posed significant challenges to finding and using ATBDs. Documents lacked searchability and version updates were difficult to implement.
The primary APT development group operates within NASA's Interagency Implementation and Advanced Concepts Team (IMPACT), which is located at NASA's Marshall Space Flight Center in Huntsville, AL, and is an ESDS component. APT team members collaborated with Development Seed to construct and refine tool features.
"I think the APT is a very good system for making ATBDs consistent, organized, and citable," said Dr. Heesung Chong, lead data product developer for NASA's Tropospheric Emissions: Monitoring of Pollution (TEMPO) mission. "Specifically, we have six different TEMPO algorithms to describe. If we had to organize ATBD sections and do the formatting ourselves, the work would be far less efficient. The APT benefits not only the [data product] authors but also the TEMPO user community, who will read and cite the documents."
APT Components
The APT has three important parts: the authoring environment, the public user interface, and the governance dashboard.
Authoring Environment
The authoring environment enables approved ATBD authors to add content into the user interface and collaborate with co-authors. In response to user feedback, the platform now features template options compatible with popular tools such as Google Docs, Microsoft Word, and LaTeX. This capability ensures that users can collaboratively write documents offline in a familiar tool using the latest features in document authoring.
Upon completion, the user uploads the ATBD to the platform for review. All users have the option of using the APT user interface for document development, which allows them to collaborate with colleagues to write, edit, review, and publish an ATBD or use the templates. The availability of templates further enhances flexibility and ease of use.
"The ATBD template provided by [the] APT sets a good standard for documenting algorithm theoretical basis documents, which ensures clarity, reproducibility, and transparency in algorithm development," said Ankur Kumar, a graduate research assistant supporting NASA's Commercial Smallsat Data Acquisition (CSDA) program. "Its structured approach and detailed sections make it an invaluable resource for both developers and users, fostering trust and advancing scientific research."
Public User Interface
The public user interface contains published ATBDs that are human and machine searchable and readable. The search function uses both the ATBD identifying metadata and the ATBD content. ATBDs are available in both HTML and PDF formats for easy access and download.
Governance Dashboard
The governance dashboard enables the APT curator to monitor authorized user activities and to access tool metrics and ATBD information.
Additional Features
Several APT key features streamline and simplify the ATBD development process. The LaTeX equation editor enables users to insert and preview both inline and block equations while the BibTeX citation manager expedites citation formatting. The rich text editor further enhances authoring capabilities by enabling authors to easily insert tables, figures, references, and equations.
In addition, the APT facilitates submissions to the American Geophysical Union's Earth and Space Science journal. "It's a big advantage that authors can submit their ATBDs to the Earth and Space Science journal through [the] APT," said Chong.
APT Current Use
Active users from projects including the TEMPO mission; CSDA; NASA's Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission; and NASA's Ocean Biology Processing Group (OBPG) contribute valuable feedback that is leading to future APT improvements. Dr. Guoqing Wang, a research scientist from OBPG, for example, commended the user interface and template, stating that it "effectively covers the most important aspects of an ATBD and ensures consistency among them."
Currently, the APT repository hosts five publicly available ATBDs. Eighteen ATBDs are in development, with 13 in progress within the user interface and 5 using the template approach. With the APT at their disposal, scientists can now navigate the ATBD development process with efficiency and precision, promoting open science by fostering collaboration and transparency.
