Julien Pierret
Active contribution

Climate Research to iCHARM

A long-running climate-data story spanning computational statistics, distributed processing, browser visualization, and a living institutional platform.

2012–present · Researcher, original application author, backend contributor, and mentor
ModelingResearchData EngineeringWeb Development
Visit project View source Dissertation Historical climate site
iCHARM interactive globe showing global surface temperatures and atmospheric streamlines
Contribution boundary

I created the original JavaScript climate site and the Angular 4DVD application. The current iCHARM platform reuses substantial 4DVD logic; I contribute backend and parsing work and provide architectural guidance and mentorship, but the current frontend and broader platform are collaborative work.

At a glance

The project began with a practical research question: how can large, high-dimensional climate datasets be analyzed and explored without forcing every user to operate specialist scientific software?

My Ph.D. work connected two systems problems. The statistical side used spherical harmonics, numerical methods, and distributed Spark computation to derive and interpolate global climate fields. The delivery side used a database, web server, JavaScript, and WebGL to make large climate datasets interactive in a browser.

Evolution

Statistical research

The research required stable numerical implementations, distributed processing, and a way to reason about global fields on a sphere. It became the foundation for the open-source mrsharky repository and two publications.

Original JavaScript visualization

I built https://climate.mrsharky.com as an early browser-based interface for exploring the research outputs. It demonstrated that substantial visualization work could move into the browser while the server focused on preparing and delivering the right data.

4DVD

The next generation was an Angular application documented in my dissertation. It joined database storage, server-side delivery, JavaScript, and WebGL into a more complete system for visualizing large reanalysis datasets. It is still hosted at SDSU at https://4dvd.sdsu.edu

iCHARM

iCHARM continues that lineage as an evolving institutional platform. It reuses substantial logic from 4DVD and is expanding beyond gridded climate datasets into station data, shapefiles, and additional scientific formats. My current work focuses on backend behavior, data parsing, architecture, cleanup, and student mentorship.

Technical decisions

  • Explain the domain problem before introducing the mathematics.
  • Move interactive visualization into the browser while keeping data delivery bounded and reproducible.
  • Use distributed computation when the numerical workload exceeds a single machine.
  • Treat scientific file formats and metadata as product concerns rather than incidental preprocessing details.

Results and lessons

The most important result is continuity: research code became a working web system, that system became a dissertation artifact, and its logic continues to support a platform maintained and extended by collaborators and students.