PeopleofSuperintelligence

Researcher

Christian A. Gueymard

Also known as Christian Gueymard

Christian Gueymard is a solar-radiation researcher whose work includes clear-sky models and machine-learning methods for separating direct and diffuse sunlight. He earned a doctorate at the University of Montreal and joined the Cité Écologique in 1986. SMARTS development began in the early 1990s, and his 1994 study examined atmospheric water and turbidity across Canada and the northern United States. He published the REST2 model in 2008 for cloudless-sky irradiance, and coauthored a gradient-boosting study in 2017 and a neural-network comparison in 2025. As of October 2026, he is President of Solar Consulting Services.

Now at
Solar Consulting Services

Timeline

  1. By 1986

    A doctorate in Montreal

    He earns a doctorate at the University of Montreal and joins the Cité Écologique in 1986.

  2. 1990s

    Developing the SMARTS model

    SMARTS is his spectral radiation model for predicting shortwave solar irradiance with high spectral resolution under variable atmospheric conditions; its development begins in the early 1990s.

  3. 1994

    A Canadian turbidity study

    In 1994, he publishes a study of monthly average atmospheric precipitable water and turbidity in Canada and the northern United States.

  4. 2008

    The REST2 radiation model

    In 2008, he publishes REST2, a high-performance model for cloudless-sky irradiance, illuminance, and photosynthetically active radiation.

  5. 2012

    A solar-resource keynote

    In 2012, he is invited to deliver a keynote presentation on solar-resource assessment at the World Renewable Energy Forum in Denver.

  6. July 2017

    Gradient boosting for irradiance

    In July 2017, he coauthors a study that uses gradient boosting to improve the separation of direct and diffuse solar-radiation components from one-minute global horizontal irradiance.

  7. 2025

    Neural networks for separation

    In 2025, he coauthors a comparison of conventional separation models and simple artificial neural networks for global solar irradiance components.

  8. As of October 2026

    President of Solar Consulting Services

    As of October 2026, he is President of Solar Consulting Services.

Career

  1. NowSolar Consulting ServicesPresident
  2. From 1986Cité Écologique

Education

  1. Université de MontréalDoctorate

From the biography.

  1. The median h-index is 48 at universities and 14 at frontier AI labsIncludes Université de Montréal. The median h-index is 48 at universities and 14 at frontier AI labs. We compare publishing careers, recent citations, dual appointments and job moves across 2,420 university researchers and 308 frontier-lab researchers.
  2. 20% of people at companies who shape AI also hold a university role, led by Google and Stanford UniversityIncludes Université de Montréal. We estimate that 539 of the 6,766 people with a known current organization (8%) hold both a university role and a company role, including 20% of people at companies and 13% of people at universities.
  3. Of 943 people shaping AI who worked at Google, 446 work there nowIncludes Université de Montréal. Our estimates of where the 943 people shaping AI who worked at Google and Google DeepMind work now: 446 at Google and 452 across 278 other organizations.
  4. The Massachusetts Institute of Technology trained or employed 44 of the 187 AI major-prize winners, more than any other universityIncludes Université de Montréal. The Massachusetts Institute of Technology trained or employed 44 of the 187 AI major-prize winners, more than any other university. We compare doctorate and 5+ year employment links, career timing and current workplaces for 187 major-prize and 1,111 best-paper winners.

Sources and credits

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  1. Intervenants | Intervenants – C.A.P. Éco-Communautaire capecocommunautaire.org. Checked 22 October 2026.
  2. About | Solar Consulting Services solarconsultingservices.com. Checked 22 October 2026.
  3. Analysis of monthly average atmospheric precipitable water and turbidity in Canada and Northern United States stars.library.ucf.edu. Checked 22 October 2026.
  4. GitHub - NatLabRockies/rest2: REST2 is the High-performance solar radiation model for cloudless-sky irradiance, illuminance, and photosynthetically active radiation github.com. Checked 22 October 2026.
  5. Improving the separation of direct and diffuse solar radiation components using machine learning by gradient boosting researchportal.uc3m.es. Checked 22 October 2026.
  6. Comparison of conventional and simple artificial neural network models for high-performance separation of global solar irradiance components at minutely resolution riuma.uma.es. Checked 22 October 2026.
  7. Contact Us | Solar Consulting Services solarconsultingservices.com. Checked 22 October 2026.