Peter Lynch (1947–)

Basic Facts

Full name: Peter Lynch
Born: 1947, Dublin, Ireland
Status: Living
Current position: Emeritus Professor, School of Mathematical Sciences, University College Dublin

Education

Year	Degree / Institution	Notes
1968	B.Sc. in Mathematical Science, University College Dublin
1969	M.Sc. in Mathematical Science, University College Dublin
1982	Ph.D., Trinity College Dublin	Thesis: “Planetary-scale Hydrodynamic Instability in the Atmosphere”; Advisors: Ray Bates (primary), Larry Crane (secondary)

Career

1971–2004: Met Eireann (Irish Meteorological Service). Rose to Head of Research and Training Division, then Deputy Director.
1990–2024: Honorary part-time lecturer, School of Mathematics, Trinity College Dublin.
2004–2011: Met Eireann Professor of Meteorology, School of Mathematical Sciences, University College Dublin.
2011–present: Emeritus Professor at UCD.

Major Scientific Contributions

Richardson’s Forecast Vindication (1992)

Lynch published “Richardson’s Barotropic Forecast: A Reappraisal” in the Bulletin of the American Meteorological Society (1992, Vol. 73, pp. 35–47). In this paper, Lynch showed that Lewis Fry Richardson’s famously “wrong” 1922 numerical forecast was not as fundamentally flawed as commonly believed. The enormous surface pressure tendency that Richardson computed (145 hPa in 6 hours) resulted primarily from un-initialized gravity-wave noise in the initial data, not from errors in Richardson’s method or equations. When the initial data are properly balanced (filtered to remove fast gravity waves), Richardson’s approach produces reasonable results. This paper rehabilitated Richardson’s reputation and demonstrated that his failure was one of initialization, not methodology.

Digital Filtering Initialization (1992 onwards)

Lynch developed the digital filter initialization (DFI) technique for numerical weather prediction. With Xiang-Yu Huang, he published “Initialization of the HIRLAM Model Using a Digital Filter” in the Monthly Weather Review (1992). The technique uses time-symmetric digital filters to remove high-frequency oscillations (gravity waves) from model initial conditions. DFI became widely adopted in operational NWP centers around the world as an efficient and practical initialization method.

He further refined the approach with the Dolph–Chebyshev window, published as “The Dolph-Chebyshev Window: A Simple Optimal Filter” in Monthly Weather Review (1997).

PHONIAC (2008)

With his son Owen Lynch (IBM Ireland, Dublin Software Laboratory), Peter Lynch recreated the landmark 1950 ENIAC weather forecasts on a Nokia 6300 mobile phone. They called the project PHONIAC – Portable Hand-Operated Numerical Integrator and Computer.

Technical details:

The Nokia 6300 ran at approximately 237 MHz with estimated capability of 237 MFLOPS
They converted a MATLAB program (eniac.m) into a Java application (phoniac.jar) for mobile execution
The 24-hour forecast computation took less than one second on the phone, compared to roughly 24 hours on the original ENIAC and about 30 milliseconds on a laptop
Results matched the recreated ENIAC predictions with maximum differences of only 0.01 meters

Lynch and Lynch noted that “the CRAY-1 and the Nokia 6300 are in the same league” regarding computational power, yet the phone consumed 1.5 W versus the CRAY-1’s 115 kW. Published in Weather (November 2008, Vol. 63, No. 11).

The Emergence of Numerical Weather Prediction: Richardson’s Dream (2006)

Lynch authored this comprehensive book (Cambridge University Press, 2006, ISBN 0521857291), which tells the story of Richardson’s trial forecast and the fulfillment of his dream of practical numerical weather forecasting. The book includes a complete reconstruction of Richardson’s forecast, detailed analysis of the causes of his failure, and the history of NWP from Richardson through the ENIAC computations to modern practice.

Popularization of NWP History

Lynch has been one of the foremost historians and popularizers of the story of numerical weather prediction. His writings about Richardson, the ENIAC forecasts, and the development of modern NWP have reached both scientific and general audiences. He also writes the mathematical recreational blog “That’s Maths” (associated with the Irish Times).

Awards and Honors

Member, Royal Irish Academy (2012)
European Meteorological Society Silver Medal (2014) – for “outstanding contribution to meteorological education and outreach”
Maths Week Ireland Award (2017) – for public mathematics awareness
Fellow, Institute of Physics
Fellow, Institute of Mathematics and its Applications

Other Books

Rambling Round Ireland: A Commodius Vicus of Recirculation (2016)
That’s Maths: The Mathematical Magic in Everyday Life (2020)
That’s Maths 2: A Further Medley of Mathematical Musings (2022)

Connections to Other Scientists

Lewis Fry Richardson: Lynch’s principal historical subject; spent decades studying and rehabilitating Richardson’s forecast.
Owen Lynch: Son and collaborator on the PHONIAC project.
Xiang-Yu Huang: Co-developer of digital filter initialization.
Ray Bates: PhD advisor at Trinity College Dublin.
George Platzman: Lynch built on Platzman’s 1979 historical paper about the ENIAC computations.
Jule Charney: Subject of Lynch’s historical research on the ENIAC period.

Key Publications

Lynch, P. (1992). “Richardson’s Barotropic Forecast: A Reappraisal.” Bulletin of the American Meteorological Society, 73(1), 35–47.
Lynch, P. & Huang, X.-Y. (1992). “Initialization of the HIRLAM Model Using a Digital Filter.” Monthly Weather Review, 120(6), 1019–1034.
Lynch, P. (1997). “The Dolph-Chebyshev Window: A Simple Optimal Filter.” Monthly Weather Review, 125(4), 655–660.
Lynch, P. (2006). The Emergence of Numerical Weather Prediction: Richardson’s Dream. Cambridge University Press.
Lynch, P. & Lynch, O. (2008). “Forecasts by PHONIAC.” Weather, 63(11), 324–326.

Sources

Accessed: 2026-04-02

Michał Brennek