Elizabeth Cicely Ridley (née Taylor, September 26, 1927 – December 23, 2008) was a British-American applied mathematician known for her work in numerical

quantum chemistry Quantum chemistry, also called molecular quantum mechanics, is a branch of physical chemistry focused on the application of quantum mechanics to chemical systems, particularly towards the quantum-mechanical calculation of electronic contributions ...

and in

climate model Numerical climate models use quantitative methods to simulate the interactions of the important drivers of climate, including atmosphere, oceans, land surface and ice. They are used for a variety of purposes from study of the dynamics of the cl ...

ing. The Roble–Dickinson–Ridley code that she and her collaborators created at the

National Center for Atmospheric Research The US National Center for Atmospheric Research (NCAR ) is a US federally funded research and development center (FFRDC) managed by the nonprofit University Corporation for Atmospheric Research (UCAR) and funded by the National Science Foundatio ...

was the first

general circulation model A general circulation model (GCM) is a type of climate model. It employs a mathematical model of the general circulation of a planetary atmosphere or ocean. It uses the Navier–Stokes equations on a rotating sphere with thermodynamic terms f ...

of the

thermosphere The thermosphere is the layer in the Earth's atmosphere directly above the mesosphere and below the exosphere. Within this layer of the atmosphere, ultraviolet radiation causes photoionization/photodissociation of molecules, creating ions; the ...

Life

Ridley was born in

Leicester Leicester ( ) is a city status in the United Kingdom, city, Unitary authorities of England, unitary authority and the county town of Leicestershire in the East Midlands of England. It is the largest settlement in the East Midlands. The city l ...

on September 26, 1927, the older of two sisters. She became head girl at the Wyggeston Grammar School for Girls, now incorporated into

Regent College, Leicester Regent College was a sixth form college in Leicester, England. The college was formed in 1976 as the ''Wyggeston Collegiate Sixth Form College'' and was renamed ''Regent College'' in 1996. It was merged into the nearby Wyggeston and Queen El ...

, and went up to

Newnham College, Cambridge Newnham College is a women's Colleges of the University of Cambridge, constituent college of the University of Cambridge. The college was founded in 1871 by a group organising Lectures for Ladies, members of which included philosopher Henry Sid ...

on a scholarship in 1947. She earned a master's degree in physics in 1951, with first-class honours, in 1951, and remained at Cambridge as a doctoral student of

Douglas Hartree Douglas Rayner Hartree (27 March 1897 – 12 February 1958) was an English mathematician and physicist most famous for the development of numerical analysis and its application to the Hartree–Fock equations of atomic physics and the c ...

, completing her Ph.D. in 1955. Her dissertation was ''Some Studies of Atomic Structure''. After finishing her doctorate, she became a researcher at the

United Kingdom Atomic Energy Authority The United Kingdom Atomic Energy Authority is a UK government research organisation responsible for the development of fusion energy. It is an executive non-departmental public body of the Department for Business, Energy and Industrial Strategy ...

, at what is now the

Harwell Science and Innovation Campus The Harwell Science and Innovation Campus is a 700-acre science and technology campus in Oxfordshire, England. Over 6,000 people work there in over 240 public and private sector organisations, working across sectors including Space, Clean Ener ...

; her work there involved computing the

electron configuration In atomic physics and quantum chemistry, the electron configuration is the distribution of electrons of an atom or molecule (or other physical structure) in atomic or molecular orbitals. For example, the electron configuration of the neon atom ...

uranium Uranium is a chemical element with the symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium is weak ...

, and applied mathematician John P. Boyd has called her "a pathfinder in numerical quantum chemistry" for this work. Her husband, Brian Ward Ridley, also came to work at Harwell; they had four children beginning in 1957, and Ridley retired from her work in 1958 to become a housewife. In 1964, Ridley and her family moved to Colorado, following her husband, who became a professor of physics at the

University of Colorado The University of Colorado (CU) is a system of public universities in Colorado. It consists of four institutions: University of Colorado Boulder, University of Colorado Colorado Springs, University of Colorado Denver, and the University of Co ...

. She joined the

in 1968, working for them on computer codes for

ing of both the Earth and Venus. Before 1972, when Margaret Anne LeMone joined NCAR, she was one of only three doctoral-level women researchers at NCAR, together with

Joan Feynman Joan Feynman (March 31, 1927 – July 21, 2020) was an American astrophysicist. She made contributions to the study of solar wind particles and fields, sun-Earth relations, and magnetospheric physics. In particular, Feynman was known for develop ...

and Sue Anne Bowling. It was in her work at NCAR that Ridley created the Roble–Dickinson–Ridley code for general circulation modeling of the thermosphere. She retired in 1995, and died in

Louisville, Colorado The City of Louisville () is a home rule municipality located in southeastern Boulder County, Colorado, United States. The city population was 21,226 at the 2020 United States Census. Louisville began as a mining community in 1877, experienced a ...

on December 23, 2008.

Selected publications

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References

{{DEFAULTSORT:Ridley, Cicely 1927 births 2008 deaths 20th-century American mathematicians 20th-century British mathematicians American women mathematicians British women mathematicians Applied mathematicians American climatologists British climatologists People from Leicester Women climatologists 20th-century American women 21st-century American women