G.S. Callendar Archive

Scope and Content

The collection contains 102 notebooks (1936-1964) and documents containing data, charts, notes, readings and formulae concerning temperature and climate as far back as 1751 and in locations across the world; letters, reviews and many candid insights into the state of climate science between 1936 and 1964.

Box 8 contains the Family Collection. This includes photographs, personal correspondence, reprints, historical reappraisals, biographical material (some relating to Callendar's father - physics Professor H.L. Callendar); and papers relating to Callendar's war work, including FIDO (Fog Investigation Dispersal Operation), 1942-1946, and to his time with the Armament Design Establishment, 1950-1956. Also included are letters concerning the administration of the archive collection.

Administrative / Biographical History

In the first half of the twentieth century, the carbon dioxide theory of climate change had fallen out of favour with climatologists. Beginning in 1938, Guy Stewart Callendar (1898-1964), a noted steam engineer and amateur meteorologist, revived this theory by arguing that rising global temperatures and increased coal burning were closely linked. Working from his home in West Sussex, England, Callendar collected weather data from frontier stations around the world, formulated a coherent theory of infrared absorption by trace gases, and demonstrated that the carbon dioxide content of the atmosphere, like the temperature, was indeed rising.

Noting an upward trend in temperatures for the first four decades of the twentieth century, Callendar combined these results with studies of the retreat of glaciers, measurements of rising concentrations of atmospheric carbon dioxide since pre-industrial times, and information newly available concerning the infrared absorption bands of atmospheric constituents. He concluded that the trend toward higher temperatures was significant, especially north of the forty-fifth parallel; that increased use of fossil fuels had caused a rise of the concentration of carbon dioxide in the atmosphere of about ten percent from nineteenth century levels; and that increased sky radiation from the extra carbon dioxide was linked to the rising temperature trend.

Although he was an amateur meteorologist, Callendar worked on a truly global scale, compiling a reliable world data set of surface temperatures from earliest times and insisting - long before it became fashionable to do so - that climatology must deal with physics and atmospheric dynamics. Even in the depths of World War II, Callendar remained active in climate research, publishing two papers while working on technical problems (including infrared absorption) with the Ministry of Supply. In 1944 climatologist Gordon Manley noted Callendar's valuable contributions to the study of climatic change. A decade later, Gilbert Plass and Charles Keeling consulted with Callendar as they began their research programs. Just before the beginning of the International Geophysical Year in 1957, Hans Seuss and Roger Revelle referred to the 'Callendar effect' - defined as climatic change brought about by anthropogenic increases in the concentration of atmospheric carbon dioxide, primarily through the processes of combustion.


  • Box 1 Correspondence, maps, graphs and data, 1751-1964
  • Box 2-7 Notebooks, 1936-1964
  • Box 8 Family Collection, 1930-2003
  • Box 9 Notebooks, 1940-1959

Access Information

The digitised collection is open for consultation in the Archives Department by appointment during the Archives advertised opening hours. The paper collection is CLOSED.

Acquisition Information

On 19th March 2007 the collection was transferred to the UEA Library Archives.

Other Finding Aids

9 CD-Roms accompany the collection. They include digitised contents lists.

Physical Characteristics and/or Technical Requirements

The collection is contained in 9 boxes. Each box is accompanied by a CD-Rom containing scanned images of the contents.

Archivist's Note


Conditions Governing Use

Reproductions can be supplied in hard copy or digital format subject to physical condition and the terms of deposit. A charge is made for this service. Copyright restrictions may apply and the advice of the Archives department should be sought for any use of reproductions other than personal research.

Custodial History

After the death of G.S. Callendar in 1964, his two daughters (Miss Anne Callendar and Mrs Bridget Khan), gathered together his papers and notebooks and offered them, into temporary care, to Dr Derek Schove of St David's College, Kent. On the death of Dr Schove in January 1986 the collection was passed to the Royal Meteorological Society. A suitable home was later found for it at the Climatic Research Unit (CRU), University of East Anglia (UEA) where it was deposited in January 1989.

In 2002 and 2003 the papers were loaned to James Rodger Fleming and Jason Thomas Fleming who compiled, arranged, edited and scanned the collection. This work was supported by grants from the National Science Foundation and Colby College, Maine, USA.

Additional correspondence and family papers were added directly as 'Papers of G.S. Callendar. Callendar Family Collection Box 8' by Bridget Kahn on 8th July 2004. This box was scanned separately.

The seven notebooks contained in Box 9 were a later addition which had come to light in CRU. They were digitised by James Fleming and Sophie Swetz and deposited in 2016.


See archival history.