Gerard de Geer - de Geer From A Modern Perspective

De Geer From A Modern Perspective

De Geer's most significant contribution to Quaternary science was unquestionably the identification of varves, and his recognition of their potential in establishing annual chronologies of past climatic and environmental change. The Swedish Time Scale was the most precise and accurate geological timescale of its day, and it is still being improved and added to today. His insistence that varves represented quantifiable proxies for past climate has since been borne out to a degree, but the relationship between varve thickness and hydrometeorological conditions is not as simple as he presumed. Varves have recently experienced a renaissance as methods and techniques of study have improved, and varves are now regularly used to calibrate radiocarbon timescales.

In many ways, De Geer's concerns mirror that of modern Quaternary geologists and palaeoclimatologists, particularly his recognition of the need for high-resolution natural archives of past change, and the importance of testing whether global change is synchronous. De Geer's principle failing was his faith in teleconnections, where his findings were clearly influenced by his preconceptions. His belief that variations in solar radiation were the principal agent of all climate change has also since been shown to be incorrect. Nevertheless, De Geer asked all the right questions, and his errors can be attributed as much to over-enthusiasm and a single-minded passion, as they can to bad science.