I worked for many years on Greenland problems, mainly dealing with the Greenland ice sheet, but I am now increasingly interested by problems of global glaciology. Perhaps I should say "re-interested" as I helped to prepare Fluctuations of Glaciers Volume III (1977) and I edited the proceedings of the Riederalp workshop on World Glacier Inventory (1980).
After arriving at the University of Manchester in 1994, I finished off several papers on Greenland glaciology and then I switched to global glaciology, with an emphasis on glacier-climate modelling. Although I was an early worker in the field of energy balance modelling, I did not consider this sort of model as very suitable for modelling global glaciology and I preferred to use, and extend, the degree-day model that I developed and tested during my Greenland work. For the application of the degree-day model, I have had to look carefully at the characteristics of observed mass balance series that are well documnents in successive volumes of Fluctuations of Glacier.