© 1968 by Institute of Chartered Foresters
Climatic Zonation in the British Isles
The paper is the outcome of the decision to revise two earlier publications on climatic zonation in Scotland and in England and Wales. The recent publication by the Meteorological Office of averages of temperature in degrees Celsius for 1931–60, and the publication in 1967, by the Ordnance Survey, of rainfall maps for the period 1916–50, allowed up-to-date meteorological statistics to be used. The paper follows the procedure adopted in the two previous publications of using the length in days of the growing season (vegetative period). A map was produced of the actual lengths of the growing season for over 240 meteorological stations in Great Britain and Ireland. The climatic zonation was achieved by joining with lines those stations with equal lengths of growing seasons in days, based on average onthly temperatures reduced to sea level; seven temperature zones were then selected. The resulting temperature zonation was next superimposed on a rainfall map of the British Isles in which four zones of rainfall were chosen. The resulting boundaries of the combined temperature-rainfall zones were adjusted to give acceptable boundaries, where possible related to natural or artificial features on the ground giving altogether thirty-two subzones.