The thermal regime of a sphagnum peat bog

In this study air and ground temperature measurements taken over a 3-year period in a virgin peat bog are compared with similar measurements taken at nearby mineral soil sites. The purpose of the study was to access the significance of temperature differences that can be expected due to terrain and soil thermal properties. The drainage of cold air into the peat bog was found to be the major factor causing minimum air temperatures to be lower over the bog than at nearby weather stations. The condition of the bog, i.e. whether it was wet or dry, thawing or snow-covered, appeared to have some effect on minimum air temperatures but was not as important a factor as air drainage. Monthly and annual average peat soil temperatures were several degrees colder than corresponding mineral soil temperatures. The peat soil temperatures were colder because heat available from radiation and convection was used for evaporation rather than for warming the soil.