Near Surface Soil Temperature Measurements At Resolute Bay, Northwest Territories

Abstract

D UKING the four summers of 1950-3 diamond drilling operations were undertaken at Resolute Bay, Cornwallis Island, for the purpose of installing temperature measuring equipment in the permanently frozen ground. Several recent papers have discussed various aspects of the project. Bremner (1955) described the actual drilling, analysed the difficulties encountered and made several recommendations based on that analysis for the possible assistance of others meeting similar drilling problems. Misener (1955) reported on heat flow in the crust basing his work on deep hole readings and on the examination of the thermal properties of core samples recovered at varying depths. Mise-ner, Bremner and Hodgson (1956) discussing the operation in general terms, combined information given by Bremner and Misener. However, apart from the general observations of Thomson and Bremner (1952), little of the temperature data itself has been reported upon. T h e present paper considers the near surface soil temperature data proper, and is based upon daily routine readings taken by officers of the Meteorological Division of the Canadian Department of Transport and the Dominion Observatory of the Department of Mines and Technical Surveys. The data have been supplemented by special studies undertaken by the writer during the three summers of 1953-5 and the winter of 1953-4. So little soil temperature data are available from permafrost regions in North America that the data are published now, without waiting for the more conventional long-term averages. T h e first part of the paper is concerned with routine near surface soil temperature readings from within the 6-foot overburden of frozen gravel and shattered rock overlying the limesto'ne bedrock. This depth is subject to daily fluctuations in temperature resulting from variations in surface weather above the soil. Monthly averages for the period 1951-5 are given for depths at 4, 8, 18, and 60 inches, and the five year averages shown. At other depths, where recording elements have been installed more recently, that is, at depths of 10,20, 25, and 35 inches, data for the two years 1954-5 have been considered. The second part of the paper is a preliminary report on a special study made in the fall of 1955 on the freeze-back in the active layer. Generalizations on' soil temperature and moisture content and migration are presented based on field data. Detailed studies of the interrelationships of climate and soil with the thermal regime will be published later.