| Summary: | application/pdf The temperatures of the air-layer near the ground，underground and snow-cover have been measured with resistance thermographs at Tsutsujiyama near Onneyu continuosly for more than three years since August 1972.Along with the analysis of the chart records， thirty areas where various periglacial phenomena are seen were studied with respect to their geology，topography，microtopography，ground temperature，vegetation， soil，microclimate，etc., to compare each other，and the data obtained were reported in the Memoirs. This report is a supplement to those already published， and also is a conclusive one on the mechanism of the formation of cold anomalies in the Kitami District， for which the writer has been studied for five years. The periglacial phenomena were classified into four groups ； （a）those occuring above 1700 m where the annual average temperature is below ?2℃ and the freezing index is more than 2000℃-day，where there are dwarf pine and alpine vegetations. Active permafrost，sorted polygons and rock-field on altiplanation terraces，nivation niches，solifluction lobes and stripes are observed ；（b）Those between 300?400 m and 1,000?1,300 m，＋4°?O℃，900?1,700. Former altiplanation terraces are observed at 1,150?1,300 m， 850?900 m， 720?750 m， and 530?650 m respectively. Frost-shattering and -cracking are pronounced at 300?400 m， on the foot of the hillslopes and along the former lake shore where welded tuff is exposed in most cases ；（c）Those below 300 m and ＋4℃，∠900 Verved clay，involutions，fossil ice-wedge in volcanic ash， turf hammocks and creeps. etc.，are observed ；（d）Ice-shove ridges along the beach of the Okhotsk Sea. The cold anomalies including sporadic permafrost within the area of（b）are formed mostly in frost-shattered and -clacked welded tuff（and rhyolite），where thick peat and/or moss cover works as an insulator and a damper for heat and air circulation. In the early winter， when the diurnal minimum reaches to ?10°??15℃，the cold air which flowed in through the natural or artificial opening cool the ...
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