Some Features of the Summer Climate of Interior Alaska

A comparative analysis is made of the distribution of long term monthly mean temperature and precipitation data for three representative locations in the Alaska interior basin. Examples of extreme monthly conditions over the region are selected by reference to the record at Tanana dating back to 1903. The characteristics are outlined of the mean monthly orientations of the 700-millibar troughs and ridges and also the patterns of geopotential anomaly associated with summer months which exhibit extremes of warmth, cold, moisture and dryness. A comparison is made between these patterns and those that have been postulated for the time of the maximum Wisconsin glaciation

Aspects of Winter Temperatures in Interior Alaska

The interior basin between the climatic divides of the Brooks and Alaska Ranges has extremely low winter temperatures in contrast to the milder regime of both southcentral Alaska and the region on the Arctic Slope of the Brooks Range. There is a cold pole centered on the Yukon flats and extending over the Yukon and Tanana valleys. Two local factors in the occurrence of low winter temperatures are the wide expanse of relatively flat and low-lying surface suited to the development of substantial low level temperature inversions in winter when the radiation balance of the surface is strongly negative; and encirclement by a mountain mass which is effective in preventing the weaker low level synoptic scale weather systems from invading the basin. Large-scale circulation factors associated with extreme years are described.Aspects des températures hivernales en Alaska intérieur. L'auteur décrit les variations des températures mensuelles moyennes hivernales des vallées du Yukon et de la Tanana, en relation avec la topographie de la région. Il identifie les mois de froid extrême et de chaleur extrême à partir des observations recueillies en 66 ans. Pour ces mois extrêmes, les variations thermiques au jour le jour aux différentes stations révèlent l'influence des barrières topographiques sur les tendances au réchauffement. L'auteur décrit enfin les facteurs de circulation à grande échelle qui sont associés aux années extrêmes

Some Observations of Alaskan Glacier Winds in Midsummer

Discusses 21 June-12 July observations at Castner Glacier in the Alaska Range and 16 July-11 Aug 1967 at Worthington Glacier in the Chugach Range. The purpose was to study the frequency and diurnal variation of glacier winds and differences due to location and exposure. In both cases max windspeed occurs slightly before sunrise and in the mid-afternoon. In the absence of a daytime glacier wind at Castner, a regular night downslope circulation is often observed.Quelques observations sur les vents de glacier de l'Alaska au milieu de l'été. Les auteurs dévrivent les caractères des vents de glacier observés au milieu de l'été pour les glaciers Worthington et Castner. Chacun présente un double maximum quotidien de vélocité, soit juste avant l'aurore et vers le milieu de l'après-midi. Lorsqu'il n'y a pas de vent de glacier diurne à Castner, on observe souvent une circulation nocturne très régulière et descendante