Rennick Glacier (center point lat. 71° 15' S., long. 162° 30' E.) and its tributaries are currently receding. The grounding line is migrating inland (Reference Mayewski, Mayewski, Attig and Drewry.Mayewski and others, in press), and the area of local lakes and snow patches lias decreased.
Reference Skinner and RickerSkinner and Ricker (1968) observed that many small lakes in the Reeves Glacier area (center point lat. 74° 45' S., long. 162° 00' W.) were formerly as much as 0.3 m deeper. In the Rennick Glacier area lacustrine strandlines and algal peats show that the lakes were formerly more extensive. 14C dates from two samples of algal peats from 4 m and 2 m above current lake level are of 1 265 ± 130 B.P. (6x-4069) and 1 085 ±105 B.P. (6x-4068), respectively.
Reference Skinner and RickerSkinner and Ricker (1968) mention apparent decreases in the area of snowdrifts over the past century in the Reeves Glacier area. In the Rennick Glacier area, undated pro-talus ramparts stranded meters to tens of meters in front of snow-patches and snow ramps suggest similar decreases. Air photographs taken in 1962 and 1974 (Fig. 1) also show the decrease in snow cover on the walls of an easterly-facing bedrock embayment, west of Rennick Glacier. Similar examples exist elsewhere in the Rennick Glacier region.
The cause of this decrease in available moisture is unknown. However, monitoring of lakes and snow-patches may yield data on short-term climatic changes which will be of particular value when used in conjunction with other climatic data, such as the Holocene glacial record and ocean-bottom data.
Acknowledgement
This information was collected as part of a field program in nothern Victoria Land (1974-75) supported by U.S. National Science Foundation grant DPP 74-15210.