Location The Larsemann Hills (69°24' S, 76°20' E) are a series of rocky peninsulas and islands, located midway between the eastern extent of the Amery ice shelf and the southern boundary of the Vestfold Hills, in Prydz Bay, East Antarctica. Occupying an area of 50 km2, the Larsemann Hills consist of two main peninsulas, Broknes to the east and Stornes to the west, as well as several off-shore islands. More than 150 freshwater lakes exist in the area, ranging from small ephemeral ponds to lakes exceeding 0.13 km2 (Lake Nella) and 38 m deep (Progress Lake).
Formation and diversity The lakes in Larsemann Hills are thought to have formed from the exposure of basins after the retreat of the continental ice cap or after isolation due to the isostatic uplift following deglaciation. The lakes are connected to the coast by steep-sided valleys that dissect the area. During the summer months these lakes are partially to fully ice free and are well mixed by the strong easterly katabatic winds, while during the winter they lie under ice covers —2 m thick. In general, the lakes on Stornes Peninsula have lower conductivities than those on Broknes Peninsula; these differences are believed to reflect the amount of freshwater input or the time elapsed since deglaciation. There is more snow cover on Stornes than Broknes Peninsula, which results in a cooler microclimate. Lake Reid (69°22' S, 76°23' E) on Broknes Peninsula is a relatively small (0.2 km2), shallow lake (4 m deep), which is seasonally stratified and brackish. During winter the lake becomes anoxic, acquiring oxygen after ice melt and mixing in summer.
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