Climate change affects various components of the polar environment, including lacustrine systems in many regions of the Antarctic Peninsula. However, the recent status of these life-preserving habitats remains poorly known. We performed field geomorphological mapping and limnological characterization of lakes distributed across Devil's Bay in the northern area of Vega Island, James Ross Archipelago, and described some significant changes in their physical and chemical properties during the 2013 summer season. Fifty lakes were described in the area, even though the area is relatively small (~12 km2). Six major lake types were distinguished based on their geomorphological settings and their origins, and their hydrochemical properties were compared with the neighbouring lake districts. The geomorphic characteristics of the lakes range from stable lakes on till plains (21 out of 50 lakes), to kettle lakes on fresh moraines with an unstable shoreline, to very dynamic ice-contact lakes with fluctuating water levels and inundated areas. The ice-contact lake dynamics were observed using ‘Lake Payer’ as an example. At the interface between hydrology and geosciences, this study provides new and original data from a yet largely unexplored region and emphasizes the importance of cross-disciplinary research in polar sciences.

Lentic freshwater habitats are important centres of biodiversity within the infrequent ice-free oases across Antarctica. Given imminent climate changes, it is crucial to catalogue these habitats in order to provide baseline data for future monitoring and biological surveys. The lacustrine systems of Clearwater Mesa, a previously unexplored part of James Ross Island, north-eastern Antarctic Peninsula, are described here. We conducted basic geomorphological and limnological surveys over three Antarctic summers (2009–16) to characterize landscape evolution, infer the origin of lake basins and assess the variability in their water chemistry. Stable shallow lakes, formed in depressions between lava tumuli following the last deglaciation, were found to dominate the volcanic mesa, although several peripheral lakes in ice-proximal settings appear to have formed recently as a result of post-Neoglacial ice recession. We found large heterogeneity in conductivity (~10–7000 μS cm−1), despite the lithologically uniform substrate. This variability was shown to be related to lake type, basin type (open vs closed), meltwater source and proximity to the coast. Inter-annual differences were attributed to changes in sea spray influx and snow accumulation driven by variable weather conditions. Overall, the ion composition of lakes suggested that sea spray was the dominant source of ions, followed by the weathering of bedrock.

This study describes the origin, bedrock geology, geomorphology, hydrological stability and physical and chemical characteristics of a representative set of 29 lakes in the ice-free parts of the Ulu Peninsula, James Ross Island, located close to the northern tip of the Antarctic Peninsula. Based on these features, six different types of lakes were defined: stable shallow lakes on higher-altitude levelled surfaces, shallow coastal lakes, stable lakes in old moraines, small unstable lakes in young moraines, deep cirque lakes and kettle lakes. We observed a significant relationship between lake type and water chemistry. Bedrock, lake age and morphometry together with altitude were the most important factors underlying the observed limnological variability. Our results further suggested possible nitrogen limitation in the lake ecosystems. However, physical factors such as low temperature and light were also likely to be limiting.