Year: 2026
Type: article
Abstract: Climate change is driving the rapid retreat of glaciers across the sub-Antarctic zone. Using continuous lake sediment-based records of past glacier changes, the recent trends can be evaluated in a long-term context. Here, we analyse sediments from two glacier-fed lakes: Lake Athéna II and Lake Héra, located downstream the Chamonix Glacier on the sub-Antarctic Kerguelen Islands in the Indian Southern Ocean. Lake Héra is a threshold lake for the adjacent outlet glacier: the Agassiz Glacier, but has been solely receiving meltwater runoff from the Chamonix Glacier since the Agassiz Glacier retreated from its maximum extent. Based on distinct changes in grain-size and sediment density, we argue this transition occurred around 495 CE. After this, the glaciogenic sediments in both lakes are solely derived from the Chamonix Glacier. By tracking multi-decadal to centennial changes in incoming clastic sediments, we suggest the Chamonix Glacier retreated close to its current extent between 600 and 750 CE, primarily advanced between 750 and 1600 CE, before gradually retreating towards present-day. The glacier trends documented here are in line with mean annual air temperature and sea surface temperature records that indicate colder late Holocene temperatures, reflecting a negative Southern Annular Mode-like state in the Indian Southern Ocean. Conversely, phases of more positive Southern Annular Mode-like conditions, including gradually more positive anomalies after ∼1600 CE and until present-day, are in line with a decrease in activity at the Chamonix Glacier.
Source: Frontiers in Earth Science
Language: English
Subfield: Atmospheric Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
SDG: Climate action
Open Access status: gold
Estimated APC paid: $3,801
OpenAlex ID: W7216395345