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Abstract Historical accounts suggest that Euro-American agricultural practices (post–1850 CE) accelerated soil erosion in the Paleozoic Plateau of the Upper Mississippi River Valley (USA). However, the magnitude of this change compared to longer-term Late Pleistocene rates is poorly constrained. Such context is necessary to assess how erosion rates under natural, high-magnitude climate and eco-geomorphic change compare against Euro-American agricultural erosion rates. We pair cosmogenic 10Be analyses and optically stimulated luminescence (OSL) ages from samples of alluvium to build a paleoerosion-rate chronology for Trout Creek in southeastern Minnesota (USA). Erosion rates and their associated integration periods are 0.069–0.073 mm yr−1 (32–20 ka), 0.049 mm yr−1 (28–14 ka), and 0.053 mm yr−1 (14–0 ka). Based on previous studies, we relate these rates to (1) the transition from forest to permafrost at the onset of the Last Glacial Maximum, (2) the decline of permafrost coupled with limited vegetation, and (3) climate warming and vegetation re-establishment. These pre-settlement erosion rates are 8× to 12× lower than Euro-American agricultural erosion rates previously quantified in the region. Despite a limited sample size, our observed rapid increase in erosion rates mirrors other sharply rising anthropogenic environmental impacts within the past several centuries. Our results demonstrate that agricultural erosion rates far exceed climate-induced erosion-rate magnitude and variability during the shift from the last glaciation into the Holocene. 

Abstract The Northern and Southern Patagonian Icefields are rapidly losing volume, with current volume loss rates greater than 20 km³a⁻¹. However, details of the spatial and temporal distribution of their volume loss remain uncertain. We evaluate the rate of 21st-century glacier volume loss using the hydrological balance of four glacierised Patagonian river basins. We isolate the streamflow contribution from changes in ice volume and evaluate whether the rate of volume loss has decreased, increased, or remained constant. Out of 11 glacierised sub-basins, seven exhibit significant increases in the rate of ice volume loss, with a 2006–2019 time integrated anomaly in the rate of glacier volume loss of 135 ± 50 km³. This anomaly in the rate of glacier-volume-loss is spatially heterogeneous, varying from a 7.06 ± 1.69 m a⁻¹increase in ice loss to a 3.18 ± 1.48 m a⁻¹decrease in ice loss. Greatest increases in the rate of ice loss are found in the early spring and late summer, suggesting a prolonging of the melt season. Our results highlight increasing, and in some cases accelerating, rates of volume loss of Patagonia's lake-terminating glaciers, with a 2006–2019 anomaly in the rate of glacier volume loss contributing an additional 0.027 ± 0.01 mm a⁻¹of global mean sea-level rise. 

Abstract. Determining the timing and extent of Quaternary glaciations around the globe is critical to understanding the drivers behind climate change and glacier fluctuations. Evidence from the southern mid-latitudes indicates that local glacial maxima preceded the global Last Glacial Maximum (LGM), implying that feedbacks in the climate system or ice dynamics played a role beyond the underlying orbital forcings. To shed light on these processes, we investigated the glacial landforms shaped and deposited by the Lago Argentino glacier (50° S), an outlet lobe of the former Patagonian Ice Sheet, in southern Argentina. We mapped geomorphological features on the landscape and dated moraine boulders and outwash sediments using 10Be cosmogenic nuclides and feldspar infrared stimulated luminescence (IRSL) to constrain the chronology of glacial advance and retreat. We report that the Lago Argentino glacier lobe reached more extensive limits prior to the global LGM, advancing during the middle to late Pleistocene between 243–132 ka and during Marine Isotope Stage 3 (MIS 3), culminating at 44.5 ± 8.0 and at 36.6 ± 1.0 ka. Our results indicate that the most extensive advance of the last glacial cycle occurred during MIS 3, and we hypothesize that this was a result of longer and colder winters, as well as increased precipitation delivered by a latitudinal migration of the Southern Westerly Winds belt, highlighting the role of local and regional climate feedbacks in modulating ice mass changes in the southern mid-latitudes.