Browsing by Author "Davies, Bethan J."

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    Accelerating Glacier Area Loss Across the Andes Since the Little Ice Age
    (John Wiley & Sons, 2024) Carrivick, Jonathan L.; Davies, Morwenna; Wilson, Ryan; Davies, Bethan J.; Gribbin, Tom; King, Owen; Rabatel, Antoine; García B., Juan Luis; Ely, Jeremy C.
    Andean glaciers are losing mass rapidly but a centennial-scale context to those rates is lacking. Here we show the extent of >5,500 glaciers during the Little Ice Age chronozone (LIA; c. 1,400 to c. 1,850) and compute an overall area change of -25% from then to year 2000 at an average rate of -36.5 km(2 )yr(-1) or -0.11% yr(-1). Glaciers in the Tropical Andes (Peru, Bolivia) have depleted the most; median -56% of LIA area, and the fastest; median -0.16% yr(-1). Up to 10 x acceleration in glacier area loss has occurred in Tropical mountain sub-regions comparing LIA to 2,000 rates to post-2000 rates. Regional climate controls inter-regional variability, whereas local factors affect intra-region glacier response time. Analyzing glacier area change by river basins and by protected areas leads us to suggest that conservation and environmental management strategies should be re-visited as proglacial areas expand.
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    Glacial geomorphology of the former Patagonian Ice Sheet (44-46 °S)
    (2021) Cooper, Emma-Louise; Thorndycraft, Varyl R.; Davies, Bethan J.; Palmer, Adrian P.; Garcia, Juan-Luis
    We map the glacial geomorphology of the former Patagonian Ice Sheet between 44 degrees S and 46 degrees S. Building on previous work, our map covers a similar to 50,000 km(2) region of west-central Patagonia. The study area includes the eastward-flowing Rio Pico, Rio Caceres, Rio Cisnes, Lago Plata-Fontana, El Toqui, Lago Coyt/Rio Nirehuao, Simpson/Paso Coyhaique, and Balmaceda palaeo-outlet glaciers, adjacent valleys, and the Andean Cordillera. The inventory contains >70,000 individual landforms mapped from remotely-sensed imagery and field surveys. Mapping was classified into ice-marginal (e.g. moraine ridges, trimlines), subglacial (e.g. glacial lineations, flutes), glaciolacustrine (e.g. palaeolake shorelines, perched deltas), glaciofluvial (e.g. proglacial outwash plains, meltwater channels), and non-glacial (e.g. palaeochannels, landslides or slumps) landform groups. The new map will inform future interpretations of regional glacier dynamics, and the development of robust geochronological datasets that test the timing of glaciation and deglaciation.