Topographic control of asynchronous glacial advances: A case study from Annapurna, Nepal

摘要: [1] Differences in the timing of glacial advances, which are commonly attributed to climatic changes, can be due variations valley topography. Cosmogenic 10Be dates from 24 moraine boulders 5 valleys define two age populations, late-glacial and early Holocene. Moraine ages correlate with paleoglacier hypsometries. Moraines lower maximum altitudes date late-glacial, whereas those higher Two similar equilibrium-line (ELAs), but contrasting ages, <5 km apart share same aspect, such that spatial differences climate excluded. A mass-balance cellular automata model these neighboring predicts change a cooler-drier warmer-wetter (as at Holocene onset) would lead glacier altitude catchment advancing, while one retreats or disappears, even though ELA only shifted by ∼120 m.