Timing and configuration of the Gongga II glaciation in the Hailuogou valley, eastern Tibetan Plateau: A glacier-climate modeling method

The timing and extent of late Quaternary glaciation in the Hailuogou valley of eastern Tibetan Plateau have been extensively studied over past decades. Debate however exists in the timing of the Gongga II moraine that represents the maximum glaciation in the Hailuogou valley. Furthermore, the Gongga II glaciation is not quantitatively reconstructed; and what climate conditions could support this maximum glaciation is unknown. This study used a glacier-climate model driven by data from local weather stations to simulate the Gongga II glacier extent by fitting modeled glaciers to field geological evidence. Running multiple simulations with different temperature-precipitation combinations, we inferred the climate scenarios sufficient to generate the Gongga II glacier extent. The modeled Gongga II glaciers have an area of ∼119 km2 and an average volume of 1.35 × 1010 m3, with an average equilibrium-line altitude of 4050 m asl. Combined with other independent climate reconstructions, the glacier-climate model simulations suggested that the Gongga II glacial stage most likely occurred in the LGM.