Spatial Distribution of the Input of Insoluble Particles Into the Surface of the Qaanaaq Glacier, Northwestern Greenland

From glaciological observations, we found spatial variation in the input of insoluble particles (ISP) on a glacier surface from atmospheric deposition and outcropping at the surface of the glacier by surface ablation at the ablation area of the Qaanaaq Ice Cap in northwestern Greenland. Possible sources of ISP input to the glacier surface were outcropping at the surface of the glacier by ablation at intermediate and low elevations, and from atmospheric deposition at high elevations. The annual atmospheric deposition of ISP was larger at high elevations than at intermediate and low elevations. The annual abundance of outcropping ISP was larger at intermediate elevations than at low elevations, where the annual ablation rate of the glacier surface was 1.5 times larger than at intermediate elevations. The ISP concentration in the glacier ice at intermediate sites was approximately 10 times larger than at low sites. The water stable isotopes of glacier ice at intermediate sites indicated that glacier ice at the intermediate sites did not form since the last glacial maximum, possibly the Holocene Thermal Maximum. Therefore, the accumulation of the ISP, which is outcropping at the intermediate site, occurred at high elevations after Holocene Thermal Maximum.