This study analyzed pollen in snow pits dug in September 2008 and September 2009 upstream of Potanin Glacier in the Mongolian Altai Mountains, which is a summer accumulation-type glacier, to investigate the environment for recent snow deposits. The snow pit observations in both years were carried out at sites 0 and 4, which are 3752 and 3890 m above sea level, respectively. Seasonal layers of the pits were identified according to the taxon of pollen scattered during different seasons. In the 2007 and 2008 layers, concentration peaks of pollen taxa scattered from spring to summer were found at the same depth. Thus, the summer melt reached the spring layer such that pollen grains in the melted layer became concentrated on the summer melt surface and caused the pollen peaks. In contrast, the concentration peaks associated with each season appeared at different depths in the 2009 layer, suggesting that the degree of melting in 2009 was less than that in 2007 and 2008. This interpretation was supported by summer temperature data (June-August) for this region. Deviations in summer air temperatures from mean monthly temperatures for the summers of

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To investigate the characteristics of ablation at Koryto Glacier, a mountain glacier under maritime climate in Kamchatka Peninsula, Russia, we made field observations from August to early September 2000. At a site near the equilibrium line, the 31‐day average net radiation, sensible heat flux, and latent heat flux were 43, 59 and 31 W−2, respectively. We developed a new distributed ablation model, which only needs measurements of air temperature and global radiation at one site. Hourly ablation rates at this site obtained by the energy balance method are related to measured air temperature and global radiation by linear multiple regression. A different set of multiple regression coefficients is fitted for snow and ice surfaces. Better estimates of ablation rate can be obtained by this approach than by other temperature index models. These equations are then applied to each grid cell of a digital elevation model to estimate spatially distributed hourly melt. Air temperature is extrapolated using a constant temperature lapse rate and global radiation is distributed considering topographic effects. The model enables us to calculate the hourly spatial distribution of ablation rates within the glacier area and could well provide a realistic simulation of ablation over the whole glacier.

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