This study presents a 64-year （1951-2014） reconstruction of the surface mass balance of Glacier No. 31, located in the Suntar-Khayata Range of the eastern Siberia, where the ablation zone is characterized by the ext...This study presents a 64-year （1951-2014） reconstruction of the surface mass balance of Glacier No. 31, located in the Suntar-Khayata Range of the eastern Siberia, where the ablation zone is characterized by the extensive dark ice surface. We use a temperature index-based glacier mass-balance model, which computes all major components of glacier mass budget and is forced by daily air temperature and precipitation from a nearby meteorological station. The glacier shows a mean annual mass balance of -0.35 m w.e.a-1 during the past 64 years, with an acceleration of -0.50 m w.e. a^-1 during the recent years. A cumulative mass loss of the glacier is -22.3 m w.e. over the study period, about 56% of which is observed during 1991-2014. In addition to the contribution of temperature rise and precipitation decrease to recent mass loss of the glacier, an experimental analysis, in which the clean and dark ice surfaces are respectively assumed to cover the entire ablation zone, indicates that dark ice surface, caused by insoluble impurities consisting of mineral dusts, eryoconite granules, and ice algae, plays a crucial role in the changing mass balance through enhancing melt rates in the ablation zone of the glacier.展开更多
Biogeochemical feedback processes between soil organic carbon (SOC) in high-latitude organic soils and climate change is of great concern for projecting future climate. More accurate models of the SOC stock and its dy...Biogeochemical feedback processes between soil organic carbon (SOC) in high-latitude organic soils and climate change is of great concern for projecting future climate. More accurate models of the SOC stock and its dynamics in organic soil are of increasing importance. As a first step toward creating a soil model that accurately represents SOC dynamics, we have created the Physical and Biogeochemical Soil Dynamics Model (PB-SDM) that couples a land surface model with a SOC dynamics model to simulate the feedback cycle of SOC accumulation and thermal hydrological dynamics of high-latitude soils. The model successfully simulated soil temperatures for observed data from a boreal forest near Fairbanks, and 2000 year simulations indicated that the effect of the feedback cycle of SOC accumulation on soil thickness would result in a significant differences in the amount of SOC.展开更多
基金supported by the National Basic Work Program of the Ministry of Science and Technology of China(MOST)(Grant No.2013FY111400)the Major Project of Chinese Academy of Sciences(Grant No.KZZD-EW-12-1)MEXT through the Green Network of Excellence(GRENE)Arctic Climate Change Research Project
文摘This study presents a 64-year （1951-2014） reconstruction of the surface mass balance of Glacier No. 31, located in the Suntar-Khayata Range of the eastern Siberia, where the ablation zone is characterized by the extensive dark ice surface. We use a temperature index-based glacier mass-balance model, which computes all major components of glacier mass budget and is forced by daily air temperature and precipitation from a nearby meteorological station. The glacier shows a mean annual mass balance of -0.35 m w.e.a-1 during the past 64 years, with an acceleration of -0.50 m w.e. a^-1 during the recent years. A cumulative mass loss of the glacier is -22.3 m w.e. over the study period, about 56% of which is observed during 1991-2014. In addition to the contribution of temperature rise and precipitation decrease to recent mass loss of the glacier, an experimental analysis, in which the clean and dark ice surfaces are respectively assumed to cover the entire ablation zone, indicates that dark ice surface, caused by insoluble impurities consisting of mineral dusts, eryoconite granules, and ice algae, plays a crucial role in the changing mass balance through enhancing melt rates in the ablation zone of the glacier.
文摘Biogeochemical feedback processes between soil organic carbon (SOC) in high-latitude organic soils and climate change is of great concern for projecting future climate. More accurate models of the SOC stock and its dynamics in organic soil are of increasing importance. As a first step toward creating a soil model that accurately represents SOC dynamics, we have created the Physical and Biogeochemical Soil Dynamics Model (PB-SDM) that couples a land surface model with a SOC dynamics model to simulate the feedback cycle of SOC accumulation and thermal hydrological dynamics of high-latitude soils. The model successfully simulated soil temperatures for observed data from a boreal forest near Fairbanks, and 2000 year simulations indicated that the effect of the feedback cycle of SOC accumulation on soil thickness would result in a significant differences in the amount of SOC.
