Paleoclimate modelling is one of the core topics in the Past Global Changes project under the International Geosphere-Biosphere Programme and has received much attention worldwide in recent decades. Here we summarize ...Paleoclimate modelling is one of the core topics in the Past Global Changes project under the International Geosphere-Biosphere Programme and has received much attention worldwide in recent decades. Here we summarize the research on the Paleoclimate modeling, including the Holocene, Last Glacial Maximum, and pre-Quaternary climate intervals or events performed at the Institute of Atmospheric Physics under the Chinese Academy of Sciences （IAP/CAS） for over one decade. As an attempt to review these academic activities, we emphasize that vegetation and ocean feedbacks can amplify East Asian climate response to the Earth＇s orbital parameters and atmospheric CO2 concentration at the mid-Holocene. At the Last Glacial Maximum, additional cooling in interior China is caused by the feedback effects of East Asian vegetation and the ice sheet over the Tibetan Plateau, and the regional climate model RegCM2 generally reduces data-model discrepancies in East Asia. The simulated mid-Pliocene climate is characterized by warmer and drier conditions as well as significantly weakened summer and winter monsoon systems in interior China. On a tectonic timescale, both the Tibetan Plateau uplift and the Paratethys Sea retreat play important roles in the formation of East Asian monsoon-dominant environmental pattern during the Cenozoic.展开更多
The temperature anomaly and dust concentrations recorded from central Antarctic ice core records display a strong negative correlation. The dust concentration recorded from an ice core in central Antarctica is 50-70 t...The temperature anomaly and dust concentrations recorded from central Antarctic ice core records display a strong negative correlation. The dust concentration recorded from an ice core in central Antarctica is 50-70 times higher during glacial periods than interglacial periods. This study investigated the impact of dust aerosol on glacial-interglacial climate, using a zonal energy balance model and dust concentration data from an Antarctica ice core. Two important effects of dust, the direct radiative effect and dust-albedo feedback, were considered. On the one hand, the direct radiative effect of dust significantly cooled the climate during the glacial period, with cooling during the last glacial maximum being as much as 2.05℃ in Antarctica. On the other hand, dust deposition onto the ice decreased the surface albedo over Antarctica, leading to increased absorption of solar radiation, inducing a positive feedback that warmed the region by as much as about 0.9℃ during the glacial period. However, cooling by the direct dust effect was found to be the controlling effect for the glacial climate and may be the major influence on the strong negative correlation between temperature and dust concentration during glacial periods.展开更多
Glacial outburst floods（GLOFs） in alpine regions tend to be relatively complicated, multi-stage catastrophes, capable of causing significant geomorphologic changes in channel surroundings and posing severe threats t...Glacial outburst floods（GLOFs） in alpine regions tend to be relatively complicated, multi-stage catastrophes, capable of causing significant geomorphologic changes in channel surroundings and posing severe threats to infrastructure and the safety and livelihoods of human communities. GLOF disasters have been observed and potential hazards can be foreseen due to the newly formed glacial lakes or the expansion of existing ones in the Poiqu River Basin in Tibet, China. Here we presented a synthesis of GLOF-related studies including triggering mechanism（s）, dam breach modeling, and flood routing simulation that have been employed to reconstruct or forecast GLOF hydrographs. We provided a framework for probability-based GLOFs simulation and hazard mapping in the Poiqu River Basin according to available knowledge. We also discussed the uncertainties and challenges in the model chains, which may form the basis for further research.展开更多
对位于北疆福海县的乌伦古湖Ulungur10B孔岩芯进行分析,以AMS^(14)C测年为年代框架,结合粒度、烧失量和色度指标重建了该地区12.3 cal ka BP以来的古环境演化。结果显示:12.3~11.2 cal ka BP期间,湖泊有机质含量较高,区域有效湿度较大;1...对位于北疆福海县的乌伦古湖Ulungur10B孔岩芯进行分析,以AMS^(14)C测年为年代框架,结合粒度、烧失量和色度指标重建了该地区12.3 cal ka BP以来的古环境演化。结果显示:12.3~11.2 cal ka BP期间,湖泊有机质含量较高,区域有效湿度较大;11.2~7.4 cal ka BP期间,沉积物平均粒径大,有机质含量低,色度a*值、b*值偏大,区域气候冷干,湖面水位较低;7.4~4.3 cal kaBP期间,沉积物平均粒径减小,有机质含量升高,色度a*值、b*值减小,区域气候暖湿,湖泊水位较高;4.3 cal ka BP以来指标在波动中变化,反映湖泊水位在波动中变化,区域有效湿度有所降低。乌伦古湖晚冰期以来古环境演化与周边环境记录一致,气候变化模式符合中亚干旱区全新世气候变化的西风模式。展开更多
基金the National Natural Science Foundation of China under Grant Nos. 40620130113 , 40405015 by tile CAS Innovative Research International Partnership Project.
文摘Paleoclimate modelling is one of the core topics in the Past Global Changes project under the International Geosphere-Biosphere Programme and has received much attention worldwide in recent decades. Here we summarize the research on the Paleoclimate modeling, including the Holocene, Last Glacial Maximum, and pre-Quaternary climate intervals or events performed at the Institute of Atmospheric Physics under the Chinese Academy of Sciences （IAP/CAS） for over one decade. As an attempt to review these academic activities, we emphasize that vegetation and ocean feedbacks can amplify East Asian climate response to the Earth＇s orbital parameters and atmospheric CO2 concentration at the mid-Holocene. At the Last Glacial Maximum, additional cooling in interior China is caused by the feedback effects of East Asian vegetation and the ice sheet over the Tibetan Plateau, and the regional climate model RegCM2 generally reduces data-model discrepancies in East Asia. The simulated mid-Pliocene climate is characterized by warmer and drier conditions as well as significantly weakened summer and winter monsoon systems in interior China. On a tectonic timescale, both the Tibetan Plateau uplift and the Paratethys Sea retreat play important roles in the formation of East Asian monsoon-dominant environmental pattern during the Cenozoic.
基金jointly supported by the National Basic Research Program of China(Grant No.2012CB955301)the Fundamental Research Funds for the Central Universities(Grant No.lzujbky-2012-124)the Program for Changjiang Scholars and Innovative Research Team in University(PCSIRT)
文摘The temperature anomaly and dust concentrations recorded from central Antarctic ice core records display a strong negative correlation. The dust concentration recorded from an ice core in central Antarctica is 50-70 times higher during glacial periods than interglacial periods. This study investigated the impact of dust aerosol on glacial-interglacial climate, using a zonal energy balance model and dust concentration data from an Antarctica ice core. Two important effects of dust, the direct radiative effect and dust-albedo feedback, were considered. On the one hand, the direct radiative effect of dust significantly cooled the climate during the glacial period, with cooling during the last glacial maximum being as much as 2.05℃ in Antarctica. On the other hand, dust deposition onto the ice decreased the surface albedo over Antarctica, leading to increased absorption of solar radiation, inducing a positive feedback that warmed the region by as much as about 0.9℃ during the glacial period. However, cooling by the direct dust effect was found to be the controlling effect for the glacial climate and may be the major influence on the strong negative correlation between temperature and dust concentration during glacial periods.
基金funded by the National Key Technology Research and Development Programthe Key Basic Research Program of the Ministry of Science and Technology of China (2012BAC19B07, 2013FY111400)the National Natural Science Foundation of China (41190084)
文摘Glacial outburst floods（GLOFs） in alpine regions tend to be relatively complicated, multi-stage catastrophes, capable of causing significant geomorphologic changes in channel surroundings and posing severe threats to infrastructure and the safety and livelihoods of human communities. GLOF disasters have been observed and potential hazards can be foreseen due to the newly formed glacial lakes or the expansion of existing ones in the Poiqu River Basin in Tibet, China. Here we presented a synthesis of GLOF-related studies including triggering mechanism（s）, dam breach modeling, and flood routing simulation that have been employed to reconstruct or forecast GLOF hydrographs. We provided a framework for probability-based GLOFs simulation and hazard mapping in the Poiqu River Basin according to available knowledge. We also discussed the uncertainties and challenges in the model chains, which may form the basis for further research.
文摘对位于北疆福海县的乌伦古湖Ulungur10B孔岩芯进行分析,以AMS^(14)C测年为年代框架,结合粒度、烧失量和色度指标重建了该地区12.3 cal ka BP以来的古环境演化。结果显示:12.3~11.2 cal ka BP期间,湖泊有机质含量较高,区域有效湿度较大;11.2~7.4 cal ka BP期间,沉积物平均粒径大,有机质含量低,色度a*值、b*值偏大,区域气候冷干,湖面水位较低;7.4~4.3 cal kaBP期间,沉积物平均粒径减小,有机质含量升高,色度a*值、b*值减小,区域气候暖湿,湖泊水位较高;4.3 cal ka BP以来指标在波动中变化,反映湖泊水位在波动中变化,区域有效湿度有所降低。乌伦古湖晚冰期以来古环境演化与周边环境记录一致,气候变化模式符合中亚干旱区全新世气候变化的西风模式。
