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China is the country with the most population in the world, and its climate is extremely diverse due to tremendous differences in latitude, longitude, and altitude, ranging from tropical in the far south to subarctic in the far north and alpine in the higher elevations of the Qinghai-Tibetan Plateau. Accurate assessment of its modern climate change is conductive to addressing global warming threat. Along with the development of Past Global Changes (PAGES) research, the focus has changed from paleo-climate reconstructions to using paleo-data for assessing the present and predicting the future. Previous studies have been devoted to climate change assessment using modern climate observations and simulations. This paper presents a new assessment approach based on the mid-Holocene, which provides a naturally oriented warming that can be compared to modern human-made global warming. A variety of climatic data, including modern observations, paleo-climate records, CMIP5 (Coupled Model Intercomparison Project Phase 5) and PMIP3 (Paleoclimate Modelling Intercomparison Project 3) simulations, as well as lake level models, were applied in this synthesis. Numerical climate classification was introduced to evaluate climate change impacts to Chinese climate zones on various time scales. The results show that winter and summer seasons have different response to the naturally oriented mid-Holocene warming but human-made global warming makes the warming trend appear in all seasons. Temperate and continental dry winter climates expand dramatically during the mid-Holocene warm period; however, the future global warming could have few impacts to Chinese climate zones. Furthermore, the East Asian summer monsoon was strengthened obviously by the mid-Holocene warm climate and strong low-latitude insolation. There is no consistent trend both for the winter and summer monsoon on the background of human-made global warming. In this study, a new benchmark was established based on paleo-climate to evaluate the impacts of human-made global warming. [ABSTRACT FROM AUTHOR]

Abstract: Interglacials of the Quaternary Period are currently the focus of a great deal of attention within the scientific community. This is primarily because they play a vital role in distinguishing between “natural” and “human” climate change in the current interglacial and in understanding how the Holocene would evolve in the absence of anthropogenic greenhouse warming. In this respect, Marine Isotope Stage 11 (MIS 11, ca 410,000yr BP) is one of the key interglacial stages of the past 450,000yr. The pattern of insolation variability that occurs during MIS 11 matches that which occurs in the Holocene more closely than in any other warm stage of the past half a million years. In addition there is now an extensive range of evidence for MIS 11 palaeoclimates and palaeoenvironments from marine, ice core, lacustrine and terrestrial sequences. The aim of this paper is to provide a comprehensive review of the current state of our understanding of MIS 11. This is the first paper to provide a detailed review of MIS 11 that incorporates the wide range of marine, ice core, long lacustrine and terrestrial records that have been generated over the last ten years since the last major overview. Crucially, it is the first review of MIS 11 that incorporates a detailed synthesis of the high-resolution terrestrial sequences of western and central Europe. This paper, therefore, provides a holistic integration of a diverse range of proxies and archives to provide a detailed understanding of the expression of MIS 11 in the Earth system. In particular the review focuses on: (1) the climatic background of MIS 11, (2) the robustness of the identification of MIS 11 in a diverse range of sequences, (3) the climatic structure of MIS 11, (4) the magnitude of warmth that occurred in this warm stage, (5) MIS 11 sea level magnitude and variability, (6) the duration of MIS 11, (7) evidence for abrupt climatic events within the interglacial of MIS 11 and (8) precipitation patterns and trends during this interglacial. The paper concludes by considering how useful MIS 11 is as an analogue for Holocene climates and compares it with other proposed analogues, such as MIS 19, with particular reference to the “early anthropogenic” hypothesis. [Copyright &y& Elsevier]

Abstract: Sediment deposition in floodplains is an essential part of the sediment dynamics of a catchment. These sediment dynamics can vary largely on a Holocene time scale under the influence of driving forces such as land use and climatic variations. In this paper we review the Holocene floodplain sediment deposition history of rivers in West and Central Europe, with special attention to the influence of climate and land use variability. During the early Holocene (Preboreal to Atlantic Period), most floodplains were rather stable with limited floodplain aggradation. After this initial phase of relative stability, sedimentation rates increase during the Middle and Late Holocene, with often the most important deposition phase during the last 1000 to 2000 a. The start of the increase in sedimentation varies spatially, with an earlier start in the west (France, Germany) then in the east (Poland, Belarus, Ukraine), while there are also local differences between regions which are settled early (e.g. loess regions) compared to later settled regions. The sedimentation history of most floodplains can be linked to the local land use history, while influence of climatic variations on floodplain aggradation is often reported to be of minor importance. Processes related to bedload are often reported to be more influenced by climatic events. Relationships between the driving forces and the sediment history are mainly based on synchronicity, and there is seldom proof for a direct causal relationship. Future research should focus on a system-based approach, integrating the floodplain deposition in the entire sediment dynamics which includes also erosion, colluvial deposition and export. Main research questions that need further attention include integration of system-based concepts, like landscape connectivity and buffering effects, and also the assessment of the individual contribution of land use changes and climatologic variations on the sediment dynamics. Detailed sediment budget studies combined with modeling studies can make an important contribution to the understanding of floodplain sediment dynamics. [Copyright &y& Elsevier]