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This paper provides another look at the response of the Asian summer monsoon (ASM) to insolation forcing and oceanic feedback during the Holocene, using a fully coupled general circulation ocean–atmosphere model forced by Earth’s orbital variations. The model results revealed a recurrent circumglobal teleconnection (CGT) pattern in the summertime (June–July–August) mid-latitude circulation of the Northern Hemisphere during the Holocene. The CGT index showed a decreasing trend before ~5 ka BP and a slight increasing trend afterwards, affected by the combined effects of summer insolation, Indian summer monsoon (ISM), North Atlantic and Indian Ocean–western Pacific Ocean sea surface temperature (SST). The CGT showed a close relationship with ASM precipitation and surface air temperature during the Holocene and, therefore, could act as a bridge linking the ASM to insolation, high-latitude forcing (North Atlantic SST), and low-latitude forcing (tropical Ocean SST). We emphasize that the mid-latitude atmospheric circulation has been a key factor for the evolution of the ASM during the Holocene. In addition, the CGT provides a viable explanation for the out-of-phase relationship in the moisture evolution but an in-phase relationship in the speleothem δ18O between arid central Asia and the ISM region during the Holocene. [ABSTRACT FROM AUTHOR]

Identifying and explaining changes in the prehistoric material and social world is one of the greatest research interests in archaeology, palaeoclimate and environmental science. In the last two decades or so, a considerable number of studies have made significant contributions to the associated disciplines in eastern Asian archaeology. However, due to the more specialised scientific approaches and the rapid accumulation of new excavation materials, it becomes increasingly difficult for scholars to examine and correlate research outputs from different areas and achieve a holistic picture of the past. Using eastern Asian archaeology as an example, this Special Issue aims to break down the disciplinary boundaries and present the current research debate on how to correlate different climate, environmental and social changes and explain human past. One of the fundamental issues is the lack of adequate chronological resolution to order various archaeological events. To tackle this, a large number of radiocarbon dates, primarily derived from short- lived materials, are provided in the Special Issue. A great variety of changes in local environment, agricultural practice, animal husbandry, technologies, migration, demography and social organisations are revealed in the following papers but there are two profound drivers to all of these changes. One is the broad climate change since the start of the Holocene and the other is the communication between the West and the East. [ABSTRACT FROM AUTHOR]

A comprehensive and integrative view of East Asian monsoon evolution during the Holocene is still under debate, and additional high-resolution proxy records from climatically sensitive locations are requisite to solve this complex issue. In this paper, we present three well-dated mud/peat cores from a paleo-pingo depression in the Sanjiang Plain, a climatically sensitive region to monsoon variation, to reveal the paleoenvironmental history of the wetland and discuss the regional impacts from monsoon evolution. A paleolake developed in the study area before 5.5 ka BP, and a peatland initiated thereafter consequent upon the gradual shrinking of the paleolake. This transition lasted until 4.5 ka BP, when the paleolake changed entirely to a wetland. Considering the prevalent monsoon climate in the Sanjiang Plain, we suggest that the lake-to-wetland transition from 5.5 to 4.5 ka BP indicates a rapid decline of the East Asian summer monsoon in addition to autogenic basin infilling processes. Such a remarkable monsoon weakening event has been documented across northern China, and we associate this with ocean–atmosphere interactions throughout low-latitude regions. [ABSTRACT FROM AUTHOR]

In a recent special issue of The Holocene, Miller et al. review the evidence for the spread of millet (Panicum miliaceum and Setaria italica) across Eurasia. Among their arguments, they contend that millet cultivation came to Eurasian regions with hot, dry summers when irrigation was introduced, as part of a region-wide shift toward agricultural intensification in the first millennium BC. This hypothesis seems to align with the pattern of agricultural change observed in the Khorezm oasis, a Central Asian polity of the first millennium BC and first millennium AD. While we wholeheartedly accept this hypothesis for its explanatory value regarding trends across Eurasia, in this paper we nevertheless suggest that the introduction of millet to Central Asia needs further explication. Specifically, we seek to address the underlying assumption that this introduction was predicated upon centrally organized, state-level land development, increased sedentism, and the rise of Mesopotamian-style social complexity. We describe how millet cultivation in Khorezm was preceded by multi-resource strategies that included the cultivation of summer crops, and emphasize that this earlier history mattered significantly to the evolution of Khorezmian society and agriculture in the first millennium BC. In contrast to the imperial systems of West Asia, in Khorezm the introduction of complex irrigation works supported the expansion and greater stratification of pre-existing agropastoral lifeways, and helped to buttress the rise of nomadic elites within an agrarian zone. We believe the example of Khorezm is important because it helps to explain the emergence of integrated mobilesedentist societies in the first millennium AD in Central Asia as a result of agricultural change. It also provides cultural and historical context to the spread of millet cultivation in the first millennium BC, suggesting that this phenomenon had significantly different implications for societies across Eurasia. [ABSTRACT FROM AUTHOR]

For well over a century, scholars from across the social and biological sciences have been trying to understand the origins and spread of agriculture. This debate is often intertwined with discussions of climate change and human environmental impact. Over the past decade, this debate has spread into Central Eurasia, from western China to Ukraine and southern Russia to Turkmenistan, a part of the world often thought to have been largely dominated by pastoralists. A growing interest in the prehistory of Central Eurasia has spurred a new chapter in the origins of agriculture debate; archaeobotanical research is showing how important farming practices in this region were in regard to the spread of crops across the Old World. While early people living in Central Eurasia played an influential role in shaping human history, there is still limited understanding of the trajectories of social evolution among these populations. In March 2015, 30 leading scholars from around the globe came together in Berlin, Germany, to discuss the introduction and intensification of agriculture in Central Eurasia and adjacent regions. At the German Archaeological Institute in Berlin (Deutsches Archäologisches Institut, DAI), these scholars presented novel data on topics covering East, South, and Central Asia, spanning a wide realm of methodological approaches. The present special edition volume deals with a selection of the papers given at this conference, and it marks a significant step toward recognizing the contribution of Central Eurasian populations in the spread and development of agricultural systems over the course of the Holocene. [ABSTRACT FROM AUTHOR]

The moisture history in arid central Asia (ACA) differs from that in the Asian monsoon region during the Holocene. Much less is known about causes of Holocene moisture changes in ACA than Asian monsoon precipitation changes, hampering our understanding of their spatiotemporal differences. In this study, orbital-scale evolution of winter rainfall in northwestern China (a part of the core zone in ACA) during the Holocene and possible driving mechanisms are investigated using results from a long-term transient simulation performed by an atmosphere–ocean–sea-ice coupled general circulation model, the Kiel Climate Model, forced by orbital variations. Our results reveal a persistent wetting trend in northwestern China in winter throughout the Holocene, which is in response to winter insolation at mid-northern latitudes. Winter insolation can influence the rainfall via three ways. First, increasing latitudinal gradient of the incoming solar insolation at mid-latitudes strengthens the westerly intensity. Second, the evaporation is enhanced because of insolation-induced winter temperature rising, resulting in an increase in the air humidity. Intensified westerly winds and the increased water vapour together are conductive to enhance moisture transport towards northwestern China and thus increase winter precipitation in this area. Third, the increasing trend of winter insolation weakens the East Asian winter monsoon, which is favourable for the formation of rainfall via crippling the Siberian High that is beneficial for atmospheric lifting motion. [ABSTRACT FROM AUTHOR]