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Abstract The recent colder winters in midlatitude Eurasia have been proposed to result from Arctic sea-ice decline. However, large uncertainties remain regarding this link in the present variable climate. Here, we present ice-rafted debris records from the eastern Arctic and geochemical data from the temperate East China Sea to reconstruct Holocene changes in sea ice and the East Asian winter monsoon. Our reconstructions and climate numerical simulations revealed enhanced Arctic sea-ice decline but warmer winters in East Asia in the mid-Holocene than in the late Holocene. In the warmer mid-Holocene, enhanced Arctic sea-ice loss transferred more heat from intensive summer solar insolation to the winter atmosphere, suppressing meridional heat transport; thus, less high-latitude cold air moved to lower latitudes in Asia due to the weakened winter monsoon. Our findings imply that the colder winters in East Asia may not change the long-term trend toward winter warming in the context of Arctic sea-ice decline.

Abstract The climate response of tropical Southeast Asia to abrupt climate change originating from high northern latitudes remains poorly understood. Here, marine sediments recovered from the Northwest Borneo Trough are analyzed to trace variations in terrigenous material composition associated with sea level and palaeoflood activities over the past 40 ka. We describe for the first time the influence of sea level change on terrigenous deposition from a tropical island with small mountainous rivers surrounded by narrow continental shelves and the coupling between North Atlantic dynamics and climate feedbacks in tropical Southeast Asia during the Dansgaard‐Oeschger stadials. This study demonstrates that climate oscillations occurring at high northern latitudes can be transmitted to tropical Southeast Asia through the functions of sea level, the East Asian winter monsoon and the Intertropical Convergence Zone. Such information is fundamental to correctly assessing future sea level rise and flood risks in tropical Southeast Asia.

The latitude-dependent periodicity of East Asian hydroclimate during the Quaternary was probably a response to summer insolation in the north and ice sheet forcing in the south, suggested by analyses of proxy-based rainfall records and climate model simulations.

Abstract Despite the importance of the westerlies to the global climate system, we still know little about their long‐term evolution and possible orographic controls during the late Cenozoic because of the lack of sedimentary records with precise chronological control. Eolian deposition in the North Pacific preserved past information about the westerlies, the major wind system delivering Asian dust to the Pacific. A continuous, high‐resolution eolian flux record since 23 Ma was reconstructed from sediments at Deep Sea Drilling Project Site 296 in the North Pacific. Combined with dust flux at Ocean Drilling Program Site 1208, variations in their difference indicated a northwards shift of the westerlies during 23‒9 Ma and a relatively stable state since then. We suggest that Tibetan uplift since the early Miocene began to drive the poleward shift of the westerlies until 9 Ma, after which the westerlies remained relatively stable over Asia on million‐year timescales.

The distribution and evolution of C4 plants are closely related to climate change. However, with the development of agriculture, to what extent human activities affect the natural environment and play an important role in controlling C3/C4 vegetation remains unclear. In this study, the carbon isotopic composition of black carbon (BC) extracted from sediments in core CSDP-1 in the western South Yellow Sea was used to reconstruct the evolution of C3/C4 vegetation in the Yellow River Basin since ∼7 ka BP. The results show that the warm and humid climate in northern China was more suitable for C4 plant growth during the middle Holocene. The relative abundance of C4 plants in the source region, the Yellow River Basin, decreased with lower temperature and precipitation from 7 to 3 ka BP. However, after ∼3 ka BP, the inherent relationship between climate and vegetation growth decoupled, with rapid expansion of C4 plants under cooling and drying climates. We suggest that strengthened human activity (including deforestation and cultivating C4 crops) replaced climate as the main factor affecting C3/C4 vegetation during the late Holocene.

Abstract Ischemic insult stimulates proliferation of neural stem cells (NSCs) in the subventricular zone (SVZ) after stroke. However, only a fraction of NSC‐derived neuroblasts from SVZ migrate toward poststroke brain region. We have previously reported that direct‐current stimulation guides NSC migration toward the cathode in vitro. Accordingly, we set up a new method of transcranial direct‐current stimulation (tDCS), in which the cathodal electrode is placed on the ischemic hemisphere and anodal electrode on the contralateral hemisphere of rats subjected to ischemia–reperfusion injury. We show that the application of this bilateral tDCS (BtDCS) promotes the migration of NSC‐derived neuroblasts from SVZ toward the cathode direction into poststroke striatum. Reversing the position of the electrodes blocks the effect of BtDCS on the migration of neuroblasts from SVZ. BtDCS protects against neuronal death and improves the functional recovery of stroke animals. Thus, the migration of NSC‐derived neuroblasts from SVZ toward poststroke brain region contributes to the effect of BtDCS against ischemia‐induced neuronal death, supporting a potential development of noninvasive BtDCS as an endogenous neurogenesis‐based stroke therapy.