Inconsistent reconstructions of East Asian hydroclimate for the last millennium significantly limit our understanding of the mechanisms behind climate variability during the medieval climate anomaly (MCA) and little ice age (LIA) in the region. In this study, we present new high-resolution multiproxy records (diatom, δ13C, C/N, TS) from the Mulyoungari swamp, Jeju Island, South Korea. Our results indicate that El Niño southern oscillation-like variations caused the dry MCA/wet LIA pattern in the study area. Recent paleo-ENSO studies generally support the hypothesis that the MCA was characterized by more persistent El Niño-like conditions. During El Niño events, the genesis of typhoons affecting coastal East Asia tends to diminish because of warm anomalies of eastern tropical Pacific (ETP) SSTs and downward motions over the western tropical Pacific. Therefore, coastal East Asia likely experienced a decline in typhoon-related precipitation during the MCA, in contrast to monsoon-dominated northern China. Our results additionally imply that SST anomalies in the ETP need to be carefully checked to better understand current hydroclimate variability in coastal East Asia, one of the most populated areas on earth.

In this study, we present a high-resolution multi-proxy record (pollen, magnetic susceptibility, and mean grain size) from Bigeum Island, South Korea, which mainly showed early Holocene paleoenvironmental change. Bigeum pollen records indicated that early Holocene climate variations in coastal East Asia were principally controlled by the Atlantic meridional overturning circulation. Most importantly, the 8.2 ka cooling event was clearly recognized for the first time in coastal East Asia, where few high-resolution proxy data, such as ice core and stalagmite δ18O records, are available. The insular vegetation in the study site was extremely susceptible to even short-term climate changes, such as the 8.2 ka cooling event, which allowed a detailed climate reconstruction from pollen data. Early Holocene climate teleconnections between coastal East Asia and other regions were identified through regional comparisons of Greenland, China, Brazil, Spain, Madagascar, and Korea. Coastal East Asia is one of world’s most populated regions and will be particularly vulnerable to future climate change. Accurate and detailed paleoclimate proxy data, such as the Bigeum pollen record, will therefore be increasingly important in this region.

The dynamics of the East Asian Summer Monsoon (EASM) and their link to past societies during the Holocene are topics of growing interest. In this study, we present results of pollen, geochemistry, and grain-size analyses from the STP18-03 core sampled from Miryang in the Korean Peninsula, which spans ca. 8.3–2.3 ka BP. In-phase relationships of these proxies revealed an imprint of the Holocene Climate Optimum (HCO) during the early to mid-Holocene and subsequent drying toward the late-Holocene in accordance with decreasing solar insolation. At centennial timescales, our study indicates drier climate during ca. 7.5–7.1, 6.4–6.0, and 4.8–3.6 ka BP. Notably, our finding for ca. 6.4–6.0 ka BP contributes further evidence of a drying event in the Korean Peninsula during this period. We suggest that the Pacific Ocean played a role in the underlying mechanism of hydroclimate change in the region. A strong Kuroshio Current (KC) and long-term El Niño–Southern Oscillation (ENSO)-like variability in the Western Tropical Pacific (WTP) were closely linked to the influence of the EASM over the Korean Peninsula. In particular, dry phases during ca. 4.8–3.6 and 2.8–2.3 ka BP, which were synchronous with a more active ENSO, closely corresponded to lower population levels indicated by a summed probability distribution (SPD) of archaeological records previously assembled in the Korean Peninsula. This finding implies that past human societies of Korea were highly vulnerable to climate deterioration caused by precipitation deficits.

Since december 2019, an increasing number of cases associated with the 2019 novel coronavirus (2019-ncoV) have emerged in Wuhan, china, which has resulted in a rapid outbreak in china and worldwide. The present study aimed to describe the clinical, laboratory and radiological characteristics of 2019-ncoV pneumonia (ncP) in Zhejiang province, outside of Wuhan. a total of 74 patients with 2019-ncoV were continuously enrolled between January 22 and March 2, 2020 at Zhejiang Hospital. Diagnosis was confirmed at Zhejiang Hospital by reverse transcription-Pcr (rT-Pcr), which was approved by the chinese government. Subsequently, the clinical features between positive-and negative-ncP patients in Zhejiang were compared. among the 74 hospitalized patients with suspected 2019-ncP, six patients (one male and five female patients) were confirmed to be infected with 2019-nCoV by RT-PCR. The average age of the confirmed patients was 40±13 years. There were three family clusters among the confirmed cases, one patient from each of these families had travel history or contact with patients from Wuhan within 2 weeks. compared with non-ncP patients, the most common symptoms at onset for patients with ncP were fever (5/6; 83.3%) and cough (5/6; 83.3%), followed by dyspnea/pharyngalgia (2/6; 33.3%), whereas myalgia (1/6; 16.7%) and fatigue (1/6; 16.7%) were less common. all 74 patients with suspected ncP exhibited abnormal computerized tomography (cT) images. in total, 2/6 (33.3%) patients with confirmed NCP presented with bilateral pneumonia, and 21/68 (30.9%) non-ncP patients exhibited bilateral pneumonia, with bilateral distribution of patchy shadows or ground glass opacity. The present study revealed that epidemiological history was critical to the diagnosis of 2019-ncoV in low epidemic regions outside Hubei province. it was also identified that chest CT could not replace nucleic acid testing due to similar radiological manifestations.

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