Weijian Zhou

Chinese Academy of Sciences | CAS

Despite extensive investigation, the nature and causes of the Mid-Pleistocene Transition remain enigmatic. In this work, we assess its linkage to asynchronous development of bipolar ice sheets by synthesizing Pleistocene mid- to high-latitude proxy records linked to hemispheric ice sheet evolution. Our results indicate substantial growth of the Ant...

Shaanxi Province is located in the most important molybdenum ore district in the world, but a lot of molybdenum tailings have been released, polluting the environment and wasting resources seriously. Taking eleven tailing samples collected at the main molybdenum tailings ponds in Shaanxi Province as the research object, the physical, chemical, and...

Carbon dioxide (CO2) is a major greenhouse gas in the atmosphere and has large impacts on climate change. Its fossil fuel (CO2ff) and biogenic (CO2bio) sources are well investigated, while CO2 emissions from human respiration (CO2hr), a subset of CO2bio, have received less attention. Especially as a source of carbon emissions in densely populated m...

Soil moisture (SM) is essential for sustaining services from Earth’s critical zone, a thin-living skin spanning from the canopy to groundwater. In the Anthropocene epoch, intensive afforestation has remarkably contributed to global greening and certain service improvements, often at the cost of reduced SM. However, attributing the response of SM in...

The long half‐life of ¹²⁹I makes it useful for dating marine sediments aged 2–90 Ma. However, the lack of initial value dating hinders its application for dating terrestrial sediments. A large scatter of ¹²⁹I/¹²⁷I in prenuclear terrestrial samples has been reported; however, the key influencing factors remain unclear. This study presented iodine is...

Despite being exceptionally sensitive to global warming, Holocene temperature records for Central Asia are sparse. Here we report on two high-resolution peatland humification records from Northwestern China. These provide a continuous warm-season temperature record for this region during the Holocene. Warm-season temperatures generally followed sum...

Iodine is a crucial nutrient for public health, and its presence in the terrestrial atmosphere is a key factor in determining the prevalence of iodine deficiency disorders. While oceanic iodine emissions decrease at lower sea surface temperatures, the primary contributors to atmospheric iodine can vary from oceanic sources in the summer to other so...

The Matuyama‐Gauss (M‐G) magnetic polarity reversal is regarded as a fundamental time marker in the stratigraphic division of the Quaternary‐Neogene. However, previous paleomagnetic studies have shown that the M‐G is mainly recorded in the Chinese loess unit L33—a glacial stage (corresponding to marine isotope stage 104, i.e., MIS 104)—which is asy...

Whether there are links between geomagnetic field and Earth's orbital parameters remains unclear. Synchronous reconstructions of parallel long-term quantitative geomagnetic field and climate change records are rare. Here, we present 10Be-derived changes of both geomagnetic field and Asian monsoon (AM) rainfall over the last 870 kyr from the Xifeng...

Reliable chronological frameworks are crucial to paleoenvironmental studies, and high precision 14C dating is the foundation, but many factors, such as dating materials, surficial deposition (influenced by nuclear bomb), and the 14C age plateau, will affect the reliability of the 14C ages and chronology frameworks. In this paper, we present 87 14C...

Sihailongwan Maar Lake, located in Northeast China, is a candidate Global boundary Stratotype Section and Point (GSSP) for demarcation of the Anthropocene. The lake’s varved sediments are formed by alternating allogenic atmospheric inputs and authigenic lake processes and store a record of environmental and human impacts at a continental-global sca...

The Asian summer monsoon (ASM), including the intensity and range limits of it's associated rainfall belt, is relevant to ecosystems, agriculture, natural hazards and water availability for millions of people in this region. However, understanding of the pattern of dunefield changes near the northern limit of the East Asian summer monsoon (EASM) si...

Quantifying fossil fuel CO2 (CO2ff) in the atmosphere provides a benchmark method to monitor anthropogenic carbon emissions. Radiocarbon (¹⁴C) in atmospheric CO2ff has been widely studied using the ¹⁴C in plants to document regional CO2ff patterns. However, annual CO2ff variations, reflecting spatial distributions based on plant samples, are still...

A method using solvent extraction following a preconcentration of iodine by evaporation was developed for separation of iodine in waters associated with coalbed methane (CBM) for the determination of 129I using accelerator mass spectrometry, for exploration of CBM resources. The 129I/127I ratios in water samples collected in a CBM field have been d...

The simulated changes of East Asian monsoonal precipitation between mid-Holocene (MH) and pre-industrial (PI) can be either positive or negative depending on the climate model used. This model disagreement becomes even more severe in the Paleoclimate Model Intercomparison Project Phase 4 with Coupled Model Intercomparison Project Phase 6 (PMIP4-CMI...

Plain Language Summary Numerous sea surface temperature (SST) records indicate long‐term gradual cooling over the Pleistocene, whereas the East Asian summer monsoon (EASM) appears to have strengthened during this period. Land‐sea thermal contrast is thought to have an important influence on the intensity of the EASM, but the lack of land surface te...

Quantifying the timing and extent of Quaternary mountain glaciations can help us in understanding the cause of ice-age cycles. As such, impressive achievements have been made in glacial dynamics across many mountain ranges around the world, such as the Himalayas. Yet, the Marine Isotope Stage 6 (MIS 6) glacial histories have not been well determine...

Plain Language Summary Long‐term monitoring of radionuclides transported with through the atmosphere has significant implications for revealing atmospheric dynamics. The cosmogenic ¹⁰Be/⁷Be is an effective tracer of atmospheric motion. However, the high‐resolution data acquisition is limited because the 7Be‐gamma spectral counting requires large sa...

Changes in land use and land cover (LULC) influence meteorological fields and biogenic emissions, further affecting the atmospheric chemistry and air quality. Combining the satellite measurements and WRF‐Chem model simulations, we evaluate the impacts of the LULC change between 2001 and 2018 on the summertime ozone (O3) formation in North China Pla...

Identifying the sources of atmospheric Carbon dioxide (CO2) is an important prerequisite for developing effective mitigation strategies. Here we conducted regular observations of the atmospheric CO2 mixing ratio and its carbon isotope compositions (i.e., Δ¹⁴C and δ¹³C) in Xi'an and Beijing during winter, to estimate source contributions of CO2 emis...

The El Niño-Southern Oscillation (ENSO) dominates global interannual climate variability and has important socio-economic and environmental consequences. However, determining the history of ENSO variability and its long-term response to climate forcing remains an ongoing challenge owing to the limit of instrumental records. In this study, ENSO vari...

To investigate the characteristics and changes in the sources of carbonaceous aerosols in northern Chinese cities after the implementation of the Action Plan for Air Pollution Prevention and Control in 2013, we collected PM2.5 samples from three representative inland cities, i.e., Beijing (BJ), Xi'an (XA), and Linfen (LF), from January 2018 to Apri...

It is important to know how much of the increased atmospheric CO 2 is derived from fossil fuel emissions. Here, we review the progress in atmospheric fossil fuel CO 2 (CO 2 ff ) tracing over recent years by measurement of Δ ¹⁴ C in Chinese cities. In this paper we make progress by expanding the analysis from some locations to more regional views, b...

This study explores climatic influences contributing to apparently unreliable 14 C ages from loess organic materials. The relationship between anomalous 14 C ages and climate suggests that young/old 14 C age deviations correspond to wet/dry climate periods. Based on stepped-temperature combustion results, we found that the ratio of refractory (old)...

C values of the atmosphere and seawater dissolved inorganic carbon (DIC) were measured during a cruise in the South China Sea (SCS) in September 2015, in order to determine the ¹⁴C flux and bomb ¹⁴C‐based air‐sea CO2 exchange rates for this region. The background atmospheric Δ¹⁴C value (13.8 ± 5.0‰) for the SCS during that period was lower than tha...

The correlation between modern tropical mean annual precipitation (MAP) and its isotopic composition (δp) has been extensively used to interpret terrestrial paleoclimate records. However, the existence of this phenomenon in the past and in individual regions remains a matter of debate. Here, we describe a method for evaluating the relationship betw...

The secondary formation and diffusion processes of aerosol are extraordinarily complex and significantly impact the environment and human health. Therefore, exploring the process of aerosol formation and diffusion based on independent new tracer has always been a concern. The ⁷Be and ¹⁰Be, which are generated only by the action of cosmic rays, are...

In this study, we investigated the characteristics of and changes in the sources of carbonaceous aerosols in northern Chinese cities after the implementation of the Action Plan for Air Pollution Prevention and Control in 2013. We collected PM2.5 samples from three representative inland cities, viz. Beijing (BJ), Xi’an (XA), and Linfen (LF) from Jan...

Across the Miocene–Pliocene boundary (MPB; 5.3 million years ago, Ma), late Miocene cooling gave way to the early-to-middle Pliocene Warm Period. This transition, across which atmospheric CO 2 concentrations increased to levels similar to present, holds potential for deciphering regional climate responses in Asia—currently home to more than half of...

Lacustrine sediments are important archives for paleoclimate research, but there are evident carbon reservoir effects. Radiocarbon ( ¹⁴ C) ages of lake sediments must be corrected for these effects before applying them to paleoclimate research. The authors review the lacustrine research from the last 20 years from different climatic regions in Chin...

Good knowledge on the stable carbon isotopic composition (δ¹³C) of fossil fuels is critical for the estimation of atmospheric CO2 sources. Here, we complied a comprehensive δ¹³C database including 336 coal, 580 oil, and 1160 natural gas data based on the extensive literature search, and conducted field measurements in two megacities, to characteriz...

Quantifying the timing and extent of late Quaternary glaciations across the Tibetan Plateau (TP) is critical to understanding regional and global climate changes. Despite significant advancements in our knowledge of glacial histories of the TP over the past several decades, chronological constraints are still lacking for the high glaciated mountain...

Seasonal climate variability is an important component of Earth's climate system, and has a significant impact on ecosystems and social systems. However, the temporal resolution of most proxy-based paleoclimate records is limiting to fully understand the past seasonal changes. Here, we used high-precision monthly resolution Sr/Ca records of three T...

Lockdown measures to control the spread of the novel coronavirus disease (COVID-19) sharply limited energy consumption and carbon emissions. The lockdown effect on carbon emissions has been studied by many researchers using statistical approaches. However, the lockdown effect on atmospheric carbon dioxide (CO2) on an urban scale remains unclear. He...

Intense Asian summer monsoon rainfall responds to high boreal summer insolation and environmental feedbacks in the early and middle Holocene. However, it is unclear what role of the Asian summer monsoon strength might have played for the heterogeneous wetness pattern in northern China. Here, we report two wet periods in the early and middle Holocen...

Δ¹⁴C values were measured from tree-rings (1948–2018) of Pinus tabuliformis Carr. that grew at the Shangdianzi (SDZ) regional background site in China. The objectives of this study are to establish a record of atmospheric Δ¹⁴C, and to evaluate the influences of Chinese atmospheric nuclear tests and fossil carbon emissions on atmospheric Δ¹⁴C variat...

Radiocarbon (¹⁴C) is a unique and important tool for understanding carbon cycle in the nature, and its use can be significantly enhanced where reliable historical atmospheric Δ¹⁴CO2 records can be established. In China, continuous atmospheric Δ¹⁴CO2 records since the 1950s are scarce, a period when dramatic variations of Δ¹⁴CO2 occurred caused by i...

A wealth of research has demonstrated that polymodal grain size distributions (GSD) in lake sediments can be mathematically decomposed to serve as a more precise tool for paleoenvironmental reconstructions. However, linking grain size subcomponents to specific environmental parameters is sometimes ambiguous, as grain size in lake sediments depends...

Compilation of North American loess, dune, lacustrine, and glacial moraine morphological records at places along the retreating Laurentide Ice Sheet shows intra D-O/Heinrich-scale climate oscillations between 28,000 and 10,000 calibrated years before present (calBP). Grayscale variations of the loess-paleosol record that represents the composite st...

Large variations in pre-nuclear ¹²⁹I/¹²⁷I ratios in terrestrial environments have been observed, but few investigations have been carried out on how the isotopic composition varies and how it is affected by the terrestrial environment. In this work, lake and river sediments were studied for the first time with the aim of exploring the possible conn...

Significance Water vapor emitted from anthropogenic combustion for winter heating in northern China may exacerbate air pollution. This hypothesis is of considerable scientific and environmental interest. We conducted a multiyear sampling campaign of air vapor isotope compositions and associated atmospheric data from the city of Xi’an, located in an...

Paleoclimate change research routinely takes advantage of a variety of climate proxies. Each proxy responds to climate in its own way and a combination of proxies offers the best means of understanding past climate at a given site. Here we present iodine variation patterns in one classical loess-paleosol sequence in the Chinese Loess Plateau to dev...

Interday temperature fluctuations (ITFs) have a series of direct and visible impacts on human productivity, daily life, and some rapidly occurring processes in the Earth's critical zones. The Loess Plateau of China (LPC) is characterized by Chinese continental monsoon climate and fragile ecological environment, and thus, is sensitive to ITFs. To ev...

Cities account for most anthropogenic carbon dioxide (CO2) emissions, and thus play an important role in carbon mitigation. However, the variability of atmospheric CO2 caused by the complex emission sources and topography within city remains a challenge in evaluating urban CO2 emissions. Specifically, the mechanism of spatial and temporal patterns...

Global climate shifted to markedly warmer interglacial conditions across the “mid-Brunhes transition” (MBT, ~400 ka). However, a global MBT synthesis that spans marine and terrestrial evidence remains elusive, which limits our understanding of the role of the MBT in mid-Pleistocene human evolution. We synthesize Asian precipitation reconstructions...

Stephen C. Porter was an international leader in Quaternary science for several decades, having worked on most of the world’s continents and having led international organizations and a prominent interdisciplinary journal. His work influenced many individuals, and he played an essential role in linking Chinese Quaternary science with the broader in...

Massive Gully Land Consolidation projects, launched in China's Loess Plateau, aim to restore 2,667 km2 agricultural lands in total by consolidating 2,026 highly eroded gullies. This effort represents a social engineering project where the economic development and livelihood of the farming families are closely tied to the ability of these emergent l...

A multi-parameter, absolute-dated lacustrine record from the eastern Tibetan Plateau provides a continuous history of the Asian summer monsoon (ASM) over the past ~ 6000 years. The record broadly follows the trend in northern hemisphere summer insolation. However, it diverges during a period of increased moisture and thermal conditions during the p...

The westerly jet (WJ) in the upper troposphere, an important atmospheric circulation system, is critical for influencing global climate by changes of its north–south migration and intensity. However, its variations during the Holocene across the Eurasian and North America are not well evaluated, which restricts our understanding of climate change i...

Significance The Yellow River (YR) is the cradle of Chinese civilization. It supports agriculture, social prosperity, and human survival. YR runoff and sediment load have sharply fallen since the late 1980s. We reconstructed natural runoff history for the middle reach of the YR from 1492 to 2013 CE. We found that the recent low observed YR runoff i...

Magnetic susceptibility (χ) of loess-paleosol sequences on the Chinese Loess Plateau (CLP) has been widely used as a proxy for East Asian summer monsoon (EASM) precipitation variability. Such records typically show strong climate forcing in the ∼100 ka orbital eccentricity band, but exhibit weak precessional (∼23 ka) forcing relative to that seen i...

The marine bivalve, Tridacna spp. is an iconic invertebrate of the Indo-Pacific coral reef communities from Eocene to present. However, field observations found that the population of Tridacna spp. has declined in recent decades and some species are now endangered in the northern South China Sea (SCS) of western Pacific, which are speculated to be...

With the popularization of carbon and nitrogen stable-isotope analysis methods used on archaeological samples from Xinjiang, the ancient paleodiet there has been revealed. However, research about isotopic analysis combined with environmental factors is rare, especially in such a variable and complex climate as that of the Tianshan region. We system...