作者机构：
[Mao, Dehua; Wang, Ting; Deng, Meirong] Hunan Normal Univ, Sch Geog Sci, Changsha 410081, Peoples R China.;[Deng, Meirong; Hu, Zui] Hengyang Normal Univ, Coll Geog & Tourism, Hengyang 421002, Peoples R China.;[Mao, Dehua; Wang, Ting; Deng, Meirong] Hunan Prov Key Lab Ecoenvironm Changes & Carbon Se, Changsha 410081, Peoples R China.;[Li, Yeye] Xinjiang Univ, Coll Ecol & Environm, Urumqi 830046, Peoples R China.
通讯机构：
[Mao, DH ] H;Hunan Normal Univ, Sch Geog Sci, Changsha 410081, Peoples R China.;Hunan Prov Key Lab Ecoenvironm Changes & Carbon Se, Changsha 410081, Peoples R China.
关键词：
water-related ecosystem services;InVEST model;ecological management zoning;trade-off and synergy;Xiangjiang River Basin
摘要：
Exploring the spatiotemporal distribution and interrelationships among water-related ecosystem services (WESs) and conducting ecological management zoning are crucial for regional sustainable development. Taking the Xiangjiang River Basin (XJRB) as an example, this study first quantified three primary WESs, including water conservation, soil retention, and water purification, from 2000 to 2020. Second, the spatiotemporal variation in the interrelationships among WESs were analyzed using global and local bivariate spatial autocorrelation. Third, a water ecological zoning rule was constructed to divide the watershed into three primary and eight secondary water ecological management zones. The results indicate a strong consistency in the changes in the three WESs throughout the period from 2000 to 2020 in the XJRB. Precipitation patterns and urban expansion were the primary factors affecting alterations in the WESs. Spatial heterogeneity and dependence were evident across these ecosystem services. Both trade-offs and synergies were observed among WESs, with synergies playing a dominant role. Positive synergies occurred primarily in woodlands and grasslands, while negative synergies were observed in cultivated land, water areas, and construction land. Three water ecological management zones, including core water ecological management zones, general management zones, and restoration management zones, were delineated at the grid and country scales according to the aggregation properties of the WESs. Ecological management strategies were proposed for different zones. These findings can offer valuable insights for policy makers in land use planning and water ecological management within the XJRB, and can facilitate similar management endeavors in other regions.
摘要：
The urban mobility structure is a summary of individual movement patterns and the interaction between persons and the urban environment, which is extremely important for urban management and public transportation route planning. The majority of current research on urban mobility structure discovery utilizes the urban environment as a static network to detect the relationship between people groups and urban areas, ignoring the vital problem of how individuals affect urban mobility structure dynamically. In this paper, we propose a spatio-temporal representational learning method based on reinforcement learning for discovering urban mobility structures, in which the model can effectively consider the interaction knowledge graph of individuals with stations while accounting for the spatio-temporal heterogeneity of individual travel. The experimental results demonstrate the advantages of individual travel-based urban mobility structure discovery research in describing the interaction between individuals and urban areas, which can account for the intrinsic influence more thoroughly.
作者机构：
[Gao, Chanchan] Hengyang Normal Univ, Coll Geog & Tourism, Hengyang 421000, Peoples R China.;[Gao, Chanchan; Liu, Min] East China Normal Univ, Sch Ecol & Environm Sci, Shanghai Key Lab Urban Ecol Proc & Ecorestorat, Shanghai 200241, Peoples R China.;[Liu, Min] Minist Nat Resources, Technol Innovat Ctr Land Spatial Ecorestorat Metro, Shanghai 200241, Peoples R China.
通讯机构：
[Min Liu] T;Technology Innovation Center for Land Spatial Eco-Restoration in Metropolitan Area, Ministry of Natural Resources, Shanghai 200241, China<&wdkj&>Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China<&wdkj&>Author to whom correspondence should be addressed.
摘要：
Particulate matter (PM) pollution has caused several environmental problems and damaged human health. To understand the different driving forces of PM2.5 and PM10, we investigated the spatial distribution of PM2.5, PM10, and the ratio of PM2.5 to PM10 (PM2.5/PM10), and simulated how they respond to socioeconomic, natural conditions and pollutant transmission in 336 cities across Chinese mainland in 2017. The results indicated that 35.4% and 49.7% of cities in Chinese mainland satisfied the national level II standard for PM2.5 (35 mu g/m(3)) and PM10 (70 mu g/m(3)), respectively. The average PM2.5/PM10 was 57.5 +/- 9.4%, which is a relatively high value across the world. Global spatial regression results revealed that the transport of pollutants emitted from neighboring regions was the most important factor for local PM concentrations, while population density was the dominant local variable. The influence of socioeconomic factors and the neighboring pollution level on PM2.5 was greater than that on PM10, while the effect of precipitation was greater on PM10. Cluster analysis revealed that 336 Chinese cities could be classified into three groups. The regions with a high PM concentration and a high level of social economy were included in Group 1 (G1). Group 2 (G2) was predominantly observed in southern China, while Group 3 (G3) was seen in western China. Furthermore, population density significantly affected the PM in G2 and PM2.5 in G3, and PM levels in G1 and G3 had a sensitive response to the variation in precipitation, especially PM10.
关键词：
East Asian winter monsoon (EAWM);Palynology;Mid-Holocene transition;Teleconnection mechanism;Northeast China
摘要：
The East Asian winter monsoon (EAWM) system is one of the most active components of the global winter atmospheric circulation, and it has a major impact on the Eurasian climate in winter. However, relatively few proxy indicators are available to reconstruct the past evolution of the EAWM. Based on the physiology and modern distribution of the temperate forest and boreal forest in Northeast Asia, we found that the northern boundary of temperate pine forest is sensitive to winter temperature and thus it can be used as a proxy for EAWM intensity. A Holocene pollen record from Lake Woniupaozi in Northeast China shows that an expansion of temperate pine forest since ∼6.0 ka cal BP was linked to a weakening of the EAWM. This pattern is consistent with other paleoclimatic records from Northeast Asia and elsewhere, including the North Atlantic region, Middle East, Arabian Sea, and the Tibetan Plateau/Southwest China, which suggests a major climatic transition in the mid-Holocene. The mechanism responsible for this teleconnection may have been the continuous melting of the Laurentide ice which lowered the SST in the North Atlantic and maintained the North Atlantic Oscillation (NAO) in a positive winter phase. This influence was subsequently transmitted from the North Atlantic region to Eurasia via the winter southern Eurasian (SEA) teleconnection.
作者机构：
[Zhang, Zhongbo] Hunan Weather Modificat Off, Changsha 410118, Peoples R China.;[Zhang, Zhongbo] Hunan Key Lab Meteorol Disaster Prevent & Mitigat, Changsha 410118, Peoples R China.;[Liu, Yuan; Tang, Wenwen; Fu, Jing; Fang, Xiaohong; Zhang, Haibo] Hengyang Normal Univ, Coll Geog & Tourism, Hengyang 421002, Peoples R China.;[Fu, Jing] Int Ctr Space Technol Nat & Cultural Heritage HIS, Hengyang Base 421002, Hengyang, Peoples R China.;[Fu, Jing] Hunan Normal Univ, Hunan Key Lab Geospatial Big Data Min & Applicat, Changsha 410081, Peoples R China.
通讯机构：
[Jing Fu] C;College of Geography and Tourism, Hengyang Normal University, Hengyang 421002, China<&wdkj&>International Centre on Space Technologies for Natural and Cultural Heritage (HIST) under the Auspices of UNESCO, Hengyang Base, Hengyang 421002, China<&wdkj&>Hunan Key Laboratory of Geospatial Big Data Mining and Application, Hunan Normal University, Changsha 410081, China<&wdkj&>Author to whom correspondence should be addressed.
摘要：
It is important to reveal the spatial and temporal variations of drought and evaluate the alleviating effects of artificial precipitation on drought severity, as it will contribute immensely to the formulation of drought prevention and mitigation measures and the provision of guidance to artificial precipitation enhancement operation. Based on the monthly precipitation data of 28 meteorological stations in Hengyang-Shaoyang Drought Corridor (HSDC) from 1960 to 2019, the standardized precipitation index (SPI) at multiple time scales were calculated to estimate drought frequency, drought station ratio, and drought intensity. Then the spatiotemporal variations of drought in the study area were unveiled, and the effects of artificial precipitation enhancement were evaluated in line with the relevant data from 2005 to 2019. The results show that at the annual scale, drought occurred in 3/4 of past sixty years in the study area, where almost 1/3 of such years experienced area-wide droughts. Drought coverage in HSDC exhibited a decreasing trend, but drought intensity, as well as the number of area-wide droughts and regional droughts showed an increasing one. Mild and moderate droughts occurred in an extensive part of the HSDC, whereas severe and extreme droughts were mainly found in a few stations. At the seasonal scale, winter drought occurred most frequently, followed by summer and autumn droughts, while spring drought events had the lowest frequency. Overall, drought is more serious in spring, autumn, and winter, but less severe in summer; although drought intensity decreased slightly in summer, both its intensity and coverage showed an increasing trend in other seasons. At the monthly scale, the ratio of positive to negative SPI values in HSDC was basically balanced in the past six decades, exhibiting no distinct variation characteristics. In addition, artificial precipitation enhancement effectively eased monthly and even seasonal drought in HSDC. These findings, which fully reflect the characteristics of drought in the study area, can also raise awareness of the contribution that artificial precipitation could make to drought mitigation, which in turn will contribute to the formulation of appropriate strategies for climate change mitigation and adaptation.
摘要：
Terrestrial evapotranspiration (ET) refers to a key process in the hydrological cycle by which water is transferred from the Earth's surface to lower atmosphere. With spatiotemporal variations, ET plays a crucial role in the global ecosystem and affects vegetation distribution and productivity, climate, and water resources. China features a complex, diverse natural environment, leading to high spatiotemporal heterogeneity in ET and climatic variables. However, past and future ET trends in China remain largely unexplored. Thus, by using MOD16 products and meteorological datasets, this study examined the spatiotemporal variations of ET in China from 2000 to 2019 and analyzed what is behind changes, and explored future ET trends. Climate variation in China from 2000 to 2019 was statistically significant and had a remarkable impact on ET. Average annual ET increased at a rate of 5.3746 mm yr(-1) (P < 0.01) during the study period. The main drivers of the trend are increasing precipitation and wind speed. The increase in ET can also be explained to some extent by increasing temperature, decreasing sunshine duration and relative humidity. The zonation results show that the increase in temperature, wind speed, and precipitation and the decrease in relative humidity had large and positive effects on ET growth, and the decrease in sunshine duration had either promoting or inhibiting effects in different agricultural regions. Pixel-based variations in ET exhibited an overall increasing trend and obvious spatial volatility. The Hurst exponent indicates that the future trend of ET in China is characterized by significant anti-persistence, with widely distributed areas expected to experience a decline in ET. These findings improve the understanding of the role of climate variability in hydrological processes, and the ET variability in question will ultimately affect the climate system.
期刊：
Theoretical and Applied Climatology,2022年150(3):1545-1557 ISSN：0177-798X
通讯作者：
Lian-Tong Zhou
作者机构：
[Liu, Kui] Hengyang Normal Univ, Coll Geog & Tourism, Hengyang 421002, Hunan, Peoples R China.;[Zhou, Lian-Tong; Wang, Zhibiao; Liu, Kui; Chen, Jilong; Liu, Yong] Chinese Acad Sci, Ctr Monsoon Syst Res, Inst Atmospher Phys, POB 2718, Beijing 100190, Peoples R China.
通讯机构：
[Lian-Tong Zhou] C;Center for Monsoon System Research, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
摘要：
In this paper, Japan Meteorological Agency (JRA-55) reanalysis and observational rainfall datasets from the National Climate Center (NCC) of China, as well as satellite datasets from the Tropical Rainfall Measuring Mission (TRMM), Global Precipitation Climatology Project (GPCP), and International Satellite Cloud Climatology Project (ISCCP), are used. The correlation coefficient and fast Fourier transform (FFT) low-pass filter are also used, in order to reveal the interdecadal decrease in autumn rainfall in Southeast China (SEC) after 1990. The close and robust relationship between the interdecadal variation in autumn rainfall in SEC and sea surface temperature (SST) in the tropical Pacific is investigated. The most significant and stable region of correlation is located in 10 degrees S-10 degrees N, 160 degrees E-160 degrees W, in which there also exists interdecadal warming after 1990. Furthermore, the interdecadal warming of SST can induce Gill responses of the atmosphere: a cyclone anomaly is produced on each side of the equator in the lower troposphere, with a westerly anomaly to the west of the dateline, and an anticyclone anomaly is produced in the upper troposphere. In particular, the cyclone anomaly on the northern side of the equator is located in the Northwest Pacific (NWP), and its ambient northerly airflow weakens meridional water vapor transport, as well as the local descending motion and low-troposphere divergence, in favor of the interdecadal decrease in SEC rainfall after 1990. In addition, the sensitive experiments with ECHAM-5.4 model also confirm that the interdecadal warming in the region (10 degrees S-10 degrees N, 160 degrees E-160 degrees W) would motivate the atmospheric Gill response and thereby cause the sinking motion in SEC and support the interdecadal decrease in autumn rainfall in SEC.
作者机构：
[Fan, Xuejiao; Deng, Zhiwei; Liu, Jianxiong; Quan, Bin] Hengyang Normal Univ, Coll Geog & Tourism, Hengyang 421002, Peoples R China.;[Quan, Bin] Hunan Prov Collaborat Innovat Ctr Digital Heritag, Hengyang 421002, Peoples R China.;[Quan, Bin] Hengyang Normal Univ, HIST Hengyang Base, Hengyang 421002, Peoples R China.
通讯机构：
[Bin Quan] C;College of Geography and Tourism, Hengyang Normal University, Hengyang 421002, China<&wdkj&>Hunan Provincial Collaborative Innovation Center for Digital Heritage of Ancient Village and Town Cultural Heritage, Hengyang 421002, China<&wdkj&>HIST Hengyang Base, Hengyang Normal University, Hengyang 421002, China<&wdkj&>Author to whom correspondence should be addressed.
关键词：
land use change;intensity analysis;balance of cultivated land occupation and compensation;Changsha–Zhuzhou–Xiangtan
摘要：
The Changsha-Zhuzhou-Xiangtan region has experienced rapid social and economic development over the past 40 years, and cultivated land has changed dramatically. The contradiction between built and cultivated land has intensified, for which the local government has implemented a series of policies related to cultivated land protection. However, thus far, it is not clear what the substantial effects of the cultivated land protection policies are. To this end, this paper quantitatively characterizes the changes in the Changsha-Zhuzhou-Xiangtan region during the 20 years before and after the implementation of the cultivated land occupation balance policy, based on land use data from 1980, 2000, and 2020 using intensity analysis. In this paper, we examine the types of spatial land use patterns occurring in Changsha-Zhuzhou-Xiangtan since 1980 and explore the transition path of land use types in urban-rural integration. After the cultivated land protection policy, the transformation relationship between land use types and the changing trend of the cultivated land area was analyzed from the landscape scale. The influence of policy factors on the transformation of land use types was revealed. The results show that, from 1980 to 2020, the changing intensity of construction land and unused land was relatively large and was in an active state; the amount of built land in the Changsha-Zhuzhou-Xiangtan region has been growing, with a net increase of 1101 km(2), while the amount of cultivated land has been showing a net decrease, with a net reduction of 677 km(2). Moreover, the cultivated land has mainly been converted into built land, and the lost cultivated land area in Changsha-Zhuzhou-Xiangtan has not been fully compensated elsewhere in the region, indicating that the cultivated land protection policy has not been able to maintain the cultivated land area in Changsha-Zhuzhou-Xiangtan. From 2000 to 2020, cultivated land change was mainly due to exchange, which indicates that the policy has had a particular effect on the protection of cultivated land. Still, if the government wants to achieve the "balance of cultivated land occupation and compensation" goal, it must establish a complete system for the allocation of cultivated land resources. This study can provide a scientific reference for further implementing the cultivated land protection policy, which is thus of great significance for promoting the construction of the Changsha-Zhuzhou-Xiangtan region and its high-quality economic and social development.
作者机构：
[Zhang, Fanyi; Tian, Xin] Southeast Univ, Sch Transportat, Dept Surveying & Mapping Engn, Nanjing 211189, Peoples R China.;[Zhang, Haibo] Hengyang Normal Univ, Coll Geog & Tourism, Hengyang 421002, Peoples R China.;[Jiang, Mi] Sun Yat Sen Univ, Sch Geospatial Engn & Sci, Guangzhou 510275, Peoples R China.
通讯机构：
[Xin Tian] D;Department of Surveying and Mapping Engineering, School of Transportation, Southeast University, Nanjing 211189, China<&wdkj&>Author to whom correspondence should be addressed.
摘要：
Forests are crucial in carbon sequestration and oxygen release. An accurate assessment of forest carbon storage is meaningful for Chinese cities to achieve carbon peak and carbon neutrality. For an accurate estimation of regional-scale forest aboveground carbon density, this study applied a Sentinel-2 multispectral instrument (MSI), Advanced Land Observing Satellite 2 (ALOS-2) L-band, and Sentinel-1 C-band synthetic aperture radar (SAR) to estimate and map the forest carbon density. Considering the forest field-inventory data of eastern China from 2018 as an experimental sample, we explored the potential of the deep-learning algorithms convolutional neural network (CNN) and Keras. The results showed that vegetation indices from Sentinel-2, backscatter and texture characters from ALOS-2, and coherence from Sentinel-1 were principal contributors to the forest carbon-density estimation. Furthermore, the CNN model was found to perform better than traditional models. Results of forest carbon-density estimation validated the improvements effectively by combining the optical and radar data. Compared with traditional regression methods, deep learning has a higher potential for accurately estimating forest carbon density using multisource remote-sensing data.
作者机构：
[Liu, Peilin; Han, Qing; Deng, Yunyuan] Hengyang Normal Univ, Coll Geog & Tourism, Hengyang 421002, Peoples R China.;[Han, Qing; Deng, Yunyuan] Hengyang Normal Univ, Cooperat Innovat Ctr Digitalizat Cultural Heritag, Hengyang 421002, Peoples R China.;[Han, Qing; Deng, Yunyuan] Hengyang Normal Univ, Natl Local Joint Engn Lab Digital Preservat & Inn, Hengyang 421002, Peoples R China.;[Yin, Chao] Guangdong Acad Sci, Guangzhou Inst Geog,Guangdong Open Lab Geospatial, Guangdong Prov Engn Lab Geog Spatiotemporal Big D, Key Lab Guangdong Utilizat Remote Sensing & Geog, Guangzhou 510070, Peoples R China.;[Yin, Chao] Hong Kong Univ Sci & Technol, Dept Civil & Environm Engn, Hong Kong 999077, Peoples R China.
通讯机构：
[Chao Yin] D;Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Hong Kong 999077, China<&wdkj&>Guangdong Province Engineering Laboratory for Geographic Spatio-temporal Big Data, Key Laboratory of Guangdong for Utilization of Remote Sensing and Geographical Information System, Guangdong Open Laboratory of Geospatial Information Technology and Application, Guangzhou Institute of Geography, Guangdong Academy of Sciences, Guangzhou 510070, China<&wdkj&>Author to whom correspondence should be addressed.
摘要：
The classification of architectural style for Chinese traditional settlements (CTSs) has become a crucial task for developing and preserving settlements. Traditionally, the classification of CTSs primarily relies on manual work, which is inefficient and time consuming. Inspired by the tremendous success of deep learning (DL), some recent studies attempted to apply DL networks such as convolution neural networks (CNNs) to achieve automated classification of the architecture styles. However, these studies suffer overfitting problems of the CNNs, leading to inferior classification performance. Moreover, most of the studies apply the CNNs as a black box providing limited interpretability. To address these limitations, a new DL classification framework is proposed in this study to overcome the overfitting problem by transfer learning and learning-based data augmentation technique (i.e., AutoAugment). Furthermore, we also employ class activation map (CAM) visualization technique to help understand how the CNN classifiers work to abstract patterns from the input. Specifically, due to a lack of architectural style datasets for the CTSs, a new annotated dataset is first established with six representative classes. Second, several representative CNNs are leveraged to benchmark the new dataset. Third, to address the overfitting problem of the CNNs, a new DL framework is proposed which combines transfer learning and AutoAugment to improve the classification performance. Extensive experiments are conducted on the new dataset to demonstrate the effectiveness of our framework. The proposed framework achieves much better performance than baselines, greatly mitigating the overfitting problem. Additionally, the CAM visualization technique is harnessed to explain what and how the CNN classifiers implicitly learn for recognizing a specified architectural style.
摘要：
Given environmental or hydrological functions influenced by changing river networks in the development of rapid urbanization, a clear understanding of the relationships between comprehensive urbanization (CUB) and river network characteristics (RNC), storage capacity (RSC), and regulation capacity (RRC) is urgently needed. In the rapidly urbanized Tai Lake Plain (TLP), China, various methods and multisource data were integrated to estimate the dynamics of RNC, RSC, and RRC as well as their interactions with urbanization. The bivariate Moran's I methods were applied to detect and visualize the spatial dependency of RNC, RSC, or RRC on urbanization. Geographically weighted regression (GWR) model was set up to characterize spatial heterogeneity of urbanization influences on RNC, RSC and RRC. Our results indicated that RNC, RSC and RRC variables each showed an overall decreasing trend across space from 1960s to 2010s, particularly in those of tributary rivers. RNC, RSC, or RRC had globally negative correlations with CUB, respectively, but looking at local scale the spatial correlations between each pair were categorized as four types: high-high, high-low, low-low, and low-high. GWR was identified to accurately predict the response of most RNC, RSC, or RRC variables to CUB (R-2: 0.6-0.8). The predictive ability of GWR was spatially non-stationary. The obtained relationships presented different directions and strength in space. All variables except for the water surface ratio (Wp) were more positively affected by CUB in the middle eastern parts of TLP. Drainage density, RSC and RRC variables were more negatively influenced by CUB in the northeast compared to other parts. The quantitative results of spatial relationships between urbanization and RNC, RSC or RRC can provide location-specific guidance for river environment protection and regional flood risk management.
作者机构：
[Liu, Na; Huang, Yimin; Huang, Linjuan; Jiang, Wulin] Hengyang Normal Univ, Coll Geog & Tourism, Hengyang 421002, Peoples R China.;[Jiang, Wulin] Hengyang Normal Univ, Cooperat Innovat Ctr Digitalizat Cultural Heritag, Hengyang 421002, Peoples R China.;[Jiang, Wulin] Int Ctr Space Technol Nat & Cultural Heritage HIS, Hengyang Base 421002, Hengyang, Peoples R China.;[Li, Yilong] Hunan Climate Ctr, Changsha 410118, Peoples R China.;[Xiao, Xiong; Zhang, Cicheng] Hunan Normal Univ, Sch Geog Sci, Changsha 410081, Peoples R China.
通讯机构：
[Na Liu] C;College of Geography and Tourism, Hengyang Normal University, Hengyang 421002, China<&wdkj&>Author to whom correspondence should be addressed.
关键词：
water resources;climatic factors;human activities;Hunan Province
摘要：
The demand for social and economic development has promoted research into water resources. The combined effects of natural conditions and human activities on regional water resource usage are not well understood. The sustainable utilization of water resources was assessed in terms of supply (e.g., precipitation) and demand (e.g., ecological water resources footprint (EFw)) sides in Hunan Province, China, from 2010 to 2019. The results showed that: (1) on the supply side, water resources were increased across Hunan Province. The spatial patterns of total water resources are significantly heterogeneous, with high values in the east and south, which are mainly affected by precipitation; (2) on the demand side, evapotranspiration was great in areas with high vegetation coverage. The EFw was high in relatively developed areas. The mean percentage of agricultural EFw remained dominant at approximately 60% with a steady decreasing trend, while that of eco-environmental EFw increased; and (3) the sustainable utilization of water resources in Hunan Province is generally rational. Moreover, the potential for water resource development and utilization is really significant in eastern and southern Hunan Province. The findings are beneficial in providing an important scientific basis for policymaking relating to the efficient utilization of regional water resources.
作者机构：
[Chen, Fulong; Sun, Zhongchang; Tang, Yunwei; Jing, Linhai; Yang, Wei] Int Res Ctr Big Data Sustainable Dev Goals, Beijing 100094, Peoples R China.;[Chen, Fulong; Sun, Zhongchang; Tang, Yunwei; Jing, Linhai; Yang, Wei] Chinese Acad Sci, Aerosp Informat Res Inst, Key Lab Digital Earth Sci, Beijing 100094, Peoples R China.;[Chen, Fulong] Int Ctr Space Technol Nat & Cultural Heritage Aus, Beijing 100094, Peoples R China.;[Yang, Wei] Univ Chinese Acad Sci, Beijing 100049, Peoples R China.;[Ding, Yanbin] Hengyang Normal Univ, Coll Geog & Tourism, Hengyang 421002, Peoples R China.
通讯机构：
International Research Center of Big Data for Sustainable Development Goals, Beijing, China
关键词：
Cultural landscape;Cultural-heritage site;Interference degree;Object-based image analysis;Very high-resolution
期刊：
Theoretical and Applied Climatology,2022年150(3-4):1173-1186 ISSN：0177-798X
通讯作者：
Lian-Tong Zhou
作者机构：
[Yin, Xiaoxue] China Coast Guard Acad, Dept Nav, Ningbo 315801, Peoples R China.;[Yin, Xiaoxue; Zhou, Lian-Tong; Liu, Kui; Han, Yongqiu; Du, Zhaoyang] Chinese Acad Sci, Inst Atmospher Phys, Ctr Monsoon Syst Res, POB 2718, Beijing 100190, Peoples R China.;[Liu, Kui] Hengyang Normal Univ, Coll Geog & Tourism, Hengyang 421002, Hunan, Peoples R China.;[Du, Zhaoyang] Ningxia Meteorol Observ, Yinchuan 750002, Ningxia, Peoples R China.
通讯机构：
[Lian-Tong Zhou] C;Center for Monsoon System Research, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
摘要：
The Yangtze River valley (YRV) suffered an extreme flood in the early summer (June-July; JJ) 2020, contemporaneous with warm sea surface temperature (SST) over the north Indian Ocean (NIO) and the north tropical Atlantic (NTA) regions. It is suggested that the warm NIO condition played dominant role in the heavy rainfall in China. The present study confirmed the contribution of the NIO warming and examined the underly processes by conducting statistical analysis. There are two ways by which the NIO SSTAs can influence the flooding in JJ 2020 by reinforcing the anomalous western North Pacific anticyclone (WNPAC). One is through an anomalous Kelvin wave in lower level troposphere that propagates into western Pacific and induces suppressed convection. The other is through a reversed Walker circulation over the Indo-Pacific regions that causes divergent circulation in lower level troposphere around WNP. In addition, we show that the warm NTA SSTAs could also enhance WNPAC and YRV flood through an anomalous zonal vertical circulation, with anomalous ascending motion over the NTA region and anomalous descending motion over tropical central-eastern Pacific. The intensified WNPAC facilitated moisture flux transport to YRV through southwesterly anomalies and resulted in extreme flood over YRV in JJ 2020. This study suggests that the NIO and NTA SSTAs can cause extreme flood event in YRV independent of El Niño-Southern Oscillation (ENSO), which highlights the importance of considering SSTAs over the NIO and NTA regions when predicting extreme climate events in China besides ENSO.
作者机构：
[Qin, Rui] Cent South Univ, Sch Geosci & Infophys, Changsha 410083, Peoples R China.;[Chen, Genliang; Qin, Rui] Second Survey & Mapping Inst Hunan Prov, Changsha 410009, Peoples R China.;[Qin, Rui] Cent South Univ, Key Lab Metallogen Predict Nonferrous Met & Geol, Changsha 410083, Peoples R China.;[Chen, Genliang] Minist Nat Resources, Key Lab Nat Resources Monitoring & Supervis South, Changsha 410009, Peoples R China.;[Zhang, Haibo] Hengyang Normal Univ, Coll Geog & Tourism, Hengyang 421002, Peoples R China.
通讯机构：
[Luo Liu] G;Guangdong Province Key Laboratory for Land Use and Consolidation, South China Agricultural University, Guangzhou 510642, China<&wdkj&>Author to whom correspondence should be addressed.
关键词：
land surface temperature;time series;reconstruction;Kalman filter;GMS-5
摘要：
Satellite-derived environmental parameters play important roles in environmental research on global changes and regional resources. Atmosphere effects and sensor limitations often lead to data products that vary in quality. The main goal of time series data reconstruction is to use various statistical and numerical analysis methods and to stimulate changing seasonal or annual parameters, providing more complete data sets for correlational research. This paper aims to develop a time series reconstruction algorithm for LST based on data assimilation according to the current problems of unstable precision and unsatisfactory results, and the simplistic effects of evaluation methods while using remote sensing-derived LST data as the basic parameters and the daily LST data derived from the static meteorological satellite GMS-5 as the input data. The data assimilation system used the Kalman filter as the assimilation algorithm. A complete set of global refined LST time series data sets were obtained by constantly correcting the LST values according to the regional ground-based observations. This method was implemented using MATLAB software (version R2017a), and was applied and validated through partitioning using the principal elevation in the Beijing, Tianjin, and Hebei regions. The results show that the accuracy of the reconstructed LST data series improved significantly in terms of the mean and standard deviation. Better consistency was achieved between the variables obtained over a year from the reconstructed LST data and the ground observations from the LST data set.
期刊：
Open Geosciences,2021年13(1):1552-1560 ISSN：2391-5447
通讯作者：
Ren, Weihe
作者机构：
[Ren, Weihe] Hengyang Normal Univ, Coll Geog & Tourism, Hengyang 421002, Hunan, Peoples R China.;[Li, Quan; Ren, Weihe; Qin, Feng] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China.;[Yi, Guitian] Hengyang Normal Univ, Hengyang 421002, Hunan, Peoples R China.
通讯机构：
[Ren, Weihe] H;[Ren, Weihe] C;Hengyang Normal Univ, Coll Geog & Tourism, Hengyang 421002, Hunan, Peoples R China.;Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China.
关键词：
Asian summer monsoon;2 kyr shift;interglaciations;atmospheric CO2 concentration
摘要：
Holocene records for the Asian Summer Monsoon (ASM) indicate that, apart for the last 2,000 years (“2 kyr shift”), solar insolation was the dominant factor controlling the monsoon climate. The aim of this review is to provide a synopsis of climate characteristics over the last 2 kyr, clarifying mechanisms for the diverse trend with Northern Hemisphere Summer Insolation (NHSI) records. Here, we initially review proxy-based climate reconstructions for the last 2 kyr, and then compare them with records from the last five interglacial periods. Finally, we examine potential physical mechanisms responsible for the “2 kyr shift.” Findings from this review indicate that the “2 kyr shift” is a representative pattern of Holocene climate change within the core area of the ASM, and the “2 kyr shift” could be mainly controlled by changes in atmospheric CO2 concentration. In addition, suggestions to address a more humid condition dominating the Asian monsoonal margin zones are offered.
