Geoscience Letters最新文献_第3页

Geochemical characteristics and origin of the formation water of the Saline Lake Basin: a case study of the Quaternary Qigequan Formation in the Sanhu Depression, Qaidam Basin 盐湖盆地地层水的地球化学特征及成因：柴达木盆地三湖凹陷第四纪垣曲地层个案研究

IF 4 3区地球科学

Geoscience Letters Pub Date : 2024-03-19 DOI: 10.1186/s40562-024-00332-y

Xiaoxue Liu, Zhenxue Jiang, Xianglu Tang, Jun Zhu, Fenying Zhang, Yuchao Wang, Mingshuai Xu

{"title":"Geochemical characteristics and origin of the formation water of the Saline Lake Basin: a case study of the Quaternary Qigequan Formation in the Sanhu Depression, Qaidam Basin","authors":"Xiaoxue Liu, Zhenxue Jiang, Xianglu Tang, Jun Zhu, Fenying Zhang, Yuchao Wang, Mingshuai Xu","doi":"10.1186/s40562-024-00332-y","DOIUrl":"https://doi.org/10.1186/s40562-024-00332-y","url":null,"abstract":"Clarifying the geochemical characteristics of formation water and its origin is conducive to clarifying the gas migration path, elaborating the law of gas migration and accumulation, and further predicting the favourable area of gas accumulation. Taking Quaternary formation water from the Tainan-Sebei area of the Sanhu Depression as the research object, the chemical characteristics and origin of the region are clarified using anion analysis, cation analysis, hydrogen isotope analysis, oxygen isotope analysis and so on. The results are as follows. (1) The formation water in the study area has a high total dissolved solids (TDS) content and is mainly type IV and V of CaCl2. (2) Low r(Na+)/r(Cl−), low desulfurization coefficient, high r(Ca2+)/r(Mg2+) and high indices of base exchange indicate that the Qigequan Formation is in a stagnant zone, which is beneficial for the accumulation and preservation of biogenic gas. (3) Due to albitization and water–rock reactions, the formation water is rich in Ca2+, poor in Na+ and poor in Mg2+. (4) The formation water in the study area originates from the glacial meltwater of the Kunlun Mountains, which converts into groundwater and seeps into the formation along the piedmont slope zone. In the process of groundwater infiltration and convergence, many salt substances in the formation are dissolved, resulting in a gradual increase in TDS. Then, the formation water with a high TDS migrates to the anticline in the northern part of the depression and is finally trapped in the formation.","PeriodicalId":48596,"journal":{"name":"Geoscience Letters","volume":"55 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140166029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Extreme precipitation trends in Northeast China based on a non-stationary generalized extreme value model 基于非平稳广义极值模型的中国东北地区极端降水趋势

IF 4 3区地球科学

Geoscience Letters Pub Date : 2024-03-15 DOI: 10.1186/s40562-024-00331-z

Fangxiu Meng, Kang Xie, Peng Liu, Huazhou Chen, Yao Wang, Haiyun Shi

{"title":"Extreme precipitation trends in Northeast China based on a non-stationary generalized extreme value model","authors":"Fangxiu Meng, Kang Xie, Peng Liu, Huazhou Chen, Yao Wang, Haiyun Shi","doi":"10.1186/s40562-024-00331-z","DOIUrl":"https://doi.org/10.1186/s40562-024-00331-z","url":null,"abstract":"Northeast China is the main food production base of China. Extreme precipitation (EP) events can seriously impact agricultural production and socioeconomics, but the understanding of EP in Northeast China is still limited. In this study, using the non-stationary generalized extreme value (GEV) model, we investigate the trend and potential risk of EP in Northeast China during 1959–2017, especially in early and mid-summer (periods of high frequency of EP). Then, the relationships between EP and large-scale circulation over Northeast China in early and mid-summer are analyzed separately. The EP in Northeast China mainly presents positive trends in early summer but negative trends in mid-summer. Meanwhile, the EP with all the return periods presents apparently increasing trends in early summer, corresponding to more frequent EP events. Nevertheless, in mid-summer, the EP with 2-year return period decreases with location parameter, and the EP with 20-year, 50-year, and 100-year return periods slightly increases with scale parameter. The EP with 2-year return period occurs frequently in Liaoning Province, while the EP with 100-year return period is more likely to occur in Jilin Province and Heilongjiang Province. Moreover, the increase of the EP in early summer is mainly influenced by the northeast cold vortex; the effect of cold air on the EP is stronger in mid-summer, giving a clear explanation why the EP in mid-summer does not increase significantly. Overall, the outcomes of this study would be beneficial for the disaster prevention and mitigation in Northeast China.","PeriodicalId":48596,"journal":{"name":"Geoscience Letters","volume":"48 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140153249","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spatial comparison of inland water observations from CYGNSS, MODIS, Landsat, and commercial satellite imagery 来自 CYGNSS、MODIS、Landsat 和商业卫星图像的内陆水观测数据的空间比较

IF 4 3区地球科学

Geoscience Letters Pub Date : 2024-03-07 DOI: 10.1186/s40562-024-00321-1

G. K. Pavur, H. Kim, B. Fang, V. Lakshmi

{"title":"Spatial comparison of inland water observations from CYGNSS, MODIS, Landsat, and commercial satellite imagery","authors":"G. K. Pavur, H. Kim, B. Fang, V. Lakshmi","doi":"10.1186/s40562-024-00321-1","DOIUrl":"https://doi.org/10.1186/s40562-024-00321-1","url":null,"abstract":"Accurate and timely inland waterbody extent and location data are foundational information to support a variety of hydrological applications and water resources management. Recently, the Cyclone Global Navigation Satellite System (CYGNSS) has emerged as a promising tool for delineating inland water due to distinct surface reflectivity characteristics over dry versus wet land which are observable by CYGNSS’s eight microsatellites with passive bistatic radars that acquire reflected L-band signals from the Global Positioning System (GPS) (i.e., signals of opportunity). This study conducts a baseline 1-km comparison of water masks for the contiguous United States between latitudes of 24°N-37°N for 2019 using three Earth observation systems: CYGNSS (i.e., our baseline water mask data), the Moderate Resolution Imaging Spectroradiometer (MODIS) (i.e., land water mask data), and the Landsat Global Surface Water product (i.e., Pekel data). Spatial performance of the 1-km comparison water mask was assessed using confusion matrix statistics and optical high-resolution commercial satellite imagery. When a mosaic of binary thresholds for 8 sub-basins for CYGNSS data were employed, confusion matrix statistics were improved such as up to a 34% increase in F1-score. Further, a performance metric of ratio of inland water to catchment area showed that inland water area estimates from CYGNSS, MODIS, and Landsat were within 2.3% of each other regardless of the sub-basin observed. Overall, this study provides valuable insight into the spatial similarities and discrepancies of inland water masks derived from optical (visible) versus radar (Global Navigation Satellite System Reflectometry, GNSS-R) based satellite Earth observations.","PeriodicalId":48596,"journal":{"name":"Geoscience Letters","volume":"299 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140055123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluating precipitation prediction skill for the pre- and postrainy seasons in South China in ECMWF subseasonal forecasts 评估 ECMWF 副季节预报对华南雨季前后降水的预测能力

IF 4 3区地球科学

Geoscience Letters Pub Date : 2024-03-05 DOI: 10.1186/s40562-024-00325-x

Yanan Liu, Qiong Wu, Yizhi Zhang, Lujun Jiang

{"title":"Evaluating precipitation prediction skill for the pre- and postrainy seasons in South China in ECMWF subseasonal forecasts","authors":"Yanan Liu, Qiong Wu, Yizhi Zhang, Lujun Jiang","doi":"10.1186/s40562-024-00325-x","DOIUrl":"https://doi.org/10.1186/s40562-024-00325-x","url":null,"abstract":"The rainy season in South China is divided into two phases, the pre- and postrainy seasons, according to the seasonal progression of the East Asian summer monsoon. The precipitation prediction skills for the two rainy seasons are investigated using subseasonal-to-seasonal (S2S) hindcast data from the European Centre for Medium-Range Weather Forecasts (ECMWF) for 2001–2019. The precipitation prediction skills and biases differ between the two rainy seasons, although some similar characteristics exist regarding circulation patterns and their influence on precipitation. During the two rainy seasons, the prediction ability of circulation at 850 hPa in key areas is relatively high, and the influence of circulation on precipitation is well captured; additionally, the relationship between circulation in key areas at 500 hPa and precipitation is less accurately constrained. Moreover, the precipitation prediction skill in the prerainy season is higher than that in the postrainy season. The main bias is that the 200 hPa westerly winds provide favorable divergence conditions for prerainy season precipitation (preprecipitation), while the postrainy season precipitation (postprecipitation) displays almost no correlation with the circulation in the reanalysis product; however, the simulated circulation at 200 hPa is closely connected to the precipitation in both rainy seasons; therefore, the lower prediction skill in the postrainy season is likely associated with overestimation of the complex physical mechanism of the upper-level circulation in the model.","PeriodicalId":48596,"journal":{"name":"Geoscience Letters","volume":"27 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140036379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Simulating 2-D magnetotelluric responses using vector-quantized temporal associative memory artificial neural network-based approaches 利用基于矢量量化时间关联记忆人工神经网络的方法模拟二维磁突触响应

IF 4 3区地球科学

Geoscience Letters Pub Date : 2024-03-02 DOI: 10.1186/s40562-024-00328-8

Phongphan Mukwachi, Banchar Arnonkijpanich, Weerachai Sarakorn

引用次数: 0

Rethinking our world: a perspective on a cleaner globe emerging from reduced anthropogenic activities 反思我们的世界：从减少人为活动的角度看更清洁的地球

IF 4 3区地球科学

Geoscience Letters Pub Date : 2024-02-27 DOI: 10.1186/s40562-024-00322-0

Kim-Anh Nguyen, Yuei-An Liou

{"title":"Rethinking our world: a perspective on a cleaner globe emerging from reduced anthropogenic activities","authors":"Kim-Anh Nguyen, Yuei-An Liou","doi":"10.1186/s40562-024-00322-0","DOIUrl":"https://doi.org/10.1186/s40562-024-00322-0","url":null,"abstract":"Stringent measures, such as lockdowns, were implemented to curb the virus's spread, leading to reduced pollution levels and environmental improvements at various geographic scales, from cities to regions and nations. Such positive effects have been found and reported for regional scales, but not for a global scale till nowadays. This study aims to fill the gap by uncovering the modifications of global spatiotemporal eco-environmental vulnerability patterns between pre-pandemic (2016) and amid-pandemic (2020) periods. By analyzing various factors influencing the eco-environmental health or geo-health, such as human activities, climate change, and ecological dynamics, we seek to understand the intricate relationships and dynamics within these influential factors. We examined six categories of environmental vulnerability, which encompassed socioeconomics, land resources, natural hazards, hydrometeorology, and topography, using a five-dimensional stressor framework. Our analysis revealed a significant decrease in vulnerability levels across all categories, except for the very low level increased by 78.5% globally. These findings emphasize the detrimental impact of human activities on the global environment. They underscore the urgency of implementing spatial management strategies that prioritize sustainable geo-health development and foster a more resilient Earth.","PeriodicalId":48596,"journal":{"name":"Geoscience Letters","volume":"17 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140001787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Multi-year assessment of the impact of ship-borne radiosonde observations on polar WRF forecasts in the Arctic 船载无线电探测仪观测对北极极地 WRF 预报影响的多年评估

IF 4 3区地球科学

Geoscience Letters Pub Date : 2024-02-26 DOI: 10.1186/s40562-024-00326-w

Yonghan Choi, Joo-Hong Kim, Sang-Yoon Jun, Taejin Choi, Xiangdong Zhang

{"title":"Multi-year assessment of the impact of ship-borne radiosonde observations on polar WRF forecasts in the Arctic","authors":"Yonghan Choi, Joo-Hong Kim, Sang-Yoon Jun, Taejin Choi, Xiangdong Zhang","doi":"10.1186/s40562-024-00326-w","DOIUrl":"https://doi.org/10.1186/s40562-024-00326-w","url":null,"abstract":"To compensate for the lack of conventional observations over the Arctic Ocean, ship-borne radiosonde observations have been regularly carried out during summer Arctic expeditions and the observed data have been broadcast via the global telecommunication system since 2017. With these data obtained over the data-sparse Arctic Ocean, observing system experiments were carried out using a polar-optimized version of the Weather Research and Forecasting (WRF) model and the WRF Data Assimilation (WRFDA) system to investigate their effects on analyses and forecasts over the Arctic. The results of verification against reanalysis data reveal: (1) DA effects on analyses and forecasts; (2) the reason for the year-to-year variability of DA effects; and (3) the possible role of upper-level potential vorticity in delayed DA effects. The overall assimilation effects of the extra data on the analyses and forecasts over the Arctic are positive. Initially, the DA effects are the most apparent in the temperature variables in the middle/lower troposphere, which spread to the wind variables in the upper troposphere. The effects decrease with time but reappear after approximately 120 h, even in the 240-h forecasts. The effects on forecasts vary depending on the proximity of the radiosonde observation locations to the high synoptic variability. The upper-level potential vorticity is known to play an important role in the development of Arctic cyclones, and it is suggested as a possible explanation for the delayed DA effects after about 120 h.","PeriodicalId":48596,"journal":{"name":"Geoscience Letters","volume":"86 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139969334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

China: legacy collieries versus renewable energy 中国：遗留煤矿与可再生能源

IF 4 3区地球科学

Geoscience Letters Pub Date : 2024-02-25 DOI: 10.1186/s40562-024-00327-9

Zhaoxiang Chu, Yiming Wang, Yukun Ji, Xiaozhao Li

引用次数: 0

Enhanced impacts of the North Pacific Victoria mode on the Indian summer monsoon onset in recent decades 近几十年来北太平洋维多利亚模式对印度夏季季风开始的影响增强

IF 4 3区地球科学

Geoscience Letters Pub Date : 2024-02-25 DOI: 10.1186/s40562-024-00324-y

Suqin Zhang, Xia Qu, Gang Huang

{"title":"Enhanced impacts of the North Pacific Victoria mode on the Indian summer monsoon onset in recent decades","authors":"Suqin Zhang, Xia Qu, Gang Huang","doi":"10.1186/s40562-024-00324-y","DOIUrl":"https://doi.org/10.1186/s40562-024-00324-y","url":null,"abstract":"Victoria mode (VM), the second dominant mode of North Pacific sea surface temperature variability, has been identified as one of the important factors influencing the Indian summer monsoon (ISM) onset. The positive phase of the May VM delays the ISM onset by both tropical and extratropical pathways. Here, we found a significant interdecadal enhancement of their relationship since the early 1990s, which is mainly attributed to the structure changes and increased variance of the VM. In recent decades, the VM has shown more significant warm SST anomalies in the tropical central Pacific, which drive the large-scale divergent circulation more effectively. This enhanced divergent circulation leads to low-level divergence and reduced rainfall in the tropical Asian summer monsoon region. The reduced rainfall excites equatorial Rossby wave response and anomalous easterly winds in the northern Indian Ocean, delaying the ISM onset. Besides, the increased variance of the VM after 1992/1993 stimulates a stronger extratropical Rossby wave train. This stationary Rossby wave train induces a stronger cooling to the northwest of India, which weakens the land-sea thermal contrast and leads to the delayed ISM onset. This finding should be taken into account to improve short-term predictions of the monsoon onset.","PeriodicalId":48596,"journal":{"name":"Geoscience Letters","volume":"244 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139945763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Application of a weighted ensemble forecasting method based on online learning in subseasonal forecast in the South China 基于在线学习的加权集合预报方法在华南副季节预报中的应用

IF 4 3区地球科学

Geoscience Letters Pub Date : 2024-01-30 DOI: 10.1186/s40562-024-00319-9

Fei Xin, Yichen Shen, Chuhan Lu

{"title":"Application of a weighted ensemble forecasting method based on online learning in subseasonal forecast in the South China","authors":"Fei Xin, Yichen Shen, Chuhan Lu","doi":"10.1186/s40562-024-00319-9","DOIUrl":"https://doi.org/10.1186/s40562-024-00319-9","url":null,"abstract":"Under the proposal of “seamless forecasting”, it has become a key problem for meteorologists to improve the skills of subseasonal forecasts. Since the launch of the subseasonal-to-seasonal (S2S) plan by WMO, the precision of model predictions has been further developed. However, when we are focusing on the practical applications of models in the South China (SC) in recent years, we found that large disagreements appear between forecast members. Some of the members predicted well in this area, while others are not satisfactory. To improve the accuracy of subseasonal forecast in the SC, new methods making full use of different forecast models must be proposed. In this passage, we introduced a weighted ensemble forecasting method based on online learning (OL) to overcome this difficulty. As the state-of-the-art forecast models in the world, three models from China Meteorological Administration, European Centre for Medium-Range Weather Forecasts and National Centers for Environmental Prediction provided by the S2S prediction dataset are used as ensemble members, and an ensemble weight is trained through the aforementioned OL model for the predictions of temperature and precipitation in subseasonal timescale in the SC. The results show that the forecast results produced under the OL method are better than the original model predictions. Compared with the three model ensemble results, the weighted ensemble model has a good ability in depicting the temperature and precipitation in the SC. Furthermore, we also compared this strategy against the climatology predictions and found out that the weighted ensemble model is superior in 10–30 days. Thus, the weighted ensemble method trained thorough OL may shed light on improving the skill of subseasonal forecasts.","PeriodicalId":48596,"journal":{"name":"Geoscience Letters","volume":"81 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139586048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0