H. Abdo, Hussein Almohamad, Ahmed Abdullah Al Dughairi, M. Al-Mutiry
Soil erosion is one of the most prominent geomorphological hazards threatening environmental sustainability in the coastal region of western Syria. The current war conditions in Syria has led to a lack of field data and measurements related to assessing soil erosion. Mapping the spatial distribution of potential soil erosion is a basic step in implementing soil preservation procedures mainly in the river catchments. The present paper aims to conduct a comprehensive assessment of soil erosion severity using revised universal soil loss equation (RUSLE) and remote sensing (RS) data in geographic information system (GIS) environment across the whole Al-Qshish river basin. Quantitatively, the annual rate of soil erosion in the study basin was 81.1 t ha−1 year−1 with a spatial average reaching 55.2 t ha−1 year−1. Spatially, the soil erosion risk map was produced with classification into five susceptible-zones: very low (41 %), low (40.5%), moderate (8.9%), high (5.4%) and very high (4.2%). The current study presented a reliable assessment of soil loss rates and classification of erosion-susceptible areas within the study basin. These outputs can be relied upon to create measures for maintaining areas with high and very high soil erosion susceptibility under the current war conditions.
土壤侵蚀是威胁叙利亚西部沿海地区环境可持续性的最突出的地貌灾害之一。叙利亚目前的战争条件导致缺乏与评估土壤侵蚀有关的实地数据和测量。绘制潜在土壤侵蚀的空间分布图是主要在河流集水区实施土壤保护程序的基本步骤。本文旨在利用修正后的通用土壤流失方程（RUSLE）和遥感（RS）数据，在地理信息系统（GIS）环境中对整个Al-Qshish河流域的土壤侵蚀严重程度进行综合评估。从数量上看，研究流域的年土壤侵蚀率为81.1 t ha−1年−1，空间平均值为55.2 t ha−一年−1。从空间上看，土壤侵蚀风险图分为五个易感区：极低（41%）、低（40.5%）、中等（8.9%）、高（5.4%）和极高（4.2%）。目前的研究对研究流域内的土壤流失率和易受侵蚀区域的分类进行了可靠的评估。这些产出可以用来制定措施，在当前战争条件下维护土壤侵蚀敏感性高和非常高的地区。
{"title":"Quantifying the water soil erosion rate using RUSLE, GIS, and RS approach for Al-Qshish River Basin, Lattakia, Syria","authors":"H. Abdo, Hussein Almohamad, Ahmed Abdullah Al Dughairi, M. Al-Mutiry","doi":"10.15233/gfz.2022.39.12","DOIUrl":"https://doi.org/10.15233/gfz.2022.39.12","url":null,"abstract":"Soil erosion is one of the most prominent geomorphological hazards threatening environmental sustainability in the coastal region of western Syria. The current war conditions in Syria has led to a lack of field data and measurements related to assessing soil erosion. Mapping the spatial distribution of potential soil erosion is a basic step in implementing soil preservation procedures mainly in the river catchments. The present paper aims to conduct a comprehensive assessment of soil erosion severity using revised universal soil loss equation (RUSLE) and remote sensing (RS) data in geographic information system (GIS) environment across the whole Al-Qshish river basin. Quantitatively, the annual rate of soil erosion in the study basin was 81.1 t ha−1 year−1 with a spatial average reaching 55.2 t ha−1 year−1. Spatially, the soil erosion risk map was produced with classification into five susceptible-zones: very low (41 %), low (40.5%), moderate (8.9%), high (5.4%) and very high (4.2%). The current study presented a reliable assessment of soil loss rates and classification of erosion-susceptible areas within the study basin. These outputs can be relied upon to create measures for maintaining areas with high and very high soil erosion susceptibility under the current war conditions.","PeriodicalId":50419,"journal":{"name":"Geofizika","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48984576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Marijana Boras, Ivana Herceg-Bulić, Matej Žgela, Irena Nimac
In this study, temperature characteristics and heat load in the city of Dubrovnik are investigated by using temperature data observed at the local meteorological station in Dubrovnik for the period 1961-2019, satellite data collected by LANDSAT5 satellite for the period 2001-2010, and climate indices data obtained from simulations of an urban climate model (MUKLIMO_3) for the period 2001-2010. Trends in daily mean, maximum, minimum, and seasonal temperatures were analysed by using Sen's slope and the Mann-Kendall test. Results reveal rising trends for all of the studied temperature-related elements. However, it is demonstrated that temperature increase is greatest for the summer season with the highest rise for daily maximum temperatures. The same approach was applied to examine trends of climate indices (summer days and tropical nights), which indicates an increase in the number of both summer days and tropical nights. Results of satellite data of average summer land surface temperatures for the period 2001-2010 indicate that urbanised surfaces and bare rock areas heat up more than natural surfaces with vegetation. Climate indices (summer and hot days, warm evenings, and tropical nights) simulated by the urban climate model MUKLIMO_3 also reveal that, on average, in the city of Dubrovnik urbanised surfaces heat up more than natural surfaces with vegetation and that nocturnal heat load is reduced in lower-density built-up areas.
{"title":"Temperature characteristics and heat load in the City of Dubrovnik","authors":"Marijana Boras, Ivana Herceg-Bulić, Matej Žgela, Irena Nimac","doi":"10.15233/gfz.2022.39.16","DOIUrl":"https://doi.org/10.15233/gfz.2022.39.16","url":null,"abstract":"In this study, temperature characteristics and heat load in the city of Dubrovnik are investigated by using temperature data observed at the local meteorological station in Dubrovnik for the period 1961-2019, satellite data collected by LANDSAT5 satellite for the period 2001-2010, and climate indices data obtained from simulations of an urban climate model (MUKLIMO_3) for the period 2001-2010. Trends in daily mean, maximum, minimum, and seasonal temperatures were analysed by using Sen's slope and the Mann-Kendall test. Results reveal rising trends for all of the studied temperature-related elements. However, it is demonstrated that temperature increase is greatest for the summer season with the highest rise for daily maximum temperatures. The same approach was applied to examine trends of climate indices (summer days and tropical nights), which indicates an increase in the number of both summer days and tropical nights. Results of satellite data of average summer land surface temperatures for the period 2001-2010 indicate that urbanised surfaces and bare rock areas heat up more than natural surfaces with vegetation. Climate indices (summer and hot days, warm evenings, and tropical nights) simulated by the urban climate model MUKLIMO_3 also reveal that, on average, in the city of Dubrovnik urbanised surfaces heat up more than natural surfaces with vegetation and that nocturnal heat load is reduced in lower-density built-up areas.","PeriodicalId":50419,"journal":{"name":"Geofizika","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44767982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study used the efficiency of electrical resistivity tomography (ERT) and borehole logs to map the soil-rock interface beneath four traverses (RS1, RS2, RS3, and RS4) in the granitic terrain of Perak, Peninsular Malaysia. The study aimed to evaluate the impacts of the soil-rock characteristic features and interfaces on groundwater and infrastructure development to meet the needs of the increasing inhabitants yearly. The borehole- and ERT-derived lithologic units are strongly correlated. The delineated lithologic units include the topsoil, weathered granitic units (medium stiff to hard silty clay or clayey silt with <800 Ωm), thin to wide-sized weathered/fractured units, and fresh granitic bedrock. These soil-rock profiles and weathered/fractured apertures support sustainable groundwater developments with drill depths above 45 m. In contrast, the delineated clay/silt alternating with stiffer soils, low load-bearing deep-weathered/fractured zones, and bedrock boulders in most places, except beneath traverse RS3, have high affinities for water retention and differential stresses. These features can adversely impact poorly reinforced foundations. Hence, structural elements of the foundations, such as footings or piles, should be placed on stable bedrock, particularly in the central to western parts of the study area. This study has reduced the paucity of information on using ERT and borehole logs for soil-rock interface studies in the study area.
{"title":"Combined ERT and borehole logs for mapping the soil-rock interface in a granitic environment","authors":"Adedibu Sunny Akingboye, A. A. Bery","doi":"10.15233/gfz.2022.39.17","DOIUrl":"https://doi.org/10.15233/gfz.2022.39.17","url":null,"abstract":"This study used the efficiency of electrical resistivity tomography (ERT) and borehole logs to map the soil-rock interface beneath four traverses (RS1, RS2, RS3, and RS4) in the granitic terrain of Perak, Peninsular Malaysia. The study aimed to evaluate the impacts of the soil-rock characteristic features and interfaces on groundwater and infrastructure development to meet the needs of the increasing inhabitants yearly. The borehole- and ERT-derived lithologic units are strongly correlated. The delineated lithologic units include the topsoil, weathered granitic units (medium stiff to hard silty clay or clayey silt with <800 Ωm), thin to wide-sized weathered/fractured units, and fresh granitic bedrock. These soil-rock profiles and weathered/fractured apertures support sustainable groundwater developments with drill depths above 45 m. In contrast, the delineated clay/silt alternating with stiffer soils, low load-bearing deep-weathered/fractured zones, and bedrock boulders in most places, except beneath traverse RS3, have high affinities for water retention and differential stresses. These features can adversely impact poorly reinforced foundations. Hence, structural elements of the foundations, such as footings or piles, should be placed on stable bedrock, particularly in the central to western parts of the study area. This study has reduced the paucity of information on using ERT and borehole logs for soil-rock interface studies in the study area.","PeriodicalId":50419,"journal":{"name":"Geofizika","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44370542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Due to climate change, floods have been more frequent in recent years. Estimating the flood discharge as a result of flood frequency analysis is very substantial to make necessary preparations for possible floods. Data covering 36 years were collected from different stream gauging stations (SGS No: D17A016 and EIEI 1731) in Eastern Mediterranean Basin. With these data, flood discharge values were computed for return periods of 2, 5, 10, 25, 50, 100, 200, 500 and 1000 years. Normal, Log-Normal, Gumbel, Pearson Type III and Log-Pearson Type III statistical distribution methods were used. Kolmogorov-Smirnov (K-S) and Chi-square goodness-of-fit tests were performed to determine which distribution fitted the flood discharge the best. The study showed that the highest flood discharge among the probability distributions for both SGSs came from the Log-Normal distribution, and the lowest discharge was calculated with the Normal distribution. The K-S tests showed that all probability distributions conformed to the 20% significance level. For SGS D17A016, the flood values calculated with Log-Normal distribution were compatible with a 90% confidence interval according to the Chi-square test. Flood values obtained with the other distributions were found within the 10% significance level. In the Chi-square test for SGS EIEI-1731, all probability distributions fell within a 10% significance.
由于气候变化，近年来洪水更加频繁。通过洪水频率分析估算洪水流量，对于为可能发生的洪水做必要的准备是非常重要的。在东地中海盆地的不同河流监测站(SGS编号:D17A016和EIEI 1731)收集了36年的数据。利用这些数据，计算了2、5、10、25、50、100、200、500和1000年汛期的洪水流量值。采用正态、Log-Normal、Gumbel、Pearson Type III和Log-Pearson Type III统计分布方法。采用Kolmogorov-Smirnov (K-S)和卡方拟合优度检验来确定哪个分布最适合洪水流量。研究表明，两大流域的洪水流量在概率分布上均服从对数正态分布，而在概率分布上则服从正态分布。K-S检验表明，所有概率分布符合20%显著性水平。对于SGS D17A016，采用对数正态分布计算的洪水值符合卡方检验的90%置信区间。其他分布得到的洪水值在10%显著性水平内。在SGS EIEI-1731的卡方检验中，所有概率分布的显著性都在10%以内。
{"title":"A comparative study of probability distribution models for flood discharge estimation","authors":"E. Turhan, Serin Değerli","doi":"10.15233/gfz.2022.39.14","DOIUrl":"https://doi.org/10.15233/gfz.2022.39.14","url":null,"abstract":"Due to climate change, floods have been more frequent in recent years. Estimating the flood discharge as a result of flood frequency analysis is very substantial to make necessary preparations for possible floods. Data covering 36 years were collected from different stream gauging stations (SGS No: D17A016 and EIEI 1731) in Eastern Mediterranean Basin. With these data, flood discharge values were computed for return periods of 2, 5, 10, 25, 50, 100, 200, 500 and 1000 years. Normal, Log-Normal, Gumbel, Pearson Type III and Log-Pearson Type III statistical distribution methods were used. Kolmogorov-Smirnov (K-S) and Chi-square goodness-of-fit tests were performed to determine which distribution fitted the flood discharge the best. The study showed that the highest flood discharge among the probability distributions for both SGSs came from the Log-Normal distribution, and the lowest discharge was calculated with the Normal distribution. The K-S tests showed that all probability distributions conformed to the 20% significance level. For SGS D17A016, the flood values calculated with Log-Normal distribution were compatible with a 90% confidence interval according to the Chi-square test. Flood values obtained with the other distributions were found within the 10% significance level. In the Chi-square test for SGS EIEI-1731, all probability distributions fell within a 10% significance.","PeriodicalId":50419,"journal":{"name":"Geofizika","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46212517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Apparent resistivity data from the Offset-Wenner array (Zemun, Serbia), the square array (Bogatić and Golubac, Serbia) and the Wenner tri-potential technique (Vrdnik, Serbia), were used to detect, measure, and reduce lateral effects in 1D inversion. Forward and inverse modelling with the Wenner α, β and γ arrays determined that the Wenner β array provided the most accurate estimate of the first-and second-layer resistivity, while the Wenner γ array provided the most accurate estimate of the high resistivity substratum. The survey on the Zemun loess plateau revealed that if the lateral index of inhomogeneity (LII) is low, the 1D interpretation of both Wenner arrays is justifiable. In addition, the averaging of resistances will result in an apparent resistivity curve that is devoid of lateral effects resulting from near-surface inhomogeneities. As demonstrated by the Vrdnik example, 1D inversion is inadequate when the values of LII and processing covariance (PC) are high. The survey in Golubac was conducted using the square array, which produced lower PC values than collinear arrays. Therefore, the quality of the averaged sounding curve was higher. Also, the interpolated values of the Offset Wenner array displayed reasonable accuracy, while the extrapolated values were inadequate when a low resistivity substratum was present.
{"title":"Improvement of 1D geoelectric sounding by narrowing the equivalence range and identification, quantification and reduction of lateral effects using the tri-potential technique","authors":"F. Arnaut, B. Sretenović, Vesna Cvetkov","doi":"10.15233/gfz.2022.39.15","DOIUrl":"https://doi.org/10.15233/gfz.2022.39.15","url":null,"abstract":"Apparent resistivity data from the Offset-Wenner array (Zemun, Serbia), the square array (Bogatić and Golubac, Serbia) and the Wenner tri-potential technique (Vrdnik, Serbia), were used to detect, measure, and reduce lateral effects in 1D inversion. Forward and inverse modelling with the Wenner α, β and γ arrays determined that the Wenner β array provided the most accurate estimate of the first-and second-layer resistivity, while the Wenner γ array provided the most accurate estimate of the high resistivity substratum. The survey on the Zemun loess plateau revealed that if the lateral index of inhomogeneity (LII) is low, the 1D interpretation of both Wenner arrays is justifiable. In addition, the averaging of resistances will result in an apparent resistivity curve that is devoid of lateral effects resulting from near-surface inhomogeneities. As demonstrated by the Vrdnik example, 1D inversion is inadequate when the values of LII and processing covariance (PC) are high. The survey in Golubac was conducted using the square array, which produced lower PC values than collinear arrays. Therefore, the quality of the averaged sounding curve was higher. Also, the interpolated values of the Offset Wenner array displayed reasonable accuracy, while the extrapolated values were inadequate when a low resistivity substratum was present.","PeriodicalId":50419,"journal":{"name":"Geofizika","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41525000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Laura Bačani, Kristijan Posavec, F. Šumanovac, Josipa Kapuralić
Knowing the soil moisture distribution in the unsaturated zone can improve understanding the water flow through the unsaturated zone and thereby enable the calculation of aquifer recharge, which occurs through precipitation. One part of the Zagreb aquifer recharge occurs through infiltration from precipitation. In order to observe and model infiltration from precipitation through the unsaturated zone, the research polygon was constructed at the Velika Gorica well field, located in the southern part of the Zagreb aquifer, Croatia, where hourly measurements of electric conductivity (EC) and soil moisture content were carried out. EC and soil moisture data are measured by Time Domain Reflectometry (TDR) probes which are placed at different depths in the unsaturated zone. Furthermore, electrical resistivity tomography (ERT) measurements were conducted. Geophysical data, along with moisture and EC data from TDR probes, were used as input data for MoisturEC software, in order to obtain soil moisture distribution along a 2D profile. MoisturEC program offers three options for translating EC data to moisture content data which are all tested in this research. We obtained eight moisture content distributions along the observed profile and concluded that MoisturEC provides reasonable results with input data from geophysical measurements and TDR probe measurements. Soil moisture distribution in the unsaturated zone represents the initial conditions for further unsaturated flow modeling. Understanding the flow in the unsaturated zone enables the quantification of effective infiltration and can improve groundwater management.
{"title":"Mapping of soil moisture by time domain reflectometry and electrical resistivity tomography at Velika Gorica well field, Zagreb aquifer","authors":"Laura Bačani, Kristijan Posavec, F. Šumanovac, Josipa Kapuralić","doi":"10.15233/gfz.2022.39.13","DOIUrl":"https://doi.org/10.15233/gfz.2022.39.13","url":null,"abstract":"Knowing the soil moisture distribution in the unsaturated zone can improve understanding the water flow through the unsaturated zone and thereby enable the calculation of aquifer recharge, which occurs through precipitation. One part of the Zagreb aquifer recharge occurs through infiltration from precipitation. In order to observe and model infiltration from precipitation through the unsaturated zone, the research polygon was constructed at the Velika Gorica well field, located in the southern part of the Zagreb aquifer, Croatia, where hourly measurements of electric conductivity (EC) and soil moisture content were carried out. EC and soil moisture data are measured by Time Domain Reflectometry (TDR) probes which are placed at different depths in the unsaturated zone. Furthermore, electrical resistivity tomography (ERT) measurements were conducted. Geophysical data, along with moisture and EC data from TDR probes, were used as input data for MoisturEC software, in order to obtain soil moisture distribution along a 2D profile. MoisturEC program offers three options for translating EC data to moisture content data which are all tested in this research. We obtained eight moisture content distributions along the observed profile and concluded that MoisturEC provides reasonable results with input data from geophysical measurements and TDR probe measurements. Soil moisture distribution in the unsaturated zone represents the initial conditions for further unsaturated flow modeling. Understanding the flow in the unsaturated zone enables the quantification of effective infiltration and can improve groundwater management.","PeriodicalId":50419,"journal":{"name":"Geofizika","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49612636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The temperature of a small elongated lake (2.3 km by 0.1-0.6 km; maximum depth of 46 m) located in a mountaneous area was measured during July-September period over three years (2018-2020) at the depth close to the lake surface (0.2 m). Concurrent standard meteorological variables were measured in the vicinity of the lake. Criteria based on atmospheric and lake conditions were defined to detect the days with persistent lake-land breeze (LLB) events. The results showed that 17.7% of the investigated days were associated with LLB events. These days were accompanied by elevated energy in the normalized wavelet spectra for the wind speed at period of 24 hours. Daytime onshore lake breezes were mainly channeled in the along-lake direction due to the surrounding topography. Accordingly, during the daytime, diurnal wind veering was distorted. However, during the nighttime, a clear clockwise wind rotation was present. In addition, the results exhibited a clear relationship between the lake-land temperature difference and the strength of the LLBs.
{"title":"Lake-land breezes over a small elongated lake (Kozjak, Plitvice Lakes, Croatia)","authors":"Darko Staver, H. Mihanovic, Zvjezdana B. Klaić","doi":"10.15233/gfz.2022.39.11","DOIUrl":"https://doi.org/10.15233/gfz.2022.39.11","url":null,"abstract":"The temperature of a small elongated lake (2.3 km by 0.1-0.6 km; maximum depth of 46 m) located in a mountaneous area was measured during July-September period over three years (2018-2020) at the depth close to the lake surface (0.2 m). Concurrent standard meteorological variables were measured in the vicinity of the lake. Criteria based on atmospheric and lake conditions were defined to detect the days with persistent lake-land breeze (LLB) events. The results showed that 17.7% of the investigated days were associated with LLB events. These days were accompanied by elevated energy in the normalized wavelet spectra for the wind speed at period of 24 hours. Daytime onshore lake breezes were mainly channeled in the along-lake direction due to the surrounding topography. Accordingly, during the daytime, diurnal wind veering was distorted. However, during the nighttime, a clear clockwise wind rotation was present. In addition, the results exhibited a clear relationship between the lake-land temperature difference and the strength of the LLBs.","PeriodicalId":50419,"journal":{"name":"Geofizika","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41296537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Yasuda, A. Fenta, Hidetoshi Miyazaki, S. Ishiyama, K. Inosako, A. Din, T. Kawai
In the central dry zone of Myanmar, the mean annual rainfall is less than 1000 mm. Although rainfed agriculture is commonly practiced there, the feasibility of rainfed farming is compromised by the large fluctuations of rainfall and the frequent occurrence of dry years. The monthly distribution of rainfall follows a bimodal pattern. The intensity of the monsoonal rainfall from May to October is characterized by two peaks, an early peak (May-June) and a late peak (August–October), separated by the inter-monsoon (July). The return times of dry and wet years make management of rainfed agriculture problematic. There is very little correlation between the early and late monsoonal rainfall (r=–0.257). However, monsoonal rainfall is teleconnected to sea surface temperatures (SSTs) in certain areas of the Pacific Ocean in real time. Furthermore, at lag times of 6–9 months, there are teleconnections between the early monsoonal, inter-monsoonal, and late monsoonal rainfall and SSTs in certain areas of the Indian Ocean and Atlantic Ocean. We used an Elman artificial neural network model to predict early monsoonal, inter-monsoonal, and late monsoonal rainfall based on teleconnections with SSTs in the Indian and Atlantic oceans 6–9 months before the rainfall occurred. The correlation coefficient between the predicted and observed rainfall exceeded 0.7 in all three cases.
{"title":"Prediction of bimodal monsoonal rainfall in the central dry zone of Myanmar using teleconnections with global sea surface temperatures","authors":"H. Yasuda, A. Fenta, Hidetoshi Miyazaki, S. Ishiyama, K. Inosako, A. Din, T. Kawai","doi":"10.15233/gfz.2022.39.9","DOIUrl":"https://doi.org/10.15233/gfz.2022.39.9","url":null,"abstract":"In the central dry zone of Myanmar, the mean annual rainfall is less than 1000 mm. Although rainfed agriculture is commonly practiced there, the feasibility of rainfed farming is compromised by the large fluctuations of rainfall and the frequent occurrence of dry years. The monthly distribution of rainfall follows a bimodal pattern. The intensity of the monsoonal rainfall from May to October is characterized by two peaks, an early peak (May-June) and a late peak (August–October), separated by the inter-monsoon (July). The return times of dry and wet years make management of rainfed agriculture problematic. There is very little correlation between the early and late monsoonal rainfall (r=–0.257). However, monsoonal rainfall is teleconnected to sea surface temperatures (SSTs) in certain areas of the Pacific Ocean in real time. Furthermore, at lag times of 6–9 months, there are teleconnections between the early monsoonal, inter-monsoonal, and late monsoonal rainfall and SSTs in certain areas of the Indian Ocean and Atlantic Ocean. We used an Elman artificial neural network model to predict early monsoonal, inter-monsoonal, and late monsoonal rainfall based on teleconnections with SSTs in the Indian and Atlantic oceans 6–9 months before the rainfall occurred. The correlation coefficient between the predicted and observed rainfall exceeded 0.7 in all three cases.","PeriodicalId":50419,"journal":{"name":"Geofizika","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45095916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The study examines spatiotemporal distribution of fire weather conditions during the fire seasons of 1990–2020 in the mixed forests areas of the territory of Belarus and Ukraine using monthly mean Fire Weather Index (FWI) averaged for each administrative area in the study region. It was revealed that the lowest FWI values were observed in the northern and northwestern regions of Belarus, the highest values were in the southeast. On the territory of Ukraine, FWI values increase toward the east regions. In the seasonal distribution, the FWI increases from March to May and in the middle of summer the index reaches a maximum in the all regions. Analysis of the FWI dynamics over the five-year periods showed that the frequency of danger fire weather conditions varied from a "very low" level to "moderate" level most of the study period. In the last pentad 2015–2020, "high" fire danger level began to appear in the south of Belarus and in the northern part of Ukraine. During the study period, in some regions of Ukraine, there was a decrease in the frequency of the FWI values of 'low' danger level and its simultaneous increase at the higher levels, in connection with the observed climate change in the region.
{"title":"Dynamics of fire weather conditions in the mixed forest areas of Belarus and Ukraine under recent climate change","authors":"I. Semenova, Katsiaryna M. Sumak","doi":"10.15233/gfz.2022.39.10","DOIUrl":"https://doi.org/10.15233/gfz.2022.39.10","url":null,"abstract":"The study examines spatiotemporal distribution of fire weather conditions during the fire seasons of 1990–2020 in the mixed forests areas of the territory of Belarus and Ukraine using monthly mean Fire Weather Index (FWI) averaged for each administrative area in the study region. It was revealed that the lowest FWI values were observed in the northern and northwestern regions of Belarus, the highest values were in the southeast. On the territory of Ukraine, FWI values increase toward the east regions. In the seasonal distribution, the FWI increases from March to May and in the middle of summer the index reaches a maximum in the all regions. Analysis of the FWI dynamics over the five-year periods showed that the frequency of danger fire weather conditions varied from a \"very low\" level to \"moderate\" level most of the study period. In the last pentad 2015–2020, \"high\" fire danger level began to appear in the south of Belarus and in the northern part of Ukraine. During the study period, in some regions of Ukraine, there was a decrease in the frequency of the FWI values of 'low' danger level and its simultaneous increase at the higher levels, in connection with the observed climate change in the region.","PeriodicalId":50419,"journal":{"name":"Geofizika","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48038355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Raghupratim Rakshit, D. Bezbaruah, Farha Zaman, Bubul Bharali, Sowrav Saikia
Northeast India is a geodynamic hotspot for tectonic activities where three different plates viz., Indian, Eurasian and Burma Plates collide and deform with respect to each other. Northeast moving Indian Plate subducting transversely beneath Burma Plate results in the formation of the Indo-Burmese Ranges (IBR). In central IBR, the north-south trending Churachandpur-Mao Fault (CMF) is situated in the east of the Mizoram-Tripura Fold belt. The northwest-southeast trending Mat River Fault or Mat Fault (MF), which is another major crustal-scale strike-slip transverse fault, upholds the movement of the CMF. In this work, seismotectonic analysis of these two active intra-plate faults which are related to the June-September 2020 earthquake series, have been discussed. It is observed from satellite imageries, earthquake data and confirmed by the field investigation that these faults are not directly involved in the generation of the earthquakes; rather epicenters are distributed in the junction between the MF and CMF. It is evident from the seismotectonic analysis that this stress is distributed through some northwest-southeast synthetic faults, located north of MF and parallel to it, close to the junction with the CMF. The focal solution of the strongest of the 2020 earthquakes, the 5.5 Mw Champhai earthquake (on 22nd June 2020 at 04:10 IST) in Mizoram shows that the principal nodal plane was aligning along MF. Therefore, it is these synthetic faults that are responsible for the earthquakes rather than the locked zone between intra-plate MF and CMF crustal faults. This juxtaposition has caused a major shift in the geodynamic regime in the central IBR. Champhai earthquake might not be the only large devastating earthquake in the region and could be followed by more major earthquakes in the future.
{"title":"Locked crustal faults associated with the subducting Indian Lithosphere and its implications in seismotectonic activity in the Central Indo-Burmese Ranges, Northeast India","authors":"Raghupratim Rakshit, D. Bezbaruah, Farha Zaman, Bubul Bharali, Sowrav Saikia","doi":"10.15233/gfz.2022.39.5","DOIUrl":"https://doi.org/10.15233/gfz.2022.39.5","url":null,"abstract":"Northeast India is a geodynamic hotspot for tectonic activities where three different plates viz., Indian, Eurasian and Burma Plates collide and deform with respect to each other. Northeast moving Indian Plate subducting transversely beneath Burma Plate results in the formation of the Indo-Burmese Ranges (IBR). In central IBR, the north-south trending Churachandpur-Mao Fault (CMF) is situated in the east of the Mizoram-Tripura Fold belt. The northwest-southeast trending Mat River Fault or Mat Fault (MF), which is another major crustal-scale strike-slip transverse fault, upholds the movement of the CMF. In this work, seismotectonic analysis of these two active intra-plate faults which are related to the June-September 2020 earthquake series, have been discussed. It is observed from satellite imageries, earthquake data and confirmed by the field investigation that these faults are not directly involved in the generation of the earthquakes; rather epicenters are distributed in the junction between the MF and CMF. It is evident from the seismotectonic analysis that this stress is distributed through some northwest-southeast synthetic faults, located north of MF and parallel to it, close to the junction with the CMF. The focal solution of the strongest of the 2020 earthquakes, the 5.5 Mw Champhai earthquake (on 22nd June 2020 at 04:10 IST) in Mizoram shows that the principal nodal plane was aligning along MF. Therefore, it is these synthetic faults that are responsible for the earthquakes rather than the locked zone between intra-plate MF and CMF crustal faults. This juxtaposition has caused a major shift in the geodynamic regime in the central IBR. Champhai earthquake might not be the only large devastating earthquake in the region and could be followed by more major earthquakes in the future.","PeriodicalId":50419,"journal":{"name":"Geofizika","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48192881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：