Subjects -> METEOROLOGY (Total: 110 journals)
 Showing 1 - 36 of 36 Journals sorted alphabetically Acta Meteorologica Sinica       (Followers: 3) Advances in Atmospheric Sciences       (Followers: 43) Advances in Climate Change Research       (Followers: 28) Advances in Meteorology       (Followers: 24) Advances in Statistical Climatology, Meteorology and Oceanography       (Followers: 7) Aeolian Research       (Followers: 6) Agricultural and Forest Meteorology       (Followers: 18) American Journal of Climate Change       (Followers: 27) Atmósfera       (Followers: 3) Atmosphere       (Followers: 25) Atmosphere-Ocean       (Followers: 14) Atmospheric and Oceanic Science Letters       (Followers: 10) Atmospheric Chemistry and Physics (ACP)       (Followers: 47) Atmospheric Chemistry and Physics Discussions (ACPD)       (Followers: 14) Atmospheric Environment       (Followers: 72) Atmospheric Environment : X       (Followers: 3) Atmospheric Research       (Followers: 69) Atmospheric Science Letters       (Followers: 36) Boundary-Layer Meteorology       (Followers: 31) Bulletin of Atmospheric Science and Technology       (Followers: 1) Bulletin of the American Meteorological Society       (Followers: 49) Carbon Balance and Management       (Followers: 4) Change and Adaptation in Socio-Ecological Systems       (Followers: 4) Ciencia, Ambiente y Clima       (Followers: 3) Climate       (Followers: 5) Climate Change Economics       (Followers: 14) Climate Change Research Letters       (Followers: 7) Climate Change Responses       (Followers: 8) Climate Dynamics       (Followers: 44) Climate law       (Followers: 7) Climate of the Past (CP)       (Followers: 5) Climate of the Past Discussions (CPD) Climate Policy       (Followers: 36) Climate Research       (Followers: 6) Climate Risk Management       (Followers: 4) Climate Services       (Followers: 3) Climate Summary of South Africa       (Followers: 2) Climatic Change       (Followers: 60) Current Climate Change Reports       (Followers: 4) Developments in Atmospheric Science       (Followers: 27) Dynamics and Statistics of the Climate System       (Followers: 5) Dynamics of Atmospheres and Oceans       (Followers: 18) Earth Perspectives - Transdisciplinarity Enabled Economics of Disasters and Climate Change       (Followers: 2) Energy & Environment       (Followers: 23) Environmental and Climate Technologies       (Followers: 4) Environmental Dynamics and Global Climate Change       (Followers: 6) Frontiers in Climate       (Followers: 2) GeoHazards       (Followers: 1) Global Meteorology       (Followers: 17) International Journal of Atmospheric Sciences       (Followers: 21) International Journal of Biometeorology       (Followers: 1) International Journal of Climatology       (Followers: 31) International Journal of Environment and Climate Change       (Followers: 3) International Journal of Image and Data Fusion       (Followers: 2) Journal of Agricultural Meteorology Journal of Applied Meteorology and Climatology       (Followers: 35) Journal of Atmospheric and Oceanic Technology       (Followers: 33) Journal of Atmospheric and Solar-Terrestrial Physics       (Followers: 199) Journal of Atmospheric Chemistry       (Followers: 21) Journal of Climate       (Followers: 54) Journal of Climate Change       (Followers: 2) Journal of Climatology       (Followers: 3) Journal of Hydrology and Meteorology       (Followers: 29) Journal of Hydrometeorology       (Followers: 11) Journal of Integrative Environmental Sciences       (Followers: 4) Journal of Meteorological Research       (Followers: 1) Journal of Meteorology and Climate Science       (Followers: 14) Journal of Space Weather and Space Climate       (Followers: 27) Journal of the Atmospheric Sciences       (Followers: 79) Journal of the Meteorological Society of Japan       (Followers: 6) Journal of Weather Modification       (Followers: 2) Large Marine Ecosystems       (Followers: 1) Mathematics of Climate and Weather Forecasting       (Followers: 6) Mediterranean Marine Science       (Followers: 1) Meteorologica       (Followers: 2) Meteorological Applications       (Followers: 4) Meteorological Monographs Meteorologische Zeitschrift       (Followers: 3) Meteorology and Atmospheric Physics       (Followers: 26) Mètode Science Studies Journal : Annual Review Michigan Journal of Sustainability       (Followers: 1) Modeling Earth Systems and Environment Monthly Notices of the Royal Astronomical Society       (Followers: 14) Monthly Weather Review       (Followers: 34) Nature Climate Change       (Followers: 125) Nature Reports Climate Change       (Followers: 35) Nīvār npj Climate and Atmospheric Science       (Followers: 3) Open Atmospheric Science Journal       (Followers: 2) Open Journal of Modern Hydrology       (Followers: 6) Revista Brasileira de Meteorologia Revista Iberoamericana de Bioeconomía y Cambio Climático Russian Meteorology and Hydrology       (Followers: 3) Space Weather       (Followers: 24) Studia Geophysica et Geodaetica Tellus A       (Followers: 22) Tellus B       (Followers: 21) The Cryosphere (TC)       (Followers: 5) The Cryosphere Discussions (TCD)       (Followers: 4) The Quarterly Journal of the Royal Meteorological Society       (Followers: 27) Theoretical and Applied Climatology       (Followers: 12) Tropical Cyclone Research and Review       (Followers: 1) Urban Climate       (Followers: 4) Weather       (Followers: 19) Weather and Climate Dynamics Weather and Climate Extremes       (Followers: 16) Weather and Forecasting       (Followers: 28) Weatherwise       (Followers: 4) 气候与环境研究       (Followers: 1)
Similar Journals
 Modeling Earth Systems and EnvironmentNumber of Followers: 0      Hybrid journal (It can contain Open Access articles) ISSN (Print) 2363-6203 - ISSN (Online) 2363-6211 Published by Springer-Verlag  [2626 journals]
• The influence of global climate drivers on monsoon onset variability in
Nigeria using S2S models
• Abstract: Abstract Rainfall onset has a lot of implications on the sustainability of the socio-economic activities in Nigeria. This study assesses the skills of CMA, ECMWF, and UKMO sub-seasonal-to-seasonal (S2S) models in predicting monsoon onset and its variability over Nigeria. It also investigates the global drivers modulating the variability and their teleconnections with rainfall onset anomaly. All the models, their ensemble members, and the observations were subjected to quantitative statistical analyses from 1998 to 2016. Results show that the three models are able to simulate the Northwards migration of the onset dates adequately with inherent biases and unique characteristics. They are also able to capture the evolution and variability of the global drivers modulating the monsoon onset. While CMA and the ECMWF models improve progressively towards the Sahel, the UKMO model performance is best over the Gulf of Guinea. In addition, despite the fairly poor performance of the models in predicting the variability of onset dates over the Gulf of Guinea and the Sahel, there is a considerable improvement in the correlation skill of the models over the Savannah. Furthermore, results show that only the ECMWF model was able to produce the strength of both the African Easterly Jets (AEJ) and the Tropical Easterly Jet (TEJ) in spatio-temporal mode. These are two of the crucial global drivers modulating the dynamics of West African monsoon. It was also found out that most global drivers, especially the Inter-tropical Discontinuity (ITD) and the Sea Surface Temperature (SST) over the Central Pacific, exhibit direct teleconnection with the onset anomaly. This direct relationship is shown to be strongest over both the Gulf of Guinea and the Sahel. Although the CMA model might have the least skill, it, however, showed that all the S2S models, despite the inherent biases, are able to predict rainfall onset over Nigeria, within the sub-seasonal timescale. Finally, the results show that improvements in multi-model ensembles are valuable added information able to significantly improve model performance.
PubDate: 2019-12-01

• Assessment of inundation risk in urban floods using HEC RAS 2D
• Abstract: Abstract Flood is the most common natural disaster upsetting the highest population of the world. In recent times, severe floods in urban areas are occurring more frequently owing to uncontrolled urbanization and climate change and it will continue to grow in upcoming years. Prevention of such events is not possible but with advancement of technology, flood-vulnerable areas can be identified through 2-D modeling of critical rainfall events. The difficulty associated with urban floods is unpredictable flow conditions in urban environment due to rapid alterations in topography and unavailability of extensive raw dataset. Thus, modeling of urban floods becomes a complex process. A vast number of numerical models have evolved over the past few years which are capable of flood mapping; most of them are commercial, rigorous and need extensive dataset to generate precise results. This paper presents a simple sophisticated approach to analyze extreme rainfall events based on past critical events and synthetic hyetographs developed from IDF curves for a part of Hyderabad, India. HEC-RAS, a freely available 2-D hydraulic model with integration to GIS is used to generate depth of flood inundation over underlying terrain and risk maps of flood inundation are developed for different rainfall scenarios. The model results identify 17% of total area is liable to floods out of which 9% area indicates high risk, 52% area shows medium risk and remaining 35% area falls under low risk of flooding.
PubDate: 2019-12-01

• Channel degenerations and hydraulic shrinkages implicated by anthropogenic
interference as a temporal outcome: a study of Magurmari River,
Darjeeling, India
• Abstract: Abstract The study of fluvial processes deals with the fluid of natural origin through a channel that carries particulate sediments including solid load either in solution, or in suspension and even rolling over the channel bed. Channel bed forms, cross-sectional shapes, channel geometry, etc. have direct interactions among flow, sediment, and the channel boundaries and any untoward reaction through anthropo-geogenic activity to disrupt the riverine ecology can lead to degenerations of channel. The present work has been focused to analyze the impact of anthropo-geographic implications on river habitat change through hydro-geomorphological study. The river Magurmari flowing through the Sub-Himalayan foothills of Darjeeling is of such kind which is degenerating and decaying over time and is losing its vivacity. The main objective of the work is to find out the interrelations of the hydraulic parameters as indicators of level of degeneration in view of their natural setup especially rainfall regime and head water supply. Field works with leveling surveys to draft the cross sections and measurement of hydraulic characteristics have carried out by the authors. Empirical formulae have been calculated to find the results and to analyze their interrelations. Moreover, map works have been done under GIS environment as the allied methodological attempts. Finally, findings on river habitat Survey through rating magnitudes in Likert scale and hydraulic impact study have been done.
PubDate: 2019-12-01

• Investigating the hydrogeochemical processes and quality of water
resources in Ojoto and environs using integrated classical methods
• Abstract: Abstract In an attempt to determine their suitability for consumption and irrigation uses, the prevailing hydrogeochemical processes and quality of both surface and groundwaters in Ojoto province, southeastern Nigeria were studied. Classical scientific methods and indicators such as hydrogeochemistry, stoichiometry, water quality index (WQI), and multivariate statistical analyses were integrated to achieve the research objectives. pH results classified most of the waters as slightly acidic. The order of dominance of the major cations and anions is Na+ > Ca2+ > K+ > Mg2+ and SO42– > Cl– > NO3– > HCO3–, respectively. The dominant water type is Na–Ca–SO4, and the dominant water facies in the area is sodium sulphate (Na–SO4), constituting about 54% of the total samples. Several hydrogeochemical, stoichiometric, and multivariate statistical analyses revealed that both anthropogenic inputs and geogenic processes (such as precipitation, silicate weathering, oxidation, and ionic exchange) influence the chemistry and quality of the waters. WQI of the waters showed that only 17.86% of the analyzed samples are of good quality for drinking purposes, whereas the quality of 53.57, 17.86, and 10.71% of the samples is poor, very poor, and unfit for use, respectively. Various irrigation suitability assessments (including salinity hazard, sodium absorption ratio, sodium percentage, residual sodium carbonate, chloro-alkaline indices, magnesium hazard, Kelly’s ratio, permeability index, and potential salinity) conducted revealed that majority of the analyzed waters have poor irrigation quality.
PubDate: 2019-12-01

• Using geographic information system (GIS) modeling in evaluation of canals
water quality in Sharkia Governorate, East Nile Delta, Egypt
• Abstract: Abstract Pollution in freshwater canals is given a great interest due to its bad impacts on humans, animals and fish wealth. The objective of this research is to formulate a methodology to help water planner and water resources engineers for sufficient use of water to avoid harmful impacts from polluted water in Sharkia Governorate in East Nile Delta. Therefore, 59 water samples were collected from different locations along with the canals network. Canals water quality variation is detected using a weighted spatial overlay method inside geographic information system software (GIS). Accordingly, the weighted spatial water quality model (WSWQM) was performed inside the GIS system to determine spatial variation in water quality of the studied canals. Ten effective water quality parameters for the collected water samples were used as thematic layers to build the WSWQM model. These parameters include; total dissolved solids, pH, water hardness, dissolved oxygen, biological oxygen demand, chemical oxygen demand, nitrate, fluoride, ammonium, and fecal colon bacteria. The WSWQM was run and a water quality map was resulted and classified the studied canals into five classes ranging from very low to very high-water quality. High and very high-water quality classes are observed in the southern parts of the study area, whereas the low and very low classes are represented by the northern parts of the study area at ends of the studied canals. The obtained results may assist in providing a detailed overview of the polluted reaches of the studied canals, which help in the management process for this important water source.
PubDate: 2019-12-01

• Land use and land cover changes in Doume Communal Forest in eastern
Cameroon: implications for conservation and sustainable management
• Abstract: Abstract Large-scale identification of land use and land cover change in a tropical forest is a challenge to landscape designers and forest ecologists. Here, Landsat images acquired during the years 2000, 2009, and 2018 were used to assess the spatial-dynamics of land use and land cover (LULC) during the last two decades (2000–2018). A classification system composed of six classes—dense forest with (high tree density and low tree density), swampy Raphia forest, swampy flooded forest and savanna were designed as LULC for this study. A maximum likelihood classification was used to classify Landsat images into thematic areas. Elsewhere, Landsat-based LULC mapping, post classification at the per-pixel scales and self-knowledge on the land cover change processes were combined to analyze LULC change, forest loss and change trajectories in Doume Communal Forest in eastern Cameroon. The results show that half of the study area changed in 2000–2009 and that the different types of LULC changes increased and involved more diverse and characteristic trajectories in 2009–2018 compared to 2000–2009. Degradation to a dense forest with low tree density and swampy Raphia forest was dominant, and the forest was mostly lost due to trajectories that involved conversion to agroforestry systems (10%), and a lesser extent due to trajectories that involved deforestation to grasslands (7%). The trajectory analyses did thus contribute to a more comprehensive analysis of LULC change and the drivers of forest loss and, therefore, is essential to improve the sustainable management and support spatial planning of the forest.
PubDate: 2019-12-01

• Developing GIS based Coastal Water Quality Index for Rameswaram Island,
India positioned in Gulf of Mannar Marine Biosphere Reserve
• Abstract: Abstract This paper employs widely used Water Quality Index (WQI), which synthesizes biological and physiochemical parameters into one single number that can be straightforwardly understood by decision makers and public. Rameswaram Island is one of the highly populated Islands of India, embraces with density of economically/ecologically important species and is most significantly located between Palk Bay and Gulf of Mannar. Water quality data obtained from 25 sampling sites around Rameshwaram Island between April 2011 and March 2012. The key parameters included for development of Water Quality Index were pH, temperature, turbidity, suspended solids, dissolved oxygen and biochemical oxygen demand using multiplicative water quality index. WQI lies in the “Good” category for all the seasons except summer, which falls under “Moderate”. Station 5B shows “Moderate” WQI in all the seasons because of the pilgrimage and tourism activities as well as the settlement at Rameswaram discharging municipal sewage. The use of the indices on a continuous basis provides long-term data which is helpful for decision making and management.
PubDate: 2019-12-01

• Dynamic response of monsoon precipitation to mineral dust radiative
forcing in the West Africa region
• Abstract: Abstract Mineral dust over West Africa region modulates summer monsoon through direct radiative forcing. This study examined the impact of mineral dust radiative forcing on West Africa Monsoon variability with the aid of Regional Climate Model (RegCM4) at 50 km grid resolution driven by ERA Interim re-analysis. Three experiments were performed; first with the non-dust aerosol version of the model (CONTROL), and second with the dust aerosol module (DUST) and with an increase in the dust concentration (DOUBLE DUST). The simulation was run from October, 2004 to December, 2005 over West Africa domain with the first 3 months taken as spin up for model stability. The result shows that there was no significant change with Control and Dust case experiment but as the dust AOD increases from 1.0 to 2.0, radiation flux at the Top of Atmosphere changes from − 60 to − 80 W/m2 in the Double dust experiment. The Surface Long-wave Radiation Flux of 8.0 W/m2 remains unchanged in both cases. The Outgoing Long-wave Radiation (OLR) flux changes from 2.0 to 4.0 W/m2 indicating reduction in convective formation and as well as decrease in precipitation of 2 mm/day in the Sahel, while precipitation increases from 2 to 4 mm/day in the Guinea coast region. There was also strengthening of TEJ core and weakening of AEJ above average as dust concentration increases in some parts of the region during the monsoon period. The air temperature increases from 22.5 to 38.5 °C in both cases from coastal area to Sahelian region of West Africa. It was concluded that substantial amount of dust concentration in the atmosphere could trigger and increase radiative forcing of aerosols thereby sensitive to monsoon variability and results in enhancement of precipitation amount in the Guinea coast and reduction of precipitation amount in the Sahel region of West Africa. Meanwhile, there is need to inquire more into difference aerosol concentration per specie that can trigger or increase radiative forcing in the atmosphere.
PubDate: 2019-12-01

• Skill of CMIP5 models in simulating rainfall over Malawi
• Abstract: Abstract Unravelling future projections of precipitation at the local scale is vitally important for building a climate-resilient economy and for the formulations of National Policies on Climate Change. Central to the entire discipline of climate projections is the use of models. However, model performance varies from one region to another. Therefore, the goal of this study is to examine the performance of 18 Coupled Model Intercomparison Project Phase 5 (CMIP5) historical simulations of precipitation over Malawi against rain gauge data. The period of study runs from 1982 to 2005. Statistical analyses were extensively carried out at both spatial and temporal scales using the following metrics: correlation coefficient (R), bias, percentage bias (PBias), standard deviation (STDEV), root mean square error (RMSE), and trend. At spatial scales, Hovmoller diagrams (HD) were used to analyse model simulations. Results indicate that the models adequately reproduce the expected annual cycle of rainfall although ~ 77% of them overestimate rain gauge data. Further, only nine of the models analysed correlate positively with rain gauge data. The correlation ranges from − 0.2 to 0.43. Seasonal root mean square errors (RMSEs) are largest during the core of the rainy season (December–February), the beginning (September–October), and the end (March–May), respectively. Rainy gauge data showed that the highest standard deviation was in the north-eastern parts of the country and around the Lake Malawi region. In general, most models poorly simulated the spatial standard deviation. Although there are large variations in model performance, models that generally perform better than others are: CNRM-CM5, EC-EARTH, GISS-E2-H, and MPI-ESM-LR. While these models are identified as well performing, their deficiencies have also been extensively discussed in this work, and therefore, caution needs to be exercised by end users when using these models to make decisions pertaining to climate change adaptation and mitigation strategies.
PubDate: 2019-12-01

• Influence analysis of peak rate factor in the flood events’ calibration
process using HEC–HMS
• Abstract: Abstract In flood management, analysis and modelling are needed, especially for the analysis of the occurrence of floods and decision making. One method for analyzing flood events can use the HEC–HMS software. In HEC–HMS, there are three sub-models, namely, losses, transform, and baseflow. In the development of the use of the HEC–HMS model, it still utilizes sub-model transform, where the peak rate factor (PRF) value is constant at 484 in modelling. The value of PRF is very dependent on the slope of the land (basin slope), where the value of this parameter is very varied depending on the physical condition of the area under study. Because of the fact, where the value of PRF should be varied depends on the slope in modelling stage; while the reality is still constant, this research is done. The research result shows that the role of PRF makes the modelling carried out using HEC–HMS produce comparable results as indicated by the objective function values in two study areas. The following is the comparison of the objective function of the Selorejo watershed in the March 2007 flood event between constant PRF 484 with variations in the values of PRF, RMSE (0.63 m; 0.59 m), CORREL (0.977; 0.976), and DELTAPEAK (43.04%; 41.46%). Whereas in the PDA Cipasang watershed, Nash–Sutcliffe (0.818; 0.820), RMSE (66.20 m3/s; 65.91 m3/s), CORREL (0.916; 0.917), and DELTAPEAK (15.55%; 15.35%). To utilize the variation of PRF into the model, based on the results of this study, the sub-model used is SCS Curve Number for Losses, SCS Units Hydrograph for Transform, and Recession Constant for Baseflow. It can be concluded that by including the influence of variations in PRF values resulting not a better model but only a slight improvement which is insignificant and a more complete model.
PubDate: 2019-12-01

• Simulation of extreme event-based rainfall–runoff process of an urban
catchment area using HEC-HMS
• Abstract: Abstract Flood is ranked as the deadliest natural disaster that has been experienced by the urban basins in the world. Its detrimental effects can be minimized by appropriate modeling, analysis and management methods. Such modeling and analysis techniques help in flood risk assessment predicting flood occurrence, aid in the emergency preparation for evacuation and reduce damage from the impact of floods. Numerous modeling techniques are available for analyzing flood events, of which HEC-HMS software is chosen for this explorative study because of its simplicity and as it is a freely available open-source software. The present study aims to develop a rainfall–runoff simulation model by generating peak flow and volume of the extreme rainfall event that occurred on 22 November 1999 in the ungauged Koraiyar basin located south of Tiruchirappalli City in South India. The hydrographs are generated for the basin by using specified hyetograph and frequency storm method to identify the best method to be adopted in the study. Digital elevation model processed with geographic information system (GIS) and HEC-Geo HMS, which is an extension of GIS, is used for the analysis. Using the terrain processing tools in ArcGIS, the basin delineation and parameters such as slope and river length are extracted from the basin. The data generated during the HEC-Geo HMS process are the hydrologic parameters of Koraiyar basin, and it is imported to HEC-HMS modeling for generating peak flow and volume. In the modeling process, HEC-HMS has three modules, namely transform, loss and base flow. SCS curve number and SCS unit hydrograph are used to determine the losses and transformation of rainfall into the runoff process in the present study. The SCS method is adopted because of its simplicity and requirement of limited data approach for modeling. The peak flow and volume prepared from the model are compared with the standard Nash–Sutcliffe values. The frequency storm method has a Nash value of 0.7, which is higher than the value obtained from the specified hyetograph process, and it is chosen as a better model for generating flood peak and volume for different return periods in the basin. It can therefore be adopted for other studies of similar basin conditions.
PubDate: 2019-12-01

• Identification of the trend in precipitation and temperature over the
Kabul River sub-basin: a case study of Afghanistan
• Abstract: Abstract Precipitation and temperature are the two important factors which have more influence and role in climate change as well as hydrology cycle; therefore in this research, the fluctuating trends of rainfall and temperature of the Kabul River basin, Afghanistan, at eight different stations are analyzed. The annual and monthly data were used to detect the trends of precipitation, whereas for temperature trend the maximum and minimum annual data were used. Precipitation data from 2000 to 2018 for eight different metrological stations of the Kabul River basin were analyzed to find the changes in rainfall trend, while for temperature data from the five available weather stations for a period from 2008 to 2018 were used. Temporal precipitation and temperature variation were calculated on monthly and annual intervals. Mann–Kendall and Sen’s slope method was used for the trend analysis, which supports nonparametric statistical analysis. The trend of annual precipitation was calculated over 18 years for all stations. After trend analysis of precipitation with Mann–Kendall test and Sen’s slope, the result showed the increasing precipitation trend of 4.88–30.42 mm/year, as well as the minimum temperatures have increased significantly at a different rate of (−0.02) to (0.71) °C/year. The outcome of the present study may be useful for the water managers to understand the impact of climate change in a sub-basin of Kabul River basin, Afghanistan.
PubDate: 2019-12-01

• Variation of rill cross-sections with gravel and aggregating soil in the
Dry-Hot Valley (SW China)
• Abstract: Abstract Cross-sectional morphology is an effective approach for calculating rill volume and revealing the mechanism for rill development. In this study, the law governing the temporal–spatial variation in rill cross-section (RCS) under interbedded clay and gravel conditions was investigated by a scouring experiment. A high-flow scouring experiment was conducted in a field plot under heterogeneous soil conditions in the Yuanmou Dry-Hot Valley using 3D laser scanning and ArcGIS techniques. Morphological index system including the size and derived proportional parameters was established to accurately reveal the dynamic process of the rill erosion–sediment sections based on temporal–spatial scale. The study indicated that the RCS size under gravel and soil aggregates showed an irregular variation over different periods, and the variation of RCS morphology tends to be nonlinear. The area of rill cross-section at the middle of the rill was much larger than that of the rill head and the rill mouth, and the fluctuations in RCS along the rill depended heavily on the soil texture heterogeneity. In addition, there were extreme variations in rill erosion direction for different rill parts, i.e., rill head, body, and mouth, and the highly significant asymmetry in RCS distributed along the rill under increasing scouring duration in the Yuanmou Dry-Hot valley. Temporal variations in RCS morphology were opposite to spatial variations by comparing the same morphology parameter. Nonlinear fluctuation trends and asymmetric shapes were observed in the variation of RCS on slopes with soils and gravels.
PubDate: 2019-12-01

• Electrical resistivity tomography along the Himalayan Frontal Thrust in
the northwestern Frontal Himalaya for active tectonics studies
• Abstract: Abstract Dependence of ground resistivity upon mineral content, porosity, degree of water saturation in the rock and fluid content makes it ideal for imaging and understanding the subsurface. Results of resistivity imaging, used for active tectonics studies at Kala Amb region in the northwestern Frontal Himalaya are discussed. Study area is selected across the exposed section of the Himalayan Frontal Thrust based on a previous trench excavation survey. An electrical resistivity tomography 2D profile survey is conducted along two lines in Kala Amb region. The lines are selected with the primary objective of extending the features identified in the trench section into the subsurface. The study found to be helpful in understanding the efficacy of this method for the recognition and geometrical characterisation of faults across morphotectonic scarps or fault traces in a region which experienced late Quaternary tectonic activity. The inverted resistivity model has lateral and vertical resistivity variations according to different depositional units in the area. The presence of a north dipping fault at 54-m distance from zero electrode position towards south clearly distinguishes two separate lithological units. The liquefaction feature identified on the trench wall section which is also inferred from the resistivity section appears to be originated from greater depth. Similarity of resistivity features and spatial distance of two profiles allow us to interpret the lateral continuity of subsurface features and to identify the thickness of Quaternary deposit over river bed level.
PubDate: 2019-12-01

• The role of vaccination in curbing tuberculosis epidemic
• Abstract: Abstract This work studies the impact of vaccine in controlling tuberculosis (TB) epidemic using susceptible, vaccinated, exposed, infectious and recovered compartmental model. This is necessitated due to the acclaimed ineffectiveness of BCG vaccine in combatting TB. The model is formulated using a non-linear system of ordinary differential equation which is normalised to eliminate the natural death factor $$(\mu )$$ so as to focus on other factors. The disease-free equilibrium and endemic equilibrium point (EEP) of the system are established alongside their local and global stabilities. Although the local stability of the EEP could not be established analytically due to the cumbersomeness of the EEP obtained, it is, however, established numerically. It is shown with the aid of numerical simulation carried out on the model that vaccination helps in reducing the tuberculosis epidemic and in fact, if the rates of contact and infectivity are reduced, further reduction in the rate of incidence $$(\lambda )$$ can be achieved. Further more, the reason why there is the need for a better vaccine to replace BCG vis-á-vis provision of better immunity coverage $$(\theta \rightarrow 0$$ and $$\sigma \rightarrow 0)$$ and also, the need for the development of drugs that confer permanent or long lasting immunity $$(\delta _2\rightarrow 0)$$ is as well established. More vaccination proportion gives better outcome $$(\tau \rightarrow 1)$$ and the introduced controls show their relevance in reducing the infection. The novelty of this research is the provision of guiding frame work for the pharmacists on the intrinsic features expected of any proposed vaccine to replace BCG while the expected recommendations from the doctors are established using optimal control.
PubDate: 2019-12-01

• Identification of seasonal variation of water turbidity using NDTI method
in Panchet Hill Dam, India
• Abstract: Abstract Sedimentation in reservoir is a common problem in any multipurpose river valley project and is effective upon the performance of it. Every dam has an estimated volume of water holding capacity at the time of inception, but it gradually reduces by siltation. The presence of sediments in water causes turbidity and it slowly precipitates on the floor of the reservoir. Normalized difference turbidity index (NDTI) is a remote sensing technique widely used to identify the water turbidity, which is the ratio of red and green bands of solar spectrum. In Panchet Dam actual rate of siltation exceeds the assumed rate that fills up the entire reservoir area at a faster rate. In this situation, the study has been conducted to explain the variation of water turbidity of the dam throughout the year 2015. Major findings of the study indicate that the turbidity level jumps from 60 NTU to 700 NTU in the monsoon. High turbid water covers 50.57%, 64.22% and 52.79% area of the reservoir in July, August and September, respectively. In contrast, coverage of low turbid water is more than 71.68% in the months of February and June. The medium turbid water covers less than 35.82% area throughout the year except the months of September and October. High level of correlation exists (R2 = 0.900) between NDTI values and total suspended sediments concentration in mg/L (N = 15, p < 0.05) with minimal RMSE (13.59). Variation of seasonal turbidity and different types of turbidity are significant at 95% (p < 0.05) level of significance. The paper is an attempt to probe into the seasonal variation of water turbidity of the dam with the application of NDTI method and related statistical measures.
PubDate: 2019-12-01

• Failure of inland valleys development: a hydrological diagnosis of the
Bankandi valley in Burkina Faso
• Abstract: Abstract Several developed inland valleys for rice production were abandoned due to poor design or implementation. The Bankandi inland valley (BIV) is a contour bunds system developed in 2006 by a development project, currently experiencing a systematic waterlogging. This study assessed: (1) the waterlogging vs. changing hydro-climatic conditions relationship; (2) the hydrological design and implementation of water control infrastructures; and (3) how digital elevation models (DEMs) data could be used for inland valleys development. To investigate the waterlogging vs. changing hydro-climatic conditions (precipitation and discharge), the conceptual HBV model was applied; coupled with break and trend detections tests. To evaluate the accuracy of the location of drainage flume and contour bunds, a topographic survey using a D-GPS was performed. To explore free DEMs as support tool in the development of inland valley, the Shuttle Radar Topography Mission 1 and the Advanced Spaceborne Thermal Emission and Reflection Radiometer 1, were used. The results show that: (1) the waterlogging was not related to changing environmental conditions; (2) major flaws including bunds not implemented on contour lines contribute to the waterlogging; (3) free DEMs were not accurate enough for valley development. The overall diagnostic of BIV entails conducting basic hydrological investigations prior to implementation.
PubDate: 2019-12-01

• Can artificial neural networks estimate potential evapotranspiration in
Peruvian highlands'
• Abstract: Abstract Evapotranspiration (ETo) is one of the most important variables of the water cycle when water requirements for irrigation, water resource planning or hydrological applications are analyzed. In this context, models based on artificial neural networks (ANN) of the retro-propagation type can be an alternative method to estimate ETo in highland regions using a number of input variables limited. The objective of this study is to develop ANN models to estimate ETo for the Peruvian highlands using input variables such as maximum air temperature (Tmax), minimum air temperature (Tmin), hours of sunshine (Sh), relative humidity (Rh) and wind speed (Wv), as an alternative method to FAO Penman–Monteith method (FAO-PM56) and Hargreaves–Samani (HS). Daily climatic datasets recorded at 12 meteorological stations between 1963 and 2015 were selected in this study. For evaluation reason, the ETo calculated using the FAO-PM56 was also considered. The main input variable to ANN modeling is Tmax, followed by Sh and Wv or combinations between them. Hargreaves–Samani (HS) showed a poor performance in the estimation of the ETo in the Peruvian highlands compared to the 13 ANN models. Additionally, it was determined that in stations with lower thermal amplitude (< 14.2 °C) the lowest performance levels are presented in the estimation of the ETo with HS equation, which does not occur markedly with the ANN models that they estimate adequately ETo. Therefore, ANN models represent a great option to replace the FAO-PM56 and HS method, when ETo data series are scarce.
PubDate: 2019-12-01

• The impact of rising temperatures on water balance and phenology of
European beech ( Fagus sylvatica L.) stands
• Abstract: Abstract In this article, we outline the set-up and the application of an eco-hydrological box model, with the aim to describe the water balance of deciduous (Fagus Sylvatica L.) forest stands. The water balance model (WBM) uses standard meteorological parameters as input variables and runs on a daily time step. It consists of two modules. The aboveground module (1) comprises routines for fog precipitation generation, precipitation interception and snowfall/snowmelt dynamics. Covered belowground processes (2) are bypass flow, percolation, soil evaporation and transpiration, where the latter two processes are considered separately. Preceding to the WBM, a routine is introduced, specifying the intra-annual foliage dynamics of beech. Emphasis is also laid on the inter-annual variation of beech phenology. Leaf sprouting and leaf senescence are calculated as functions of day-length and air temperature. The WBM was applied to four European beech dominated forest stands in the northeastern part of Austria. They are located on a gradient of declining annual precipitation (from west to east). The two easterly sites are located close to the (dry) limit of the natural distribution of beech. Records of soil moisture were used for the adjustment of 26 parameters. On all sites the calibration process (simulated annealing) delivered good predictions of soil moisture (Nash–Sutcliffe efficiency ≥ 0.925). Then, the obtained parameterization was used to apply different scenarios of global warming. The temperature was increased step-wisely up to 4 °C. All scenarios were run (1) with present phenological conditions and (2) with phenology responding to higher temperatures. This way, we wanted to assign the effect of higher temperatures and longer growing seasons on the water dynamics of the forest stands. A warming of 1 °C corresponded roughly to an elongation of the growing season of 4.5 days, where the start of the growing season was affected more strongly than the end. Apparently, higher temperatures led to drier soils. The strongest change was observed in early summer, also amplified by an earlier start of the growing season. Rising temperatures led to lower export fluxes of liquid water, simultaneously increasing evapotranspiration (ET). The gain in ET was almost entirely assignable to increased soil evaporation. Drier soils led to a sharp depression of transpiration during summer months. This decline was compensated by the effect of elongated growing seasons. The risk of severe drought was increased by higher temperatures, but here the contribution of growing season length was negligible. Drier soils seem to hamper the stands’ productivity. For all warming scenarios, the estimated increase of the gross primary production, caused by longer periods of assimilation, is nullified by the effect of soil water deficit in mid-summer.
PubDate: 2019-12-01

• Assessment of climate-induced degree of chemical weathering in some
granite and granodiorite slopes of Japan
• Abstract: Abstract The widespread hillslope failures largely depend on the degree of weathering. Different weathering processes, especially chemical weathering, are the consequence of the variation of climatic factors, e.g., temperature and precipitation. The present study describes the various chemical and mineralogical properties of bedrock and soil samples from granite and granodiorite landslide areas under continental temperate, temperate and subtropical climate regions in central to southwestern Japan. The XRD and SEM–EDS analyses were carried out for mineralogical and chemical analyses. It is evident that bedrock samples contain quartz, k-feldspar, plagioclase, biotite and amphibole, whereas the slip surface and the upper surface soil samples are enriched with kaolin minerals, mica clay minerals and vermiculite or 14 Å intergrade minerals. Mobile elements showed decreasing values, whereas immobile elements showed increasing values with progressive weathering due to leaching (dissolution of cations) in all studied areas. The analysis of weathering indices indicated weathering progress in the order from bedrock, slip surface and upper surface soil. The relationship of mean annual air temperature and precipitation for 30 years (1981–2010) with CIA and Si–Al ratio indices showed that CIA values increased and Si–Al ratio decreased with increasing temperature whereas, precipitation did not follow that identical trend. Therefore, temperature is the key factor for chemical weathering in all cases and is more prominent on granodiorite areas than granite areas.
PubDate: 2019-12-01

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