Subjects -> METEOROLOGY (Total: 106 journals)
 Showing 1 - 36 of 36 Journals sorted alphabetically Acta Meteorologica Sinica       (Followers: 4) Advances in Atmospheric Sciences       (Followers: 45) Advances in Climate Change Research       (Followers: 50) Advances in Meteorology       (Followers: 27) Advances in Statistical Climatology, Meteorology and Oceanography       (Followers: 11) Aeolian Research       (Followers: 7) Agricultural and Forest Meteorology       (Followers: 20) American Journal of Climate Change       (Followers: 37) Atmósfera       (Followers: 2) Atmosphere       (Followers: 33) Atmosphere-Ocean       (Followers: 16) Atmospheric and Oceanic Science Letters       (Followers: 13) Atmospheric Chemistry and Physics (ACP)       (Followers: 43) Atmospheric Chemistry and Physics Discussions (ACPD)       (Followers: 15) Atmospheric Environment       (Followers: 72) Atmospheric Environment : X       (Followers: 3) Atmospheric Research       (Followers: 73) Atmospheric Science Letters       (Followers: 40) Boundary-Layer Meteorology       (Followers: 32) Bulletin of Atmospheric Science and Technology       (Followers: 5) Bulletin of the American Meteorological Society       (Followers: 63) Carbon Balance and Management       (Followers: 6) Ciencia, Ambiente y Clima       (Followers: 1) Climate       (Followers: 8) Climate and Energy       (Followers: 6) Climate Change Economics       (Followers: 44) Climate Change Responses       (Followers: 23) Climate Dynamics       (Followers: 45) Climate Law       (Followers: 6) Climate of the Past (CP)       (Followers: 6) Climate of the Past Discussions (CPD)       (Followers: 1) Climate Policy       (Followers: 51) Climate Research       (Followers: 9) Climate Resilience and Sustainability       (Followers: 21) Climate Risk Management       (Followers: 10) Climate Services       (Followers: 4) Climatic Change       (Followers: 69) Current Climate Change Reports       (Followers: 17) Dynamics and Statistics of the Climate System       (Followers: 6) Dynamics of Atmospheres and Oceans       (Followers: 19) Earth Perspectives - Transdisciplinarity Enabled       (Followers: 1) Economics of Disasters and Climate Change       (Followers: 13) Energy & Environment       (Followers: 24) Environmental and Climate Technologies       (Followers: 3) Environmental Dynamics and Global Climate Change       (Followers: 21) Frontiers in Climate       (Followers: 4) GeoHazards       (Followers: 2) Global Meteorology       (Followers: 20) International Journal of Atmospheric Sciences       (Followers: 25) International Journal of Biometeorology       (Followers: 3) International Journal of Climate Change Strategies and Management       (Followers: 29) International Journal of Climatology       (Followers: 28) International Journal of Environment and Climate Change       (Followers: 20) International Journal of Image and Data Fusion       (Followers: 3) Journal of Agricultural Meteorology Journal of Applied Meteorology and Climatology       (Followers: 42) Journal of Atmospheric and Oceanic Technology       (Followers: 33) Journal of Atmospheric and Solar-Terrestrial Physics       (Followers: 133) Journal of Atmospheric Chemistry       (Followers: 23) Journal of Climate       (Followers: 56) Journal of Climate Change and Health       (Followers: 4) Journal of Climatology       (Followers: 4) Journal of Hydrology and Meteorology       (Followers: 39) Journal of Hydrometeorology       (Followers: 10) Journal of Integrative Environmental Sciences       (Followers: 4) Journal of Meteorological Research       (Followers: 2) Journal of Meteorology and Climate Science       (Followers: 21) Journal of Space Weather and Space Climate       (Followers: 30) Journal of the Atmospheric Sciences       (Followers: 83) Journal of the Meteorological Society of Japan       (Followers: 7) Journal of Weather Modification       (Followers: 4) Mediterranean Marine Science       (Followers: 2) Meteorologica       (Followers: 2) Meteorological Applications       (Followers: 4) Meteorological Monographs       (Followers: 1) Meteorologische Zeitschrift       (Followers: 4) Meteorology and Atmospheric Physics       (Followers: 29) Mètode Science Studies Journal : Annual Review Michigan Journal of Sustainability       (Followers: 1) Modeling Earth Systems and Environment       (Followers: 1) Monthly Notices of the Royal Astronomical Society       (Followers: 13) Monthly Weather Review       (Followers: 30) Nature Climate Change       (Followers: 145) Nature Reports Climate Change       (Followers: 40) Nīvār       (Followers: 1) npj Climate and Atmospheric Science       (Followers: 6) Open Atmospheric Science Journal       (Followers: 6) Open Journal of Modern Hydrology       (Followers: 5) Revista Iberoamericana de Bioeconomía y Cambio Climático       (Followers: 1) Russian Meteorology and Hydrology       (Followers: 4) Space Weather       (Followers: 27) Studia Geophysica et Geodaetica       (Followers: 1) Tellus A       (Followers: 21) Tellus B       (Followers: 20) The Cryosphere (TC)       (Followers: 8) The Quarterly Journal of the Royal Meteorological Society       (Followers: 32) Theoretical and Applied Climatology       (Followers: 14) Tropical Cyclone Research and Review       (Followers: 1) Urban Climate       (Followers: 5) Weather       (Followers: 20) Weather and Climate Dynamics       (Followers: 1) Weather and Climate Extremes       (Followers: 18) Weather and Forecasting       (Followers: 43) Weatherwise       (Followers: 18) 气候与环境研究       (Followers: 2)
Similar Journals
 Modeling Earth Systems and EnvironmentNumber of Followers: 1      Hybrid journal (It can contain Open Access articles) ISSN (Print) 2363-6203 - ISSN (Online) 2363-6211 Published by Springer-Verlag  [2469 journals]
• Assessing long-term coral reef degradation in Indonesia’s Tiworo strait
marine conservation area using remote sensing and rapid appraisal for
fisheries approaches

Abstract: In Indonesia, the coral reef ecosystem in the Tiworo Strait Conservation Area (TSCA) faces various threats of natural and anthropogenic stressors that can damage the coral reef ecosystem's role and services. We analyzed changes in coral reef habitat at TSCA over the 25 years from 1994 to 2019 using multi-temporal and multi-sensor satellite imagery data combined with in-situ measurement data and social surveys. Our results show a decrease in live coral cover from 78.30 ha in 1994 to 8.01 ha in 2019, with a 2.81 ha/year degradation rate. Our analysis of 37 threat attributes shows that the TSCA coral reef ecosystem faces a “high threat” to very high threat levels. Threat scores for coral reefs assessed as facing severe conditions according to threat indices included contributions from the ecological dimension (16.87 = very high threat), economic dimension (31.00 = high threat), social dimension (34.83 = high threat), technological dimension (41.10 = high threat), and law and institutional dimension (26.83 = high threat). Coral reefs will undoubtedly go extinct if local threats continue without preventative measures. Therefore, the sustainability of coral reefs in the TSCA—one of the most important marine conservation sites in the Coral Triangle Marine Eco-region should be the primary priority for all stakeholders. Appropriate policies and supervision in the field must be carried out rigorously and measurably, implementing the analyzed set of strategies.
PubDate: 2022-05-16

• Assessment of the hydrological impact of land use/cover changes in a
semi-arid basin using the SWAT model (case of the Oued Saïda basin in
western Algeria)

Abstract: Algeria is considered a country at risk in the index of vulnerability to climate change. In terms of water resources, there has been a significant decrease in water supply in the western part for three decades. This has led to changes in agricultural practices and the viability of natural species, as well as socio-political conditions and anthropogenic action at the watershed scale, which directly affect the water cycle. This study aims to quantify the impact of land use/land cover change on the hydrological response of the Oued Saida basin using the Swat model from 1998 to 2005. Satellite image time series of 1987 and 2002 were used for land use and cover from. A supervised classification approach, using the maximum likelihood classification method was used for the land cover of 1987 and 2002. In addition, post-classification was made to detect changes in land use/land cover. FAO soil data 30 m spatial resolution ASTER DEM data and 1998 to 2005 climate data set were combined as input data to the SWAT model land cover map (2002), with. First for the calibration phase, then those from 1987 was incorporated into the model as the scenario used for the assessment of land use change impacts. Evaluation of the accuracy of classified images was made with the error matrix. The global precision (the kappa coefficient) found for the 1987 (2002) image is 89.5% (95.9%). As a result, evolutionary analysis of land use change from 1987 to 2002 showed a decrease in agricultural area (9.20%), an increase in forest land (5.42%) and an increase in urbanized areas (2.77%). The results of the model calibration using the SWAT-CUP software’s SUFI-2 algorithm were satisfactory with a Nash Sutcliffe (NSE) efficiency coefficient of 0.56 and an R2 of 0.57. In addition, parameters related to soil properties and land use are the most sensitive. Changes in land cover have affected the runoff, increasing the average annual (monthly) peak flow by 2.5 to 3.5% (0 to 6%) at the expense of the seepage water and groundwater recharge. These changes are explained by socio-economic, political and anthropogenic conditions. The results obtained provide useful information about observed and land use trends and affected hydrological behaviors and can be a tool to assist decision-making in the development and management of the catchment area in a global vision.
PubDate: 2022-05-16

• Evaluation of dry and wet spell events over West Africa using CORDEX-CORE
regional climate models

Abstract: This study investigates the capability of regional climate models (RCMs) in simulating four extreme precipitation indices on an annual and monthly scale over West Africa during the period 1997–2014. Three global climate models (GCMs; HadGEM2-ES, NorESM1 and MPI-ESM) were dynamically downscaled using three high resolution ( $$0.22^{\circ }$$ ) regional climate models (RCMs; RegCM4, REMO2015 and CCLM5-0-15). These simulations were from the Coordinated Output for Regional Evaluations within the Coordinated Regional Climate Downscaling Experiment framework (CORDEX-CORE) publicly available through the Earth System Grid Federation (ESGF) web portals. The capabilities of the RCMs in the representation of maximum consecutive wet day (CWD), maximum consecutive dry days (CDD), number of dry days (NDD), and number of wet days (NWD) were compared with observation/satellites datasets obtained from the Global Precipitation Climatology Project (GPCP), Tropical Rainfall Measuring Mission (TRMM) and Tropical Applications of Meteorology using SATellite data and ground-based observations (TAMSAT). The reference datasets showed similar spatial pattern and magnitude of analyzed precipitation extremes but models exhibit different pronounced discrepancies relative to them. All RCMs consistently captured the spatial patterns of the indices but with some pronounced biases along the Guinean coast and northern parts of Niger. There exists little or no biases in the representation of annual cycle along the Guinea and Sahel for all the indices based on each of the RCMs ensemble, with the exception of RegCM4 which has a more pronounced bias in CWD. Statistical evaluation of the performance of the models over the entire West Africa with respect to the 4 indices revealed that REMO2015 models and its ensemble have overall lowest root mean square error followed by the choice of MPI-ESM GCM downscaled with either of the RCMs. REMO-HAD was found to have the best performance in the representation of consecutive dry days and number of wet days with RMSE values of 25.74 and 18.91 respectively. REMO-MPI has superior performance in the estimation of consecutive wet days and number of dry days with RMSE values of 5.38 and 20.51 respectively. Generally, REMO RCMs ensemble was found to be the best ensemble in all indices except consecutive dry days where REG4 ensembles had better performance. Operational use of these 3 RCMs are recommended with compensation for over-and underestimations.
PubDate: 2022-05-14

• Comparison of two open-source digital elevation models for 1D hydrodynamic
flow analysis: a case of Ozat River basin, Gujarat, India

Abstract: The Ozat River originates from the Gir forest in the Junagadh district, and the river mouth is near Navi Bandar in the Porbandar district. Before meeting the Arabian sea, the river splits into two portions; one flows towards Ghed region, while the other flows straight towards Pata village; before the separation, water is scattered throughout the low-lying terrain, which is frequent. This research aims to compare the open-source digital elevation model (DEM) for 1D hydrodynamic flow analysis, river stage analysis along the reaches from inflow to river mouths, and the calibration of Manning roughness value. This study boosts researcher’s capability to work with open-source DEM. Shuttle Radar Topography Mission (SRTM) 30 m and Advanced Land Observing Satellite (ALOS) 30 m DEMs carried with Hydrologic Engineering Centre River Analysis System for 1-Dimensional hydrodynamic analysis. For the comparative study of DEMs, there are two criteria emphasized (1) Water Surface Elevation (WSE) and (2) Cross-Section Inundation. Specific places are set for WSE changes, and all reach is considered for the cross-section inundation study. Regression analysis was employed to calculate root mean square error (RMSE) for water surface elevation changes and coefficient of determination (R2) for the cross-section inundation study. The result shows RMSE values are 0.34 and 1.31 for water surface elevation changes, R2 values are 0.81 and 0.59 for an inundation of cross sections, respectively, for SRTM and ALOS. It shows that the lower value of RMSE and a better R2 value of SRTM DEM made a close agreement with an observed data set. Most split stretches seem inundated on both river bank sides, according to the one-dimensional model. Ground survey and Unmanned Aerial Vehicle photographs have enhanced a support system for decision-makers.
PubDate: 2022-05-14

• Modelling the recent variations of water balance components and water
availability within the Senegal River basin: using WEAP21 model

Abstract: The availability of water in the Senegal River basin is a basic issue for moving towards efficient resource management. Given the extent of the river and the large number of stations, hydrological modelling is a reliable means of assessing the evolution of the water balance and availability over the last 30 years. This paper aims to evaluate water balance components and to model the water balance over the Senegal River basin from 1989 to 2020. The streamflow data have been calibrated and validated with the PEST program incorporated in WEAP with a NSE equal to 0.98, a PBIAS of 7% and a R2 of 0.98. The water balance has been computed using the Soil Moisture Method which use mainly climate data and runoff data to output different results driving to an analysis of the water balance components. The results have shown that the precipitation is the main alimentation of the river with a mean rainfall of 267,255.84 Mm3; the losses by evapotranspiration are 246,892.45 Mm3. According to the conventional formula, the water balance would be equal to 20,363.38Mm3 in the Senegal River basin. The modelling of the water balance in this basin will allow a further study concerning the effect of climate change on the hydrological and ecological system of the Senegal River basin. A variation in the resource and hydrological parameters was noted. Although the 30 years see a decrease in rainfall, runoff increases. However, it remains to integrate the water use parameters for better conclusions.
PubDate: 2022-05-14

• Inhomogeneous Poisson point process for species distribution modelling:
relative performance of methods accounting for sampling bias and imperfect
detection

Abstract: Species distribution models (SDMs) have become tools of great importance in ecology, as advanced knowledge of suitable species habitat is required for the process of global biodiversity conservation. Presence-only data are the more abundant and readily available data widely used in SDM applications. These data should be treated as a thinned Poisson process to account for detection errors related to sampling bias and imperfect detection that arise in them. Failure to do so could be detrimental to SDM’s predictions. This study assesses the effects of the species abundance, the variation in detection probability, and the number of sites visited in planned surveys on the performance of SDMs accounting for detection errors using simulated data. The results show that the accuracy and precision of estimates differ depending on models and species abundance. Their main difference lies in their ability to estimate $$\beta _0$$ , the model intercept. The lower the species abundance, the higher the bias and variance of $$\hat{\beta _0}$$ . Furthermore, the lower the detection probability, the higher the bias and variance of $$\hat{\beta _0}$$ . However, $$\beta _1$$ , the slope parameter, is estimated with almost high accuracy and precision for all models. This study demonstrates the low efficiency of accounting for sampling bias and imperfect detection based on presence-only data alone. Analysing presence-only data in conjunction with point-count outperformed the other approaches, whatever the species abundance, as long as the detection probability is at least 0.25 with average values of detectability covariates. The acceptable accuracy and precision, the minimum number of sites to consider vary depending on species abundance. At least 200 sites are required for the rare species, whereas 50 sites can suffice for the abundant species. Since collecting high-quality data are very expensive, this study emphasizes the need to promote initiatives such as citizen science programs that aim to collect species occurrence data with as little bias as possible.
PubDate: 2022-05-11

• Evaluation of the hydrology and sediment load situations of the upper
watershed of Thac Ba reservoir (Vietnam and China) under the impacts of
climate changes

Abstract: The Thac Ba reservoir serves as a critical supply of water for residents in Hanoi's downstream region, who rely on it for their livelihood. Recent changes in land use have resulted in a greater input of silt and nutrients into the environment. A large number of modeling studies have not been carried out because of the challenges in obtaining data from both China and Vietnam. The reservoir is located inside an international drainage basin that connects China and Vietnam. On the basis of the findings of the calibrated and verified SWAT model on streamflow and sediment, we provide this paper. On the basis of monthly data gathered from 1992 to 2003, the model’s performance was extremely excellent in terms of the coefficient of determination (R2) and the Nash–Sutcliffe coefficient (NSE), with R2 = 0.885 and NSE = 0.914 for precipitation and R2 = 0.826 and NSE = 0.849 for sediment, respectively. It was less accurate (NSE = 0.628) but remained dependable in the daily streamflow calibration case study. Based on climate change predictions for Vietnam, four scenarios were designed and assessed for this study. The case study also provides a quantitative illustration of how successfully GIS and SWAT can function together when the amount of meteorological data available is restricted. These findings will be useful in the administration of water and soil conservation initiatives in the future.
PubDate: 2022-05-11

• Geophysical and geochemical prospecting for submarine groundwater
discharge in a karst leaky aquifer from Valliyur Hills to Uvari Beach

Abstract: Coastal freshwater aquifer characteristic study is essential for drinking water and domestic purpose. SGD of groundwater flux study was carried out using geophysical methods such as Azimuthal square array resistivity, 2D electrical resistivity imaging (ERI), magneto-telluric and geochemical analysis of water samples. In the square array method, the resistivity of fractured/ faulted zone with leaky aquifer of SGD is identified using resistivity variations. The 2D ERI techniques apparent resistivity values changes and pseudo-section colour difference are used for SGD flow path. Magneto-telluric method is a tool for SGD flow in the subsurface karst topography with differentiating flow of depth. The grain size analysis of beach sediments as fine sand is encountered in the statistical analysis of grain sorting. The deeper aquifer location is identified using square array and magneto-telluric method layer by layer. The magneto-telluric resistivity profiles observation of aquifer thickness, soil, and rock hydraulic conductivity, the gradient of flow using Darcy’s law was used to estimate the flux of the Uvari beach SGD flow rate. The geochemical phases of freshwater samples U2, U3, U4 U6, U7, U8, U9 mixing of HCO3 and seawater intrusion in U1, U5 in Mix SO4 concentration is found in the study.
PubDate: 2022-05-10

• RescueNet: YOLO-based object detection model for detection and counting of
flood survivors

Abstract: Floods are the common and frequent type of major natural disasters, having a large-scale economic impact on the country causing widespread damage, resulting in loss of life and damages to both public and personal property. Between 1998–2018, floods affected more than 2 billion people worldwide. Humans don't have much influence over preventing this natural calamity, but a mitigation measure can be taken to rescue the lives under such critical circumstances. But can plan ahead of time for rescue operations in the impacted areas to move people and animals to a safer location where time is very critical. When the environmental conditions are adverse or non-supportive, it is difficult to detect humans and animals using conventional approaches. Accurate, in time detection and immediate provision of life saving measures are the key to rescue the survivors during disastrous situation. Unmanned Aerial Vehicles (UAV's) can be used to collect real-time images from low altitude airspace to get the aerial view of the images which in turn supports vast emergency rescues. The major challenge wit this is to dynamically process huge amount of data to identify and locate such affected people in real time. Due to significant development in Deep learning technologies, object detection in UAV images that aims to identify humans and animals can be accomplished. This paper proposes a Deep-learning based efficient emergency response model [RescueNet] for helping Rescue system in detecting survivors in flood devastated regions during response activities. Results obtained from the implementation of the proposed model shows the effectiveness of the model in detecting and counting the affected people and animals. The model shows a precision of 0.98, recall of 0.97, an F1-score of 0.94 and means average precision (mAP) of 98% which significantly proved that, the proposed model could certainly help the rescue system in providing the on-time response for saving lives.
PubDate: 2022-05-07

• Transboundary shear aquifers in arid zones for sustainable development:
case study Gabghaba between Egypt and Sudan

Abstract: Gabghaba transboundary shear aquifer between South Egypt and North Sudan east Lake Nasser is a good example of the shear aquifer. It is highly affected by the Keraf Shear zone and fault systems that play important roles in the accumulation of ~ 800 m groundwater and connection with surface water bodies. The Nubian Sandstone aquifer system is the main aquifer that is divided into Lower Cretaceous (Sabaya and Abu Simbil) and Paleozoic aquifers from top to bottom. Sabaya is the top unconfined aquifer and has a thickness reach of ~ 210 m and is directly connected with Lake Nasser and River Nile. It has salinity from ~ 180 to ~ 1115 ppm and is isotopically depleted. Abu Simbil unconfined to confined aquifer has a thickness of about 370 m, salinity from ~ 1100 to 2200 ppm, is more chemically evolved, and is isotopically more depleted. The Paleozoic unconfined to unconfined aquifer has thickness reach to 200 m with probable salinity from 1500 to 3000 ppm. The Nubian aquifer is a hydraulic connection through fault systems and facies, the water table flow trend is from the SSE to the NNW and the groundwater salinity is the opposite related to the impact of recharge from Lake Nasser and River Nile, where the groundwater salinity decrease from ~ 2200 ppm in the southern part to ~ 180 ppm near Lake Nasser. The study encourages prospecting shear aquifers elsewhere for reducing water scarcity and food shortage.
PubDate: 2022-05-06

• Customization of GIS for spatial and temporal analyses of Air Quality
Index trends in Kabul city

Abstract: The capital of Afghanistan, Kabul city, is in the ranking of severely polluted metropolitan cities and air pollution becomes a controversial issue especially in cold months of winter season. Air quality and environment are affected by anthropogenic and natural activities. Moreover, seasonal variations also influence the concentration level of air pollution. It is essential to control and alleviate air pollution in incredibly polluted areas of the city. Due to the limited number of mobile air quality monitoring stations by National Environmental Protection Agency (NEPA) of Afghanistan in Kabul city, using spatial interpolation tool in GIS, predicts air pollution concentration at unmonitored locations by means of which we can achieve important information about the dispersion of air pollution. In the present study, GIS-based spatial modelling of air pollution is carried out for the comparison of Air Quality Index trends in terms of six criterion air pollutants PM 2.5, PM 10, SO2, NO2, CO, and O3 in Kabul city during 2019–2020. For the parallel forecast of AQI at un-sampled locations, inverse distance weighting (IDW) interpolation technique was used in ArcMap 10.8. This study’s finding indicated spatial and temporal variation in AQI followed almost same trends during study period. Kabul city experienced good air quality in summer months of April and May of study period and AQI was in good and moderate category and in winter months, AQI fluctuated between unhealthy and hazardous categories.
PubDate: 2022-05-06

• Sensitivity analysis of CN using SCS-CN approach, rain gauges and TRMM
satellite data assessment into HEC-HMS hydrological model in the upper
basin of Oum Er Rbia, Morocco

Abstract: Abstract Hydrological process modelling consistency is associated with long available gauged data and reliable parameters, which is often limited. Multi-sensors and satellite-based products are considered as an alternative, especially dealing with ungauged basins. In this study, a HEC-HMS hydrological model is used to test two rainfall dataset reliability (Gauges, TRMM product). The testing period is fixed for 2000–2011 to simulate streamflow generated at upper Oum Er Rbia basin. Dealing with soil information lack in the study, we implemented SCS-CN approach in its spatially semi distributed manner, adjusting CN, and comparing streamflow obtained by interpolated gauged and average TRMM pixels values, the model was calibrated to determine its accurate CN for the study area. In the calibration phase, the analysis of CN sensitivity shows its importance on direct flow simulation and for HEC-HMS results. Moreover, the optimal value for the study area is ranging between 30 and 40. In addition, the elaborated model is showing slightly sufficient performance when using TRMM precipitation data at a daily time scale even though its overestimations during intense precipitation events. As a conclusion, the model validation results show an instability estimation for simulated daily streamflow at the upper Oum Er Rbia basin.
PubDate: 2022-04-29

• Spatial variability of soil properties determined by the interpolation
methods in the agricultural lands

Abstract: Abstract Geostatistical methods are widely applied to determine the spatial variability of soil parameters in the unknown points, as their main benefit to classical statistics, through incorporating limited measured data. The objective of the present research was to investigate the spatial variability of various soil parameters determined by different geostatistical methods including ordinary kriging (OK) and radial basis function (RBF) in the east of the Karun River, south of Ahvaz, Iran for the purpose of recommending fertilization practices. A total of 250 soil samples (0–30 cm) were randomly collected from the study area and were analyzed for pH, salinity (EC), available potassium (AK), CaCO3, sand, silt, and clay. The precision of the prepared maps was determined by the cross-validation analysis using root mean square error (RMSE), mean absolute error (MAE), mean bias error (MBE) and Q–Q plot. The C.V. values indicated the highest spatial distribution for EC (49.4%), AK (39.6%) and sand (56%). However, the pH variable had a little variability (C.V. of 3.7%), and clay (24.7%) and silt (21%) had moderate variability. The variogram analyses indicated the effective ranges for pH (610.9), EC (255.7), AK (253.16), CaCO3 (31.6), sand (611), silt (254) and clay (252). According to the results RBF method could provide higher precision for EC, CaCO3, sand, and silt, and OK is a more precise technique for the estimation of pH, AK, and clay. Such results could be applied for the proper handling of agricultural lands and increasing the efficiency of yield production by recommending efficient fertilization techniques.
PubDate: 2022-04-27

• Earlier green-up and senescence of temperate United States rangelands
under future climate

Abstract: Abstract Climate and vegetation phenology are closely linked, and climate change is already impacting phenology in many systems. These impacts are expected to progress in the future. We sought to forecast future shifts in rangeland growing season timing due to climate change, and interpret their importance for land management and ecosystem function. We trained a model on remotely sensed land surface phenology and climate data collected from 2001 to 2014 in temperate United States rangelands. We used this model to forecast annual growing season start dates, end dates, and season length through 2099 among six general circulation models and under RCP 4.5 and 8.5 scenarios. Growing season start was projected to shift earlier throughout our study area. In 2090–2099, start of season advanced by an average of 10 (RCP 4.5) to 17 (RCP 8.5) days. End of season also advanced by 12 (RCP 4.5) to 24 (RCP 8.5) days, but with greater heterogeneity. Start and end of season change mainly offset one another, so growing season length changes were lesser (2 days in RCP 4.5, and 7 in RCP 8.5). Some mountainous areas experienced both earlier start of season and later end of season, lengthening their growing season. Earlier phenology in rangelands would force adaptation in grazing and impact ecosystem function. Mountainous areas with earlier start and later end of season may become more viable for grazing, but most areas may experience slightly shortened growing seasons. Autumn phenology warrants greater research, and our finding of earlier autumn senescence contradicts some prior research.
PubDate: 2022-04-27

• An investigation into the future changes in rainfall onset, cessation and
length of rainy season in the Oti River Basin, West Africa

Abstract: Abstract The study determined rainfall onset and cessation dates, and length of rainy season (LRS) in the Oti River Basin (ORB) using historical data (1981–2010) and future (2021–2050) model data. Historical data were from meteorological stations, Climate Hazards Group Infrared Precipitation with Stations (CHIRPS) and National Aeronautics and Space Administration Prediction of Worldwide Energy Resource (NASA POWER) while ensemble of eight models were acquired from Coordinated Regional Climate Downscaling Experiment (CORDEX-Africa). An evaluation of the models was performed based on correlation, standard deviation and root-mean-square error (RMSE). The onset, cessation and LRS were analyzed for trends using the Mann–Kendall test and Sen’s slope estimator. An evaluation of the performance of the models on rainfall revealed strong correlation (r > 0.9), with standard deviation < 2.0 and RMSE < 0.75 whereas for temperature a strong correlation (r ≥ 0.99), standard deviation < 1.25 and RMSE < 0.25 were also recorded. Results also showed that onset date could increase from 8 May (128 days) to about 24 May (144 days) in the future under the Representative Concentration Pathways (RCPs) emission scenarios. Cessation date which was on 29 October (302 days) in the historical period could decrease to 7 October (280 days) under both RCP4.5 and RCP8.5 scenarios in future. The LRS would decrease from 173 days to about 136 days under both emission scenarios. These anticipated variations in onset and cessation dates, and LRS are amongst the important rainfall characteristics that could affect future agricultural viability and planning, and the availability of water in the ORB.
PubDate: 2022-04-26

• Groundwater flow evaluation using a groundwater budget model and updated
aquifer structures at an alluvial fan of Echi-gawa, Japan

Abstract: Abstract As groundwater is a vital water resource and plays an important role in sustainable use and environment maintenance, evaluating the groundwater flow is crucial. To quantitatively ascertain the groundwater flow at the Echi-gawa alluvial fan, Japan, groundwater budget was carried out by combining hydrogeological parameters (hydraulic gradient, hydraulic conductivity, and recharge rate) and modified aquifer structures (unconfined/confined aquifers and aquitards). The groundwater budget was calculated on the right bank (B–B′ cross section) and left bank (C–C′ cross section) of the Echi River, where the aquifer structures are significantly different. The total flow rate in the unconfined aquifer was 533.2 × 103 m3/year, of which the outflow to the confined aquifer was 14% in B–B′, whereas the total flow rate in the unconfined aquifer was 433.7 × 103 m3/year, of which the outflow to the confined aquifer was 2.7% in C–C′. The difference of the outflow to the confined aquifer between B–B′ and C–C′ is derived from the difference of the updated aquifer structures. The groundwater budget indicated that 5–20-holds amount of the groundwater infiltrates to more deeper aquifers than the aquitard the study targeted near the foot of mountains. The groundwater pumping in the confined aquifer in B–B′ affects the infiltration of the unconfined aquifer, which may control the groundwater quality. Results of the groundwater budget in this study are well corresponded to the previous studies. Although separating the groundwater pumping and the upward groundwater flow rate using the groundwater budget this study provided is unavailable due to lack of the hydraulic head in ATI in C–C′, the method used for this study is adequate to reproduce groundwater flow systems, which may be applicable to areas, where the aquifer structures are unestablished.
PubDate: 2022-04-26

• Application of HEC–HMS for runoff simulation of Gojeb Watershed,
Southwest Ethiopia

Abstract: The objective of this study is to apply HEC–HMS for hydrological modeling of the Gojeb watershed. The daily precipitation and stream flow, Land Use Land Cover (LU/LC), soil, and Digital Elevation Model (DEM) were the data used to achieve the objective. The sensitivity analysis of the watershed parameters showed that Curve Number (CN), initial abstraction ratio (λ), and lag time (tlag) were most sensitive, whereas wave travel time (K) and channel storage coefficient (x) were moderately sensitive. The sensitivity of these parameters signifies that LU/LC, soil types, topography, and channel geometry, which are the dominant runoff causative factors, are lumped by these parameters. Model calibration and validation were conducted from 2002 to 2008 and 2009 to 2014, respectively. The selected objective functions during the calibration and validation periods were PEP (Percentage Error in simulated Peak), PEV (Percentage Error in simulated Volume), Nash–Sutcliffe efficiency (NSE), Root Mean Square Error (RMSE), Percent bias (PBIAS), and Coefficient of Determination (R2). Their respective values during the calibration period were 16.44%, 10.3%, 0.81, 10.42m3/s, 11.64% and 0.87; and during the validation period, 3.92%, 22.95%, 0.551, 12.85 m3/s, 22.91% and 0.73. The result showed that HEC–HMS well simulated the daily runoff of the Gojeb watershed. The average monthly observed and simulated flow during the entire simulation period were 1,044.9m3/s and 841.4m3/s, respectively, whereas the annual average observed and simulated runoff values of the watershed were 12,538.8 m3/s and 10,096.8m3/s, respectively. Hydrological modeling of the Gojeb watershed helps to better understand the effect of watershed management practices on surface runoff. The HEC–HMS model can also be used for water scarce areas with limited data or for ungauged watersheds.
PubDate: 2022-04-26

• Application of revised universal soil loss equation model for assessment
of soil erosion and prioritization of ravine infested sub basins of a
semi-arid river system in India

Abstract: Abstract Soil is an integral part of Earth’s ecosystem. Topographic and climatic factors play an important role in influencing the complex process of soil erosion. Lithological formation, elevation, slope steepness, soil texture, land-use and land-cover constitute the primary topographic factors and rainfall constitutes the major climatic factor. Soil erosion in India's semiarid regions results in soil fertility loss as well as a slew of other significant environmental consequences, posing a threat to the region's long-term agricultural production and river health. Revised Universal Soil Loss Equation (RUSLE) and Geographic Information System (GIS) constitute a very successful technique to assess soil erosion. The present study assessed soil erosion, specific sediment yield and quantified the yearly rate of soil loss in the ravine infested Kunwari River basin, a part of the Yamuna-Chambal Badlands region, India. RUSLE model, integrated with geospatial techniques is useful for soil loss estimation, prioritization of sub basins and their implications on land use in this ravine infested area. Rainfall, soil, satellite imagery, and DEM data derived the model factors. The annual estimated soil loss varied from 0 to 176.9 42 t ha−1 year−1 with a total annual soil loss of 4,260,929.52 t year−1 and a mean soil loss of 6.42 t ha−1 year−1 from the entire catchment. The result shows the annual average sediment yield is 1.22 t ha−1 year−1 and the total volume of the sediment yield for Kunwari basin is 8,09,576.61 t year−1. Since the bulk of the area has rugged and dissected, the topographical factors play a major role in the results which shows higher rates of soil erosion. The result of sub-basin prioritization indicates that sub-basin Sb 5, Sb 8 and Sb 9 are found to be under the high priority zone. The findings of the study based on RUSLE and GIS offer a precise appraisal of soil loss, identifying the priority areas which can be helpful in designing and executing effected policies for sustainable soil management practice to prevent soil erosion.
PubDate: 2022-04-25

• Application of HEC-HMS for Hydrological Modeling of Upper Sabarmati River
Basin, Gujarat, India

Abstract: Abstract Hydrological modeling works as an efficient tool to predict the hydrological response of the watershed with the intent to devise strategies for the efficient management of water. The overarching intent of this study was to use an HEC–HMS model to simulate rainfall-runoff processes in the Upper basin of Sabarmati River, Gujarat. The hydro-meteorological data required for the study were collected from the State Water Data Centre, Gandhinagar and the India-WRIS portal. The SCS-Curve Number method, SCS unit hydrograph method, Muskingum routing method, and recession method were applied to model the infiltration loss, transforming the rainfall excess into surface runoff, flow routing of the channel reach and baseflow model. The Digital Elevation Model (DEM) of 30 m resolution, the soil map from FAO portal, and the land use/land cover (LULC) map of India were processed on GIS platform using an extension tool HEC-GeoHMS. The data for the period 2001–2010 were used for calibration, whereas the validation was carried out using the 2011–2015 data. The performance analysis was done on two criteria—Coefficient of Determination (R2) and Nash–Sutcliffe Efficiency (NSE) and was carried out for three sub-basins whose discharge were available. For Vautha sub-basin, R2 was 0.88 and NSE was 0.84 during calibration. During validation the value of R2 and NSE were was 0.87 and 0.84, respectively. The model performed well for the other two sub-basins, namely, Jotasan and Kheroj during both the calibration and the validation stage. The results of the research clearly show the potentiality of the proposed model in adequately simulating the stream-flows in the basin. Thus, it can be culminated that the proposed HEC–HMS model can efficiently model the rainfall-runoff processes in the Upper Sabarmati River, thus leading to efficient management of the available water resources in the basin.
PubDate: 2022-04-25

• Geophysical investigation of groundwater potential zones, and modeling of
subsurface materials using seismic refraction surveys

Abstract: Abstract Delineation of zones with the potential of bearing groundwater is important for the efficient exploration and extraction of groundwater. In this paper, the seismic refraction method was used as a primary approach for groundwater exploration. In this regard, seismic refraction surveys were conducted along two traverse lines of lengths 155 m and 140 m. Along each traverse line, forward and reverse shots were induced with 32 sampling points (geophones). The velocities of the subsurface layers were obtained and each layer thickness was computed. Subsequently, subsurface models of the investigated sites were built. The generated models clearly showed the lateral and vertical variations in various subsurface materials expected as well as the layer thicknesses. The results for traverse line one revealed three distinct layers with velocities ranging between 470.10 and 1623.50 m/s and thicknesses ranging between 0 and 51.67 m. Similarly, three different layers were observed in traverse line two with velocities ranging between 463.35 and 4050.31 m/s and thicknesses ranging from 0 to 46.67 m. Findings from this study also revealed a high groundwater potential in the study area. In addition, the results of this study correlated well with existing borehole logs in the study area. This observation further strengthens the reliability of the obtained results. This study might be useful in the efficient delineation of potential zones for groundwater occurrence through the modeling of subsurface layers (materials).
PubDate: 2022-04-25

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