Showing papers in "Journal of Earth Science & Climatic Change in 2018"

Hydrological Responses of Climate Change on Lake Ziway Catchment, Central Rift Valley of Ethiopia

Abstract: This study predicts future runoff conditions under changing climate using multi model outputs from Coupled Model Intercomparison Project Phase 5 (CMIP5) over Lake Ziway Catchment. The River system is located in the Central Rift Valley of Ethiopia which serves for wide range of socio-economic activity, but recently different water use sectors are increasing their pressure on the water balance of the catchment. Bias corrected precipitation, maximum and minimum temperature data from three climate models HadGEM2-ES, CSIRO-MK-3-6-0 and CCSM4 under representative concentration pathways RCP 8.5 and RCP 4.5 were used as input for the hydrologic model. A calibrated and validated HBV model is used to simulate the future inflow from Katar River and Meki River towards Lake Ziway. The result revealed that the maximum and minimum temperature increased under RCP 8.5 and RCP 4.5 scenarios. However, precipitation showed a decreasing trend. The percentage change in monthly average precipitation showed extremes for HadGEM2-ES model which range between -51.19% during January 2050s and +23.15% during February 2080s under RCP 8.5. The model output showed an annual decrement in runoff depth on Katar River up to 19.45% during RCP 8.5 on CSIRO MK-3-6-0 model and maximum reduction was recorded for RCP 4.5 at 17.49% for CCSM4 model. Meki River has shown maximum annual reduction of 20.28% during 2080s on RCP 8.5 for HadGEM2-ES model and seasonally during Bulg maximum increment was recorded for the same model which ranges up to 10.23% on 2050s for RCP 4.5. However seasonal maximum reduction is obtained from Bulg season by 40.27% on HadGEM2-ES model during 2050s. From the study, a reduction in rainfall has brought larger effects on runoff reduction than evapotranspiration components. Due to future reduction of River flow on the region optimal allocations for water use purposes at all levels of water resource development projects are crucial for future water planning and management.

Climate Change Impact on Rainfall and Temperature Distributions Over West Africa from Three IPCC Scenarios

Abstract: The study investigates the climate change impact on monthly and seasonal distribution of rainfall and temperature of three scenarios of the Intergovernmental Panel on Climate Change (IPCC) between year 2000 and 2099. The analysis considered two climatic periods which are 2000 to 2029 as present and 2070 to 2099 as future. The ten-year mean (decadal) analyses of these two parameters were also performed. The result showed that temperature increases over West Africa countries in all the months under each of the scenarios. Scenario A2 with the highest emission of 800 ppm shows the highest increase of temperature and rainfall over West Africa followed by scenario A1B with emission of 720 ppm and the least is that of B1 with the lowest emission of 550 ppm. The result also showed that rainfall increases over most part of West Africa in all the scenarios with the exception of coastline that a little decrease in amount of rainfall was estimated. However, the decadal analysis shows that there is a gradual and almost consistent increase in temperature and rainfall over West Africa. Monthly mean values of scenario B1 estimated higher in all the months than its scenario A1B counterpart while those of A1B are also higher than those of scenario B1. The result implies that the higher the emission, the higher is the temperature which leads to warmer future and most likely the more rainfall and hence likelihood of flooding, more occurrence of heat wave and other high temperature related problems. It therefore recommended that IPCC regulation to reduce emission should be strictly adhered to by all countries so that the world can have a better future to dwell in.

Characteristics of Seasonal Rainfall and its Distribution Over Bale Highland, Southeastern Ethiopia

Abstract: Agricultural productivity heavily depends on onset and cessation of rainfall and Length of Growing Period (LGP). Determining these variables is useful for early warning and preparedness. Therefore, the objective of this study was to show the onset, cessation and LGP of the seasons over Bale Highlands. Bale Highland is characterized by bi-modal rainfall types. In order to find Onset, Cessation and LGP of both Belg and Kiremt seasons, 30 years of rainfall data for periods of (1985 to 2014) in daily format from NMA (National Metrological Agency) Bale robe branch directorate was used. Additionally, for this study, 12 meteorological stations in the Bale Highlands were used. The study shows that there is high variability of onset and cessation in Belg season than kiremt season. The mean onset and mean cessation of Belg season over Bale Highland is March 28 and June 10 with mean standard deviation of 19 days, respectively. On the other hand, in kiremt season, mean onset and mean cessation were July 12 and October 31 with mean standard deviation of 16 and 12 days, respectively. During the major growing season (Kiremt) the mean LGP is 110 days with mean standard deviation of 19 days and for Belg season the mean LGP is 73 days with mean standard deviation of 26 days. The short in LGP and the variation of onset and cessation of the seasons will be considered by the concerned body to aware the local community on the onset and cessation as well as Length of growing period for both seasons. The result found more likely lead the traditional rain-fed agricultural practice in both seasons to shift to irrigation system.

Identification of Meteorological Drought Prone Area in Bangladesh using Standardized Precipitation Index

Abstract: The Standardized Precipitation Index (SPI) was computed in three different cropping seasons namely, Pre-Kharif, Kharif and Rabi based on the monthly precipitation data of thirty-five meteorological stations over Bangladesh during the period 1980–2015. In this study, different features of meteorological drought including frequency of drought, dry and wet periods, percentage of drought area, temporal and spatial variations of drought in Bangladesh were examined. The results revealed that the most significant increasing trend of drought area was found in Rabi season (8.66% per decade) and decreasing trend was found in Kharif season (2.47% per decade). In Kharif season, the trend of drought area was found increasing in northern region with a rate of 2.63% per decade where central region, eastern region and southern and western region were decreasing with a rate of 1.06%, 3.02% and 3.02% per decade, respectively. All drought affected areas were experienced by moderate, severe and extreme droughts in several years during the study period in three seasons. The significant drought events were found in 1992, 2008, 2012 and 2014 in Pre-Kharif, 1981, 1985, 1992, 1994, 2006 and 2012 in Kharif and 1985, 1986, 2005, 2006, 2009, 2010 and 2012 in Rabi season. Some areas of southern and western regions, central regions, eastern regions and most of the northern region were more vulnerable to meteorological drought. Major finding of this study was Pre-Kharif and Rabi season were the most vulnerable to meteorological drought that indicates high seasonal rainfall anomaly in most of the regions of Bangladesh.

Long-Memory and Fractal Trends in Variations of Environmental Radon in Soil: Results from Measurements in Lesvos Island in Greece

Abstract: This paper presents evidence of trends of fractal properties and long memory in three-month variations of radon in soil, in Lesvos Island, Greece. The methodology employed consists of sliding-window (a) detrended fluctuation analysis, (b) fractal analysis, (c) rescaled range analysis and (d) fractal dimension analysis with the methods of Higuchi, Katz and Sevcik. During measurements two mild earthquakes occurred in the vicinity. The results of the detrended fluctuation analysis revealed four peaks with slopes between 1.2 and 1.5. The fractal analysis method resulted in three peaks with persistent power-law exponent values in the range 2.2 and 3.0. The rescaled-range analysis indicated persistent Hurst exponents between 0.7-0.9 and in some segments, between 0.9-1. The fractal dimension analysis showed four peaks with fractal dimensions in the range 1.3-2.0 (Higuchi and Katz methods) and 1.0-1.5 (Sevcik method). The results were compared in terms of conversion to Hurst exponents. Several persistent segments were addressed, along with persistency-anti-persistency switching instances. Potential geological sources are discussed and analyzed.

Application of Remote Sensing for Evaluation of Land Use Change Responses on Hydrology of Muga Watershed, Abbay River Basin, Ethiopia

Abstract: This study deals with impact of land use change on the hydrology of Muga watershed, Ethiopia using remote sensing and the SWAT model. Global sensitivity analysis was used to determine optimal model parameters. Both the calibration and validation was performed using SWAT-CUP and results showed good match between measured and simulated stream flow data with the Nash-Sutcliffe efficiency (NSE) of 0.83, observation standard deviation ratio (RSR) of 0.32 and percent bias (PBIAS) of -10.8% for the calibration, and NSE of 0.79, observation standard deviation ratio (RSR) of 0.54 and percent bias (PBIAS) of -19.8% for the validation period. The overall performance of the model showed that good result. To evaluate land use change impact on hydrology, land use was assigned using six land use classes and processed in ERDAS Imagine and ArcView GIS with the help of ground truth information. Results showed that the area of grass land, shrub land and forest had declined while agricultural land was expanded over the study period. Simulated model results showed an increase of surface runoff in the catchment from 1986 to 2009 while groundwater flow decreased, which is caused due to severe land use changes. By using land use of 2009 as a reference, three scenarios were simulated by changing 5% of each land use (cultivated, grasslands and shrub lands) to forest lands respectively and scenario 1 suggested as best land use scenario to alleviate water resources degradation problem. Citation: Demeke GG, Andualem TG (2018) Application of Remote Sensing for Evaluation of Land Use Change Responses on Hydrology of Muga Watershed, Abbay River Basin, Ethiopia. J Earth Sci Clim Change 9: 493. doi: 10.4172/2157-7617.1000493

Determination of Crop Water Requirements for Maize in Abshege Woreda, Gurage Zone, Ethiopia

Abstract: In Ethiopia where crop production overly depends on rainfall and temperature, studying the variability of these climate variables at a local scale is essential to devise proper strategies that enhance adaptive capacity. In light of this, a study was conducted in Abshege Woreda, Gurage Zone to determine crop water requirement of maize, which is major food crop of the area. Ten years i.e., (2006-2015) Indibir station climatological records of (sunshine duration hr/day), maximum and minimum temperature (OC), humidity (%) and wind speed (km/day) at 2 meters height were used in FAO Penman Monteith method. Secondary data were used to collect important soil parameters required for determination of crop water requirement in the study area such as field capacity (FC), permanent wilting point (PWP), initial soil moisture depletion (as % TAM) and available water holding capacity (mm/meter) while data for maximum rain infiltration rates (mm/day) and maximum rooting depth (cm) were obtained from literature based on similar textural class of the soil in the study area. Lengths of total growing periods of the crop was determined from ten years climate data and planting date was 10th May acquired from OAWBA and farmers of the area. Crop coefficients (kc), rooting depth, depletion level and other agronomic parameters were obtained from FAO guidelines (No 56) for each growth stage. The analyzed data indicated that Crop water requirement was estimated using CROPWAT 8.0 for window. A maize variety with a growing period of 140 days to maturity would requires 423 mm depth of water, while 101 mm would be required as supplementary irrigation depth.

Coastal Erosion and Shoreline Change in Ganjam Coast along East Coast of India

Abstract: One of the rapidly changing coastal landforms is shoreline. It is very necessary to understand exact detection and frequent monitoring of shorelines through coastal processes and changing aspects of various coastal features. The present study is emphasized at investigating the shoreline changes along the Ganjam Coast, South Coast of Odisha by using geospatial techniques. The survey of India topographic maps and Landsat images were primarily used to extract shoreline features using software’s like Erdas Imagine and Arc GIS. The present study area is the Ganjam coast which is located on the south coast of Odisha which is from Prayagi to Bahuda river mouth. The beach has been eroded particularly in the Ramayapatam and Podampeta coastal tract due to various coastal processes that has taken place; such variations in the coastal processes are recorded by Landsat images and true colour image (Google earth) and also by repetitive field survey at different coastal sectors. The nature and magnitude of erosion indicates the immediate effect of waves attacking the coast under the impact of the low-pressure systems over the sea and the long-term impact of the loss of equilibrium between the waves and the coastline under the impact of the regimes of changing climate and sea level rise.

The Dynamics of the Coastal Land Scapes Over the Last Decades: Wind Drivers for Change Along the North Western Mauritanian Coast

Abstract: The alterations of the coastline are a major concern for maritime countries. Mauritania is no exception. As one of the countries with the highest marine productivity in the world, it stimulates growth in infrastructure development and jobs with its marine resources exploitation. But, the marine erosion and submersion have never been more critical to the entire coast. Coastal developments are planned, despite these risks both in the north and in the south. What about the coastline dynamic over the last decades and are they the same all along the Mauritanian coastline? What are the consequences on the coastal landscapes? The chronology of the paleo shoreline has been extensively studied near the Arguin Gulf for a better understanding of the infill of this large sedimentary basin and the last marine invasion started during the Nouakchottian period. The current retrospective study gives details on recent dynamics over the last seven decades. It is based on remote sensing images coupled with statistical analyses of climate data. A focus has been chosen on the Arguin Bank Park, which has been protected since 1976, because such wild areas represent a preferred window to evaluate natural responses. It is also home to coastal ecosystems of primary interest such as eelgrass beds. Five patterns differ in the dynamics of coastal segments that are a continuing accretion, a stability or an erosion. In addition, the time scales of these analyses allow for the identification of the impulse response of the environment, in phase or lagged time. Two new lagoons are developing and one of which shows a colonization by an eelgrass meadow system. The flooding of several insular wetland has become increasingly frequent and raises various questions about the mangroves and changes in the attractiveness of birdlife, the park's main richness. The various coastal dynamics may be the consequence of the sedimentary balance driven by northeasterly winds and the coastal drift currents. While the future projection of this coastal area remains complex, a better understanding of the dynamics should help feed the Strategy for managing the Mauritania’s coastline as well as the management of the Park. The ecological approach of the climate impacts opens up new perspective based on equivalent ecological concept.

Temporal Variabilities of the Climate along the Mauritanian Coast over the Last Decades

Abstract: Climate conditions affect all socio-economic spheres due to changes in the natural environment either in a geomorphological aspect or natural resources and biodiversity. The Sahelo-Saharan region has been subject to a very large number of climate studies after the main hazard of the 20th century that is called the “Great Drought” . Studies that focused on Mauritania and more specifically on its marine and coastal area, are very few whereas the government policies on this coastal area have been on the increase. The challenges of development are crucial such as the sustainability of the fishing sector, natural resources and infrastructure, for example the projects of two new on-going harbor. Another issue is the biodiversity world heritage that is present in this coastal area and perhaps in future, will be the tourism sector. Flood prevention for Nouakchott city which also represents a national challenge that has been subject to studies. Several climate parameters have been studied with an ecological approach. The aim was to identify the different temporalities of variation of climate in the perspective to compare with environmental changes. The study parameters have been selected with regard to their link with marine or coastal processes. The data used are from the synoptic weather stations of Nouadhibou and Nouakchott managed by the National Meteorological Office, ONM. The study period covers the four to seven last decades according the availability of data series. This period allows one to characterize the current situation and then, discuss the future at short to medium termes when regarding the projections from the Inter-governmental Permanent expert group for Climate Change and the national results reshaped by the ONM. This multi-decadal time scale corresponds to the one giving for strategy of development. The periodic and cyclic temporalities of variation have been revealed dominant. The air temperature is the only parameter which shows a long-term trend. The current deficit in easterly-wind appears to be the cause of the drastic increase in the vulnerability of the coast and islands to natural hazards. Such a situation has already occurred in the 1970s but the concerns about consequences have totally changed with development patterns and the advances in scientific knowledge. The seasonal to multi-decadal time scales of the study bring new insights on the current situation. The results also clarify certain on-going changes in environment.

Enhancing the Spatial Variability of Soil Salinity Indicators by Remote Sensing Indices and Geo-Statistical Approach

Abstract: Soil salinization is considered limiting factor for crop production and land management for dry land in Sudan, its spatial variation is affected by different factors of soil properties, vegetation and environment hence its interaction formulate the planning for successful sustainable agriculture in salt affected soils. This study aims to evolve the spatial prediction of soil salinity indicators by integrated remote sensing indices and geo-statistical cokriging model. Soil samples were collected from 476 square kilometer area in salt affected area, the samples were analyzed following standard procedures for electrical conductivity, sodium adsorption ratio, hydrogen ions and saturation percentage. Information of vegetation status identified by Normalized Difference Vegetation Index (NDVI) and soil salinization by Salinity index and brightness index were used and utilized for prediction of the soil parameters variability by cokriging model. It was found that the method was resulted in high accuracy based on RMSE and enhances the soil spatial variability assessment and provides significant interaction of different variables and indices in the landscape.

Comparative Assessment of Limnochemistry of Dal Lake in Kashmir

Abstract: A comparative assessment of different water quality parameters of Dal Lake, Kashmir was carried out during 2005 and 2015 in order to assess the changes that have occurred over time. The data was collected from five stations of the Lake during both the years. The results obtained indicate that the water quality of Dal Lake has significantly deteriorated. The different water quality parameters such as dissolved oxygen, chloride, NH4 -N, NO3 -N and total phosphorus showed marked variation from 2005 to 2015 with One Sample t-test showing significant differences (p=0.000) over this period. The NSFWQI ranges from 25-50 for both the years indicating the high pollution level and bad water quality of the Lake. The results of the present comparative investigation reflected increasing nutrient load in the Dal Lake which needs to be monitored for the conservation of Lake ecology.

Geophysical Investigation for Groundwater Potetial around Ladoke Akintola University of Technology Campus, Ogbomoso, Southwestern Nigeria

Abstract: Acute shortage of potable water on Ladoke Akintola University of Technology, Ogbomoso, Southwestern Nigeria has become a perennial problem over the years. In view of this, groundwater potential of the campus was investigated using geophysical methods. Ground Magnetic data were acquired at 10 m interval across the road network on the campus using the Proton Precession Magnetometer. Residualization process was carried out on the data using the Oasis Montaj 6.4.2 Software Package. Qualitative interpretation of the residual magnetic intensity map generated was used to categorize the campus into different geomagnetic anomaly zones. Seventy (70) Vertical Electrical Sounding (VES) data were also acquired and quantitatively interpreted. Geoelectric sections and isoresistivity of the weathered basement map of the campus were generated. Three (3) distinct geomagnetic zones which included basement high/ laterite (111 nT to 256 nT), intermediate magnetic intensity (-12 nT to 38 nT) and possibly basement depressions/ weathered basement (-279 nT to -89 nT) were delineated. The geoelectric sections revealed topsoil, laterite, weathered layer (aquifer) and the fresh basement respectively. The resistivities and thicknesses values of the layers were 170 Ωm to 2586 Ωm; 206 Ωm to 417 Ωm; 30 Ωm to 367 Ωm and 365 Ωm to ∞ and 0.3 m to 2.1 m; 3.0 m to 4.5 m and depth to rockhead of 0.3 m to 23.2 m. The groundwater potential of the campus was generally low due to high clay content of the aquifer. Citation: Bayowa OG, Fashola DK, Adegoke AB, Agesin AA, Oyeniyi SA (2018) Geophysical Investigation for Groundwater Potential around Ladoke Akintola University of Technology Campus, Ogbomoso, Southwestern Nigeria. J Earth Sci Clim Change 9: 485. doi: 10.4172/21577617.1000485

Long-Memory and Fractal Traces in KHz-MHz Electromagnetic Time Series Prior to the ML=6.1, 12/6/2007 Lesvos, Greece Earthquake: Investigation through DFA and Time-Evolving Spectral Fractals

Abstract: This paper presents evidence of long-lasting and chaotic trends in one-month kHz-MHz electromagnetic disturbances collected prior to a ML=6.1 shallow earthquake (June 12, 2017, 12:28:38 GMT, 38.84° N/26.36° E, 12 km deep, 37.5 km SSE of Mytilene town, Lesvos island, Greece) recorded by a telemetric ground station (39.23° N/26.27° E) located only 44 km away from the earthquake's epicenter. All analyzed earthquake occurrences (4.0 ≤ ML< 6.1) formed tight groups in both time and space which is significant for the investigation. The analysis is implemented via detailed timeevolving sliding-window two-slope DFA and power-law analysis of 4096 samples per window allowing hidden, potentially precursory, pre-earthquake trends to emerge. The classical two-exponent DFA results support the aspect of possible pre-earthquake activity 10-12 days prior to the ML=6.1 earthquake, for the 3-10 kHz antennas (both EW-NS orientations) and the 41-46 MHz ones, by simultaneously presenting a sudden increase of a parameter calculated from the two DFA exponent data. The time evolution of the power-law fractal-analysis data indicates activity 12-13 prior to the event, however, only for the 3 kHz antennas. Hurst exponents calculated in various analysis segments indicate persistency during the main pre-earthquake activity as well as persistency-anti-persistency changes. Potential pre-seismic activity prior to two other earthquakes of ML=5.0 and ML=4.6 is investigated and discussed. The precursory activity of reported time-series is discussed.

Effects on Surface Area, Intake Capacity and Regeneration of Impregnated Palm-Shell Activated Carbon with Monoethanolamide and 2-Amino-2-Methyl- 1-Propanol Equipped For CO2 Adsorption

Abstract: Granular palm shell activated carbon (AC) was impregnated separately with monoethanolamine (MEA) and 2-amino- 2-methyl-1-propanol (AMP) to improve its natural capacity and selectivity for carbon dioxide (CO2) adsorption. The total surface area, micropore volume, as well as the heterogeneity of the impregnated AC particles was considerably reduced due to impregnation. CO2 intake of impregnated 500 μm AC particles improved significantly and adsorptive capacity of 500 μm MEA-impregnated AC particles improved by 172% and 44% comparing to non-impregnated and AMP-impregnated AC particles respectively. Solid state amine stoichiometric results indicated that adsorption capacity of unhindered amine (MEA) is higher than that of hindered amine (AMP) by 50% contrary to liquid amines standard stoichiometry. Exhausted AMP-impregnated beds were regenerated by sweeping at room temperature with stream of pure nitrogen (N2) flowing at 60 ml/min for 4 hours. Heating up to 75°C was required to regenerate exhausted MEAimpregnated beds. Increasing feed gas flow rate has adverse effect on breakthrough time more than increasing bed operating temperature. Breakthrough time was utilized to evaluate the performance of the different adsorption beds.

Assessing the Impact of Climate Variability on Food Security in Kenya: A Case Study of Kisii County

Abstract: Climate variability and change has been found to be one of the factors that affect economies leading to food insecurity in various parts of the world Kenya is no exception This study looks at how climate variability has contributed to food insecurity in Kisii County, Kenya The objectives of this study is therefore to, (i) to examine the rainfall and temperature trends in Kisii County for a period of 30 years, (ii) to examine the effect of climate variability on food production and (iii) to assess the perception of local farmers on weather and climate information, (iv) to evaluate the coping strategies adopted at household level to bridge the gap on food deficit and (v) to assess the nutritional status of children and the elderly in Kisii County The data used was mainly rainfall and temperature data from meteorological stations and sample data gathered from selected groups The study population comprised of children between 6 months and 59 months, household heads, elderly people and agricultural officers Purposive sampling was used to select agricultural officers while multistage sampling was used to select respondents at household level Primary data was collected by use of a pre-tested questionnaire The Measurement of Upper Arm Circumference (MUAC) tape was used to collect nutritional status of children while Body Mass Index (BMI) data was obtained from elderly people Mann Kendall statistic was used to determine whether the trend of rainfall and temperature observed is significant while Chisquare test was used to determine whether the coping strategies observed varied significantly at household level From the analysis, rainfall has not shown any significant change in Kisii County while temperature trend has been significantly increasing over the years at 95% confidence level This could explain the observed reduction in river levels Analysis of crop production and price trends of major food crops in Kisii County showed a decreasing trend of food production leading to increase in price over the years This meant that farmers could not produce enough to take them to the next harvesting season, making farmers to adopt different coping strategies at household level which differed significantly according to Chi-Square test Malnutrition status of both elderly people above 59 years and children between 6-59 months were similar with 23% of both children/elderly being severely malnourished This study has only looked at climatic factors such as rainfall and temperature Other aspects such as depth of underground water, pH level of soil and the effects of land fragmentation also need to be looked at This study is important to both farmers in choosing the right crop to plant, and policy makers and planners in formulating the best mitigation and intervention strategies for Kisii County food insecurity problem This will further contribute to national efforts towards achievement of vision 2030

Metal Enrichment and Contamination in River and Estuary Sediments of Tamirabarani, South India

Abstract: The heavy metals enrichment and contamination are deliberated from twenty-four sediment samples collected along the Tamirabarani river and estuary. The concentration and spatial distribution of heavy metals in Tamirabarani River and estuary are analyzed for Copper, Nickel, Chromium, Lead, Zinc, Cadmium and Iron. The extent of pollution in these sediments was assessed using enrichment factor (EF), contamination factor (CF), geo-accumulation index (Igeo), Pollution Load Index (PLI). The contamination factor specify low to moderately contaminated, except for Cd. Igeo factors of all samples comprise strongly to extremely polluted index for Cd and moderately polluted index for Pb. The area PLI load for winter indicate higher variation than in summer, it is also noted that Pb and Cd are the major pollutants contributing high PLI values in the study area. This elevated value is mainly owing to the salinity intrusion and anthropogenic inputs. The constant variation of metals in sediment samples is due to the linking of industrial and anthropogenic influences. The combined and collective consequences go in front to a severe risk to the entire estuarine environment. Citation: Mukesh MV, Chandrasekaran A, Premkumar R, Keerthi BN (2018) Metal Enrichment and Contamination in River and Estuary Sediments of Tamirabarani, South India. J Earth Sci Clim Change 9: 497. doi: 10.4172/2157-7617.1000497

Comparison of MLP-ANN Scheme and SDSM as Tools for Providing Downscaled Precipitation for Impact Studies at Daily Time Scale

Abstract: Statistical downscaling has become an important part in most of the watershed scale climate change investigations. It is usually performed using multiple regression-based models. Basic working principle of such models is to develop a suitable relationship between the large scale (predictors) and the local climatic parameters called predictands. The development of such relationships using linear regression becomes very challenging when the local parameter to be downscaled is complex in nature such as precipitation. For this reason, use of nonlinear data driven techniques including Artificial Neural Networks (ANNs) is becoming more and more popular. Therefore, an attempt has been made in the study presented here to introduce a new Multi-Layer Perceptron (MLP) ANN-based scheme to develop a robust predictors-predictand relationship to be used as a downscaling model at daily time scale. The efficiency of this model has been compared with a popularly used model called Statistical Down Scaling Model (SDSM), for daily precipitation at the Clutha watershed in New Zealand. The results show that the model developed based on ANN scheme exhibits better performance than the SDSM. Hence, it is concluded that the use of artificial intelligence techniques such as ANN can greatly help in developing more efficient predictor-predictand models for even for precipitation being the toughest climate variable to model

Earthquake Risks in Bangladesh and Evaluation of Awareness among the University Students

Abstract: Earthquake is one of the major threats for Bangladesh for decades. In this study, we have tried to investigate the level of awareness about the earthquake among the university students in Bangladesh. Firstly, we have briefly discussed the risks of earthquake in Bangladesh, talked about the historic earthquakes and recently found threat or research. After that, we have analyzed our data collected from the survey we have conducted. We have got some positive results as well as a few horrifying scenarios. Encouraging results have found when we have asked some important matters that everyone should know about earthquake. But knowledge about the safety in the construction of the buildings and following the rules is quite opposite to that. Suggestions are offered in some definite sectors where improvement is required, and the government should push themselves harder in those sectors. of a large amount of sedimentary pile within the Bogra graben [5]. Tripura is one of the states of India surrounded by Bangladesh and two other states Mizoram and Assam of India surrounded by Koplili fault; Kaladan fault etc. which have produced many earthquakes. The Tripura-Naga organic belt is a zone of highly faulted tertiary deposits which has witnessed earthquakes of moderate magnitudes [2]. Shillong plateau is a geologically complex and seismically active region located on the collision boundary between Indian and Eurasian plate in the Meghalaya state of India. Its average altitude is about 1,500 m. The 1897 Ms. 8.0 Great Assam earthquake is well-known as a historic earthquake that occurred below the Shillong Plateau. The Shillong plateau presently behaves like a rigid body tied to the Indian Shield at a velocity of 46.5 ± 1 mm/a toward N 51o E [2,5]. Dauki fault zone is a 300 km long north dipping reverse fault along the Meghalaya-Bangladesh border and inferred to go through the southern margin of Shillong plateau and has a major role in deforming the surrounding areas. It is believed to be active in the past and it is most likely the fault associated with the magnitude >7 earthquake in Sylhet (Shilchar) historically known as Cachar earthquake (10 January 1869). Though it is inactive in the recent times still it is considered as one of the major threats for Bangladesh for the occurrence of devastating earthquakes [6]. A recent study reveals the existence of subduction zone of about 250 kilometers that can produce an earthquake of magnitude 8.2-9.0. After setting two dozen ground-positioning (GPS) instruments linked to satellites, capable of tracking tiny ground motions and analyzing the ten years of data the scientists have shown that eastern Bangladesh and a bit of eastern India are pushing diagonally into western Myanmar at a rapid clip46 millimeter per year or about 1.8 inches. After combining Citation: Md. Zaman AA, Sifty S, Rakhine NJ, Md. Abdul A, Amin R, et al. (2018) Earthquake Risks in Bangladesh and Evaluation of Awareness among the University Students. J Earth Sci Clim Change 9: 482. doi: 10.4172/2157-7617.1000482

Study on Groundwater Quality around Saroornagar Mandal in Hyderabad, Telangana

Abstract: Indian subcontinent has blessed with abundant water resources in the form perennial rivers and subsurface water. Every citizen of this country has the responsibility and duty towards protecting these most precious resources. Yet there is a scenario in India that thousands of people from different region are deprived of this due to over exploitation, poor management system. In this line, we have selected Saroor Nagar Mandal in Hyderabad City of Telangana state for conducting a model study on assessing groundwater quality. The study has been carried out in 6 locations of Saroornagar Mandal during pre-monsoon and post monsoon seasons by collecting 12 nos of bore water samples. Nine parameters were chosen for the analysis such as Temperature, pH, EC, Total dissolved solids, Total hardness, Calcium hardness, Turbidity, Chlorides and Bicarbonates. Finally, results of the analysis were compared with water quality standards such as BIS 10500 (1991) and CPHEEO manual of water sample and treatment. From this study, it was observed that calcium content was higher in few locations while other parameters were within the permissible limits. Citation: Arulneyam D, Premsudha R (2018) Study on Groundwater Quality around Saroornagar Mandal in Hyderabad, Telangana. J Earth Sci Clim Change 9: 483. doi: 10.4172/2157-7617.1000483

New Insights in Seagrass Mortality Patches at the Arguin Bank in the Perspectives of Climate Change

Abstract: All over the world, seagrass beds are key natural habitats for their ecosystem services. Those in the Gulf of Arguin, in Mauritania, have been monitored for more than twenty years; their conservation status is considered good despite very variable climatic conditions. In the absence of anthropogenic stress, the abiotic conditions have given rise to a number of hypotheses explaining temporary patches of mortality. These observations and hypotheses were revisited during the analysis of the evolution over 20 years of the total vegetation cover in Arguin Bay, evaluated by the NDVI index. This change over the medium term is consistent with wind conditions, drivers of sediment transport and hydrodynamics. The chronological contextualization of field observations by climatic conditions provides a new understanding of short-term variations. The importance of ongoing monitoring of this ecosystem is demonstrated; additional guidance is suggested to assess the specific resilience of each of the species that make up this seagrass beds.

Seismic Liquefaction Potential in Muscat, Sultanate of Oman

Abstract: Seismic liquefaction is a serious geotechnical engineering problem that takes place in saturated cohesion less soils during earthquakes due to the increase of pore-pressure so that the soil shear strength is decreased to zero. Muscat is situated in the north-eastern part of Oman close to Oman Mountains, which witnessed four earthquakes of order of 5.2 magnitude in the last 1300 years. The surface geology of Muscat reveals great variety of hard rocks in the eastern, southern and western parts to dense and lose sediments in the middle and northern parts. Muscat Municipality provided 1082 borehole data to be examined for their liquefaction susceptibility based on the soil characteristics. Susceptible soils only are further considered to liquefaction hazard assessment. Liquefaction occurs during an earthquake if the cyclic stress ratio (CSR) caused by the earthquake is higher than the cyclic resistance ratio (CRR) of the soil. CSR values were evaluated using probabilistic peak ground acceleration (PGA) values for return period of 2475 years at the surface given by detailed hazard and micro zonation studies. CRR for Muscat region is conducted based on the borehole data with N values of SPT tests, and shear wave velocity results from 99 MASW surveys over the entire region. All the required corrections to get standardized (N1) 60 values, to correct shear-wave velocity, and scale the results for Mw 6.0 instead of the proposed 7.5 are conducted. Liquefaction hazard maps were created using the minimum factor of safety (FS) at each site as a representative of the FS against liquefaction at that location. Results indicate that under the current level of seismic hazard, liquefaction potential is possible at some sites along the northern coast, where alluvial soils, shallow ground water table, and relatively high ground motion are present. The expected settlement of the soft soil at each liquefiable site is also evaluated.

Indigenous Knowledge Adaption Strategies in Response to Climate Change: The Case of North Gondar, Ethiopia

Abstract: The study was conducted in North Gonder Zone to identify the climate change variables and farmer’s indigenous climate change adaption strategies. The study took a sample of 130 farmers by using appropriate sampling techniques. Quantitative and qualitative data were collected from primary and secondary sources. Descriptive analysis was used to analyze farmer’s indigenous climate change adaption strategies quantitative. Besides, qualitative data were analyzed through narration. Different climate change variables, which affect livelihood of farmers, and variety of indigenous adaption strategies to minimize hazard due to climate change were identified. People living in the zone use indigenous adaption strategies based on Agro-ecology and farming system. The finding of research indicates that farmers adapt different strategies in response to different climatic change variables, and there are no best practices that can be used to tackle all climate change variables. Hence using a blend of the indigenous and scientific adaption strategies across the appropriate contexts is, therefore, of paramount importance.

Disastrous Events on Kelash-Mansarowar Route, Dharchula Tehsil in Pithoragarh District, Uttarakhand in India

Abstract: This paper presents evidence of trends of fractal properties and long memory in three-month variations of radon in soil, in Lesvos Island, Greece. The methodology employed consists of sliding-window (a) detrended fluctuation analysis, (b) fractal analysis, (c) rescaled range analysis and (d) fractal dimension analysis with the methods of Higuchi, Katz and Sevcik. During measurements two mild earthquakes occurred in the vicinity. The results of the detrended fluctuation analysis revealed four peaks with slopes between 1.2 and 1.5. The fractal analysis method resulted in three peaks with persistent power-law exponent values in the range 2.2 and 3.0. The rescaled-range analysis indicated persistent Hurst exponents between 0.7-0.9 and in some segments, between 0.9-1. The fractal dimension analysis showed four peaks with fractal dimensions in the range 1.3-2.0 (Higuchi and Katz methods) and 1.0-1.5 (Sevcik method). The results were compared in terms of conversion to Hurst exponents. Several persistent segments were addressed, along with persistency-anti-persistency switching instances. Potential geological sources are discussed and analyzed.