Jahangeer Porhemmat - Academia.edu (original) (raw)

Papers by Jahangeer Porhemmat

Open Journal of geology, 2018

Water science and engineering, Mar 1, 2016

Russian Meteorology and Hydrology, Mar 1, 2017

Cli ma to log i cal Re search In sti tute, Na tional Cen ter of Cli ma tol ogy, Pajoohes blvd., T... more Cli ma to log i cal Re search In sti tute, Na tional Cen ter of Cli ma tol ogy, Pajoohes blvd., Tehran, Iran e Ag ri cul tural Re search, Ed u ca tion and Ex ten sion Or ga ni za tion, Ag ri cul tural Gar den str.

Ain Shams Engineering Journal, Dec 1, 2020

Abstract The study aimed to evaluate the uncertainty indices in reservoir performance of Namrood-... more Abstract The study aimed to evaluate the uncertainty indices in reservoir performance of Namrood-Dam(Iran) that affected by climate change. To this end, downscaling was performed for the future period using the output of the EC-EARTH-GCM under the RCP scenarios and employing the LARS-WG6 model. The uncertainty in reservoir performance of under the current and climate change conditions, and 85% and 70% of the agricultural demand was evaluated using the WEAP. Based on the results, the reduction of inflow by 8.36% and 12.64% under RCP4.5 and RCP8.5, respectively, resulted in decreasing of the performance indices. In addition, 30% reducing the agricultural demand under the RCP4.5 had the highest values of sustainability index (SI) and its range for Firouz Kouh and Garmsar agriculture decreased by 20.64% and 34.2%, respectively. The ranges of SI variation were lower in comparison with the other indices, and accordingly, it enjoyed higher reliability for evaluating the system state.

Civil engineering infrastructures journal, Jun 1, 2019

This paper evaluated an integrated water resources management approach through linked WEAP-MODFLO... more This paper evaluated an integrated water resources management approach through linked WEAP-MODFLOW model. Study area is Ravasnar-Sanjabi plain located in Kermanshah province in the west of Iran. A MODFLOW model was evaluated and then, accepted as a groundwater model for the region in present research. Schematic WEAP model was provided as representing general features of water resources system after designing a conceptual model for the study area. The simplified rainfall-runoff model in WEAP was used to perform hydrological simulations. In the second step of present research, the groundwater model was linked to WEAP dynamically. Simulation years with 12 time steps per year included years of 2007-2015 for creating and verifying WEAP-MODFLOW model and years of 2015-2030 for performing scenarios. Statistical criteria included mean absolute error (MAE), root mean square error (RMSE), and Nash-Sutcliffe (NASH), with Box plot diagram being selected to assess accuracy of calibrated model. Four scenarios were implemented for 2015 until 2030. They included unchanged present situation and situations with 35%, 45% and 57% reduction of groundwater and surface water withdrawal. Results showed that the fourth scenario with a 57% decrease in the extraction of surface water and groundwater resources was the best one. Based on this scenario, exploitation of the system will be sustainable, with the system recovering as 0.023 meter rising per year. Finally, the results of present study indicated that the approach was feasible for planning and managing water resources in spite of the lack of some data.

Environmental Earth Sciences, Feb 1, 2018

Soil aquifer treatment (SAT) is an effective indirect technique for wastewater reuse. The present... more Soil aquifer treatment (SAT) is an effective indirect technique for wastewater reuse. The present study aims at assessing the soil capacity in arid region of Varamin on natural attenuation of inorganic constituents of municipal treated wastewater of Tehran City. In order to simulate SAT pond, four columns of 30 cm in height and 4 cm in diameter were filled with sandy loam soil taken from artificial recharge pond in Varamin plain. These columns were recharged by secondary treated wastewater from Shahre-Rey treatment plant under the plan of 12-h wetting and drying cycles. During the experiment, 50 pore volume passed through each column. The pH, EC, TDS, SAL, SAR, major ions, nitrate, phosphate and trace elements were measured in influent and effluent samples. The concentration of Na + , Ca 2+ , Mg 2+ , Cl − and SO 4 2− increased in effluent samples due to a washout process and dissolution of minerals. The soil could only attenuate NO 3 − , K + , Rb and PO 4 3− with the percentage of 18.4, 24.6, 67.7 and 83.6, respectively. The soil of studied area is rich in Cr, Ni, Sr, Pb, Cu, Zn, Ba and Rb. The concentrations of all mentioned trace elements, with the exception of Rb, have increased in the effluent samples with respect to influent. Also, the quality indices of TDS, SAL and SAR have increased 10.6, 25.2 and 8.7%, respectively, in effluent. Soil column samples, at the end of experiment, contain high amounts of major and trace elements. Consequently, there is a potential risk for groundwater contamination in long-term recharge.

Iranian Journal of Watershed Management Science and Engineering, Oct 15, 2016

Research Journal of Environmental Sciences, Mar 1, 2009

فصلنامه علمی-پژوهشی علوم زمین, Feb 20, 2018

Garesoo river basin in Doab-Merek, as studying area of this research, located in northwest of Ker... more Garesoo river basin in Doab-Merek, as studying area of this research, located in northwest of Kermanshah province in west part of Iran. There is long-term hydro climatologic data in this basin about rainfall, temperature, etc. (more than 50 years) and main river data (about 35 years). Due to intense fall down groundwater level and seasonal river drying, in the past 10 years .It was necessary that studies be done to the management water resources of region. Studies performed at first by linking MODFLOW to WEAP model with information and initial understanding of the geology and the others information of the area. The results were not satisfactory especially regarding the prediction runoff basin in outlet, despite the long term data. After these initial studies, and based on complete studying, it was cleared that complicated geological conditions with new Tectonics activities were key to the adaptation of the model to reality. In addition, geophysical surveys using radar approach showed that the fault is in match with the trend of river, and it can creat hydrolic interaction between Karstic and fractured bed rock and porous medium and also river in outlet. Finally we achieved a good acceptance matching between calculated and observed discharge of river in Doab-Merek station with satisfactory results.

Arabian Journal of Geosciences

Journal of Agrometeorology, 2021

Intensity-duration-frequency (IDF) curves are among the standard design tools for many engineerin... more Intensity-duration-frequency (IDF) curves are among the standard design tools for many engineering applications such as urban drainage management. Since climate change may considerably affect precipitation, updating of IDF curves is highly necessary. The present study aims to examine the impacts of climate change on IDF curves of Shiraz synoptic station using downscaled outputs of Hadcm3 AOGCM under various emission scenarios (A1B, A2,B1) applying larswg-5 model for the period of 2046 to 2065. The fitted Gumbel distribution was used to estimate the maximum short-term precipitation quantiles in the base period (1968-2000) and the verified empirical Bell type equation was used for the future period. The results show that the mean of maximum daily precipitation and annual precipitation will decrease in the future. Also, the maximum precipitation intensities up to 60 min duration will reducefrom 0.15 mm hr-1 to about 10.79 mm hr-1 compared to the observed period in all returns periods a...

Iranian Journal of Watershed Management Science and Engineering, 2010

Applied Ecology and Environmental Research, 2017

In this paper the daily runoff of Ravansar Sanjabi basin, Kermanshah, Iran is simulated through S... more In this paper the daily runoff of Ravansar Sanjabi basin, Kermanshah, Iran is simulated through SRM and SWAT models. SRM is a deterministic and degree-day based model which simulates or forecasts the daily runoff in mountain basins through Snow Cover Area (SCA) variable and also other meteorological data such as rainfall and temperature. The images of Snow Covered Area obtained from MOD10A2 of the MODIS satellite are used to calculate the SCA as a key variable for SRM in this study. On the other hand, SWAT model is a continuous and distributive model which can simulate the hydrological processes in basins through a wide range of information such as physical information of basins (soil, land use, slope) as well as weather data such as precipitation, temperature, wind, relative humidity, solar radiation. Simulation results during the calibration and validation periods are evaluated through three statistical indices: Nash-Sutcliffe efficiency (NSE) coefficient, coefficient of determination, and volume difference. Comparison of simulated and observed flow hydrographs and calculated statistical coefficients show that SRM model results are acceptable in simulating daily runoff for both calibration and validation periods (NSE: 0.9 and 0.95 respectively); while SWAT model presents weak results (NSE: 0.14 and 0.16, respectively).