scholarly journals Validating Dynamically Downscaled Climate Projections for Mountainous Watersheds Using Historical Runoff Data Coupled with the Distributed Hydrologic Soil Vegetation Model (DHSVM)

Water ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1389
Author(s):  
Mohammad M. Hasan ◽  
Courtenay Strong ◽  
Adam K. Kochanski ◽  
Steven J. Burian ◽  
Michael E. Barber

The performance of dynamically downscaled climate fields with respect to observed historical stream runoff has been assessed at basin scale using a physically distributed hydrologic model (DHSVM). The dynamically downscaled climate fields were generated by running the Weather Research & Forecasting (WRF) model at 4-km horizontal resolution with boundary conditions derived from the Climate Forecast System Reanalysis. Six hydrologic models were developed using DHSVM for six mountainous tributary watersheds of the Jordan River basin at hourly time steps and 30-m spatial resolution. The size of the watersheds varies from 19 km2 to 130 km2. The models were calibrated for a 6-year period from water year (WY) 1999–2004, using the observed meteorological data from the nearby Snow Telemetry (SNOTEL) sites of the Natural Resources Conservation Services (NRCS). Calibration results showed a very good fit between simulated and observed streamflow with an average Nash-Sutcliffe Efficiency (NSE) greater than 0.77, and good to very good fits in terms of other statistical parameters like percent bias (PBIAS) and coefficient of determination (R2). A 9-year period (WY 2001–2009) was selected as the historical baseline, and stream discharges for this period were simulated using dynamically downscaled climate fields as input to the calibrated hydrologic models. Historical baseline results showed a satisfactory fit of simulated and observed streamflow with an average NSE greater than 0.45 and a coefficient of determination above 0.50. Using volumetric analysis, it has been found that the total volume of water simulated using downscaled climate projections for the entire historical baseline period for all six watersheds is 4% less than the observed amount representing a very good estimation in terms of percent error volume (PEV). However, in the case of individual watersheds, analysis of total annual water volumes showed that estimated total annual water volumes were higher than the observed for Big Cottonwood, City Creek, Millcreek and lower than the observed total annual volume of water for Little Cottonwood, Red Butte Creek, and Parleys Littledell, demonstrating similar characteristics obtained from the calibration results. Seasonal analysis showed that the models can capture the flow volume observed for Big Cottonwood, City Creek and Red Butte Creek during the peak season, and the models can capture the flow volume observed for all the watershed satisfactorily except Big Cottonwood during the dry season. Study results indicated that the dynamically downscaled climate projections used in this study performed satisfactorily in terms of stream runoff, total flow volume, and seasonal flow analyses based on different statistical tests, and can satisfactorily capture flow patterns and flow volume for most of the watersheds considering the uncertainties associated with the study.

2014 ◽  
Vol 15 (4) ◽  
pp. 1404-1418 ◽  
Author(s):  
Seshadri Rajagopal ◽  
Francina Dominguez ◽  
Hoshin V. Gupta ◽  
Peter A. Troch ◽  
Christopher L. Castro

Abstract Water managers across the United States face the need to make informed policy decisions regarding long-term impacts of climate change on water resources. To provide a scientifically informed basis for this, the evolution of important components of the basin-scale water balance through the end of the twenty-first century is estimated. Bias-corrected and spatially downscaled climate projections, from phase 3 of the Coupled Model Intercomparison Project (CMIP3) of the World Climate Research Programme, were used to drive a spatially distributed Variable Infiltration Capacity (VIC) model of hydrologic processes in the Salt–Verde basin in the southwestern United States. From the suite of CMIP3 models, the authors select a five-model subset, including three that best reproduce the historical climatology for the study region, plus two others to represent wetter and drier than model average conditions, so as to represent the range of GCM prediction uncertainty. For each GCM, data for three emission scenarios (A1B, A2, and B1) were used to drive the hydrologic model into the future. The projections of this model ensemble indicate a statistically significant 25% decrease in streamflow by the end of the twenty-first century. The primary cause for this change is due to projected decreases in winter precipitation accompanied by significant (temperature driven) reductions in storage of snow and increased winter evaporation. The results show that water management in central Arizona is highly likely to be impacted by changes in regional climate.


2021 ◽  
Vol 3 ◽  
Author(s):  
Daria B. Kluver ◽  
Wendy Robertson

Fundamental differences in the nature of climate and hydrologic models make coupling of future climate projections to models of watershed hydrology challenging. This study uses the NCAR Weather Research and Forecast model (WRF) to dynamically downscale climate simulations over the Saginaw Bay Watershed, MI and prepare the results for input into semi-distributed hydrologic models. One realization of the bias-corrected NCAR CESM1 model's RCP 8.5 climate scenario is dynamically downscaled at a spatial resolution of 3 km by 3 km for the end of the twenty-first century and validated based on a downscaled run for the end of the twentieth century in comparison to ASOS and NWS COOP stations. Bias-correction is conducted using Quantile Mapping to correct daily maximum and minimum temperature, precipitation, and relative humidity for use in future hydrologic model experiments. In the Saginaw Bay Watershed the end of the twenty-first century is projected to see maximum and minimum average daily temperatures warming by 5.7 and 6.3°C respectively. Precipitation characteristics over the watershed show an increase in mean annual precipitation (average of +14.3 mm over the watershed), mainly due to increases in precipitation intensity (average of +0.3 mm per precipitation day) despite a decrease in frequency of −10.7 days per year. The projected changes have substantial implications for watershed processes including flood prediction, erosion, mobilization of non-point source and legacy contaminants, and evapotranspirative demand, among others. We present these results in the context of usefulness of the downscaled and bias corrected data for semi-distributed hydrologic modeling.


2012 ◽  
Vol 43 (1-2) ◽  
pp. 156-166 ◽  
Author(s):  
Xiuqin Fang ◽  
Liliang Ren ◽  
Qiongfang Li ◽  
Xiaofan Liu ◽  
Fei Yuan ◽  
...  

An algorithm for estimating daily spatial actual evapotranspiration (ET) from remotely sensed MODIS data is presented. It is based on the surface energy balance scheme and the modified Priestley–Taylor equation, and has been applied to the MODIS data acquired during growing seasons over the Laohahe River basin, northeastern China. Spatial distributed mapping of daily ET for 22 clear sky days in the year of 2000 from MODIS images over the study area were obtained. In order to validate ET values estimated from MODIS data, regional daily ET values were calculated using the lumped modified Xinanjiang hydrologic model and distributed SWAT model based on the water balance scheme, respectively. The relationship between actual daily ET estimated from MODIS images and basin-scale ET calculated from the hydrologic model were in good agreement with acceptable correlation coefficient. The results suggested that the algorithm is applicable and operational for estimating and mapping basin-scale distributed daily actual ET over the study area. In order to use the algorithm proposed by this paper for water resource management and agricultural decision making, the algorithm should be validated using more data and be tested under different environment and different land use scenario conditions in future work.


2020 ◽  
Vol 8 (1) ◽  
pp. 87-97
Author(s):  
Nana Diana ◽  
Tati Apriani

This study aims to examine the influence of investment returns and Risk Based Capital (RBC) Tabarru Funds to the profit of sharia life insurance in Indonesia from 2014-2019. This study The type of this research is quantitative research with descriptive verification as a method. This research method uses descriptive verification method with quantitative approach. The data used in this study were sourced from the financial statements of Islamic life insurance companies in Indonesia for the 2014-2019 period. Then the data obtained were analyzed using multiple linear regression analysis and hypothesis testing consisting of t test and f test with the help of SPSS 21 software. The sampling technique uses non probability sampling with purposive sampling technique. Based on the results of the study it can be seen that the development of investment returns on Sharia Life Insurance in Indonesia has fluctuated and even suffered losses. While the development of Risk Based Capital (RBC) has increased and decreased but overall above 120% as determined by the government. Likewise, the profits earned in each year fluctuate. The results of statistical tests show that investment results partially have a positive effect on profit and Risk Based Capital (RBC) of Tabarru funds partially has a negative effect on profit. Simultaneously investment return and Risk Based Capital (RBC) affect on profit. In addition, the results of the coefficient of determination (R2) were obtained which obtained a value of 81%. This shows that the variable investment returns and Risk Based Capital (RBC) can affect earnings by 81% and the remaining 19% is influenced by other variables not used in this study.


2020 ◽  
Vol 4 (1) ◽  
Author(s):  
Masruri Muchtar ◽  
Prasetya Utama

ABSTRACT:The auditor should have eminence audit judgment to support their assignment This research aims to provide empirical evidence that self-efficacy, experience, level of education, and skepticism have an impact on audit judgment. The population are auditors who had carried out post-clearance audit assignments. This research uses a quantitative approach by testing the theories and hypotheses that have been prepared. Ordinary least square (OLS) linear regression as an analytical model is used in this study. Results show that experience and education level have no impact on audit judgment, whereas self-efficacy and skepticism have a positive and significant impact on audit judgment. Efforts to improve self-efficacy and auditor skepticism are urgently needed. The coefficient of determination describes the variation of variables of self-efficacy, experience, level of education, and skepticism able to explain the variation of audit judgment variables by 51%. The remaining 49% is explained by other variables not involved in this study. Future studies may enhance with other variables and employ in-depth interview methods.Keywords: audit judgment, experience, level of education, post-clearance audit, self-efficacy, skepticism, post-clearance audit ABSTRAK:Auditor seyogyanya memiliki kemampuan audit judgment yang berkualitas guna mendukung penugasannya. Tujuan penelitian adalah memberikan bukti empiris bahwa efikasi diri, pengalaman, tingkat pendidikan, dan skeptisisme memiliki pengaruh terhadap audit judgement. Populasi dalam penelitian ini adalah auditor Direktorat Jenderal Bea dan Cukai (DJBC) yang pernah melakukan post clearance audit. Ini merupakan pendekatan kuantitatif yang menguji teori serta hipotesis yang telah disusun. Riset ini menggunakan regresi linear ordinary least square (OLS) sebagai model analisis. Hasil studi memperlihatkan pengalaman dan tingkat pendidikan tidak berpengaruh pada audit judgement, namun efikasi diri dan skeptisisme berpengaruh signifikan pada audit judgement. Implikasinya DJBC perlu memberikan perhatian khusus terhadap berbagai upaya dalam peningkatan efikasi diri dan skeptisisme auditor. Tulisan ini adalah pengembangan beberapa penelitian sebelumnya namun dalam konteks pengujian untuk jenis audit ketaatan. Nilai koefisien determinasi menggambarkan variasi variabel efikasi diri, pengalaman, tingkat pendidikan, dan skeptisisme dapat menjelaskan variasi variabel audit judgement sebesar 51%. Sisanya sebesar 49% dijelaskan oleh variabel lainnya yang tidak diujikan dalam tulisan ini. Dengan adanya keterbatasan waktu pada penelitian ini diharapkan mendorong penelitian berikutnya untuk dapat menyertakan beberapa variabel lain yang relevan dan melengkapinya dengan metode in-depth interview.Kata Kunci: bea dan cukai, efikasi diri, pengalaman, skeptisisme, tingkat pendidikan


Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1769
Author(s):  
Maria Macarena Arrien ◽  
Maite M. Aldaya ◽  
Corina Iris Rodriguez

Agriculture is the largest fresh water consuming sector, and maize is the most produced and consumed crop worldwide. The water footprint (WF) methodology quantifies and evaluates the water volumes consumed and polluted by a given crop, as well as its impacts. In this work, we quantified for the first time the green WF (soil water from precipitation that is evapotranspired) and the green virtual water exports of maize from Buenos Aires province, Argentina, during 2016–2017, due to the relevance of this region in the world maize trade. Furthermore, at local level, we quantified the green, blue (evapotranspired irrigation), and grey (volume of water needed to assimilate a pollution load) WF of maize in a pilot basin. The green WF of maize in the province of Buenos Aires ranged between 170 and 730 m3/ton, with the highest values in the south following a pattern of yields. The contribution of this province in terms of green virtual water to the international maize trade reached 2213 hm3/year, allowing some water-scarce nations to ensure water and water-dependent food security and avoid further environmental impacts related to water. At the Napaleofú basin scale, the total WF of rainfed maize was 358 m3/ton (89% green and 11% grey) and 388 m3/ton (58% green, 25% blue, and 17% grey) for the irrigated crop, showing that there is not only a green WF behind the exported maize, but also a Nitrogen-related grey WF.


1996 ◽  
Vol 21 (3) ◽  
pp. 211-218 ◽  
Author(s):  
A. Limaye ◽  
Erik B. Kluzek ◽  
Gail E. Bingham ◽  
J.P. Riley

2020 ◽  
Vol 45 (2) ◽  
pp. 40-48
Author(s):  
A. J. Atansuyi ◽  
U. C. Ihendu ◽  
C. A. Chineke

This study was conducted to determine the growth performance, correlation and regression estimates of seven-chicken strains in South-western Nigeria using a total of 300 day-old chicks. The birds were divided into seven groups based on their strain. The seven strains are Normal feather (NF), Fulani ecotype (FE), Frizzle feather (FF), naked neck (NN) and Transylvania indigenous strains while Hubbard and Marshal were meat-type exotic chickens. There were forty- five (45) unsexed day-old chicks in each strain except the Frizzle feather that were 30 in number. Completely randomized design (CRD) was used for the trial that lasted for 8 weeks. The birds were fed experimental diets ad libitum throughout the period of the study. Results showed that there were significant differences (p<0.05) in the initial and final weights of the birds. It was observed that exotic strains weighed heavier (3569.73gHB) than their indigenous counterparts (1391.11gNF). However, the Fulani ecotype weighed heaviest (1840.99g) among Nigeria indigenous strains during the experimental period. This showed that FE strains are generally heavy breed chicken and could be incorporated into a meat producing indigenous chicken if improved upon. The result of the correlation coefficients showed that a very strong, positive and highly significant (P<0.001) relationship existed between body weights and linear body measurements as most of the values are (>0.40). All the body parameter examined had significant (p<0.01) and direct relationship with the body weight. Shoulder-to-tail length (STL) had the highest coefficient of 0.98.The high correlation estimates obtained in this study could be as a result of pleiotropy, heterozygosity or linkage of genes in the birds. The three functions were highly significant (p<0.05) for all the parameters studied. This shows that the functions well described the parameters. On the basis of coefficient of determination (R ), the body weight of poultry birds at any age can be predicted most accurately with BRG using cubic function.


2021 ◽  
Vol 8 (1) ◽  
pp. 013-018
Author(s):  
Pria Wahyu Romadhon Girianto ◽  
Mega Wahyu Mulyasari

Renal Disease was a chronic disease that the most attacking people in Indonesia. Damage to this vital organ in the human body greatly affected a person's health condition, one of which was anemia. This study aimed to determine the effectiveness of Durante hemodialysis PRC transfusions on hemoglobin levels. The method used was Pre-experimental design, with the One group pre-post test design approach. With a sample of 49 patients who underwent regular hemodialysis at RSUD dr. Iskak Tulungagung. Data were obtained by direct observation. Processed by computerized methods with a statistical t-test, the significance level (α) was 0.05. The study results showed that the hemoglobin levels of the pre-Durante hemodialysis PRC transfusion patients were 4-5 mg/dl (53.06%), and the hemoglobin levels of the post-Durante hemodialysis PRC transfusion patients were 6.1-7 mg/dl (34.69%). The results of statistical tests showed that there was an increase in hemoglobin levels in patients who received Durante hemodialysis PRC transfusion by 1.22 mg/dl because p-value = 0.000 < 0.05 (α) means that there was an effect. It could be concluded that the delivery of Durante hemodialysis PRC transfusion could help increase hemoglobin levels. This finding was very helpful for chronic Renal Disease patients undergoing hemodialysis, who have been using erythropoietin preparations because PRC transfusions were cheaper and more effective when compared to using erythropoietin preparations


2012 ◽  
Vol 16 (6) ◽  
pp. 1709-1723 ◽  
Author(s):  
D. González-Zeas ◽  
L. Garrote ◽  
A. Iglesias ◽  
A. Sordo-Ward

Abstract. An important step to assess water availability is to have monthly time series representative of the current situation. In this context, a simple methodology is presented for application in large-scale studies in regions where a properly calibrated hydrologic model is not available, using the output variables simulated by regional climate models (RCMs) of the European project PRUDENCE under current climate conditions (period 1961–1990). The methodology compares different interpolation methods and alternatives to generate annual times series that minimise the bias with respect to observed values. The objective is to identify the best alternative to obtain bias-corrected, monthly runoff time series from the output of RCM simulations. This study uses information from 338 basins in Spain that cover the entire mainland territory and whose observed values of natural runoff have been estimated by the distributed hydrological model SIMPA. Four interpolation methods for downscaling runoff to the basin scale from 10 RCMs are compared with emphasis on the ability of each method to reproduce the observed behaviour of this variable. The alternatives consider the use of the direct runoff of the RCMs and the mean annual runoff calculated using five functional forms of the aridity index, defined as the ratio between potential evapotranspiration and precipitation. In addition, the comparison with respect to the global runoff reference of the UNH/GRDC dataset is evaluated, as a contrast of the "best estimator" of current runoff on a large scale. Results show that the bias is minimised using the direct original interpolation method and the best alternative for bias correction of the monthly direct runoff time series of RCMs is the UNH/GRDC dataset, although the formula proposed by Schreiber (1904) also gives good results.


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