scholarly journals Drought indices and trend analysis

2020 ◽  
Vol 15 (1) ◽  
pp. 39-45
Author(s):  
Patrik Nagy ◽  
Martina Zeleňáková
Keyword(s):  
Drought Index ◽  
Extreme Rainfall ◽  
Kendall Test ◽  
Drought Indices ◽  
Test Results ◽  
Rainfall Trend ◽  
Reconnaissance Drought Index ◽  
Rdi Index ◽  
Dry Seasons ◽  
The Subject

Abstract In recent times, extremely dry seasons have been occurring more and more often in the eastern Slovakia, alternating with extremely wet seasons like torrential floods from extreme rainfall. Trend of reconnaissance drought index (RDI) and streamflow drought index (SDI) was evaluated in the paper using the Mann-Kendall test. The indices were evaluated at six climatic and river stations in the eastern Slovakia. The Mann-Kendal test results showed that the trend in the SDI index is not significant in 5 stations and only in one station the trend is significant. In the RDI index the trend is not significant in four stations and the trend is significant in two stationshe abstract is to indicate the subject of the paper, how the author proposes to develop the subject and its overall objective, aim or outcome.

scholarly journals Kecenderungan dan Perubahan Hujan Ekstrem Harian di Pulau Madura

2020 ◽  
Vol 18 (1) ◽  
pp. 89-96
Author(s):  
Ahmad Nur Akma Juangga Fura ◽  
Retno Utami Agung Wiyono ◽  
Indarto Indarto
Keyword(s):  
Flood Hazard ◽  
Parametric Method ◽  
Extreme Rainfall ◽  
Kendall Test ◽  
Random Processes ◽  
Rain Gauge ◽  
Rainfall Trend ◽  
Significance Level ◽  
High Level ◽  
Crossing Test

Madura subject to a high level of flood hazard. One of the main causes of flood is extreme rainfall. Global warming generates changes in the amount of extreme rainfall. This research is conducted to identify and to analyze the trends, changes, and randomness of 24-hour extreme rainfall data on Madura Island. The method used is a non-parametric method which includes the Median Crossing test, the Mann-Kendall test, and the Rank-Sum test at the significance level of α =0.05. The analysis was carried out on 31 rain gauge stations. The recording period observed is between 1991-2015. The results of the analysis show that based on the Median Crossing test, most rainfall stations have data originating from random processes. The result shows also that the maximum 24-hour extreme rainfall trend is significantly decreased in a few locations, while for the majority of other stations have no experience a significant trend.

scholarly journals A Non-Stationary and Probabilistic Approach for Drought Characterization Using Trivariate and Pairwise Copula Construction (PCC) Model

2021 ◽  
Author(s):  
Soumyashree Dixit ◽  
K V Jayakumar
Keyword(s):  
Drought Index ◽  
Southern Oscillation ◽  
Standardized Precipitation Index ◽  
Precipitation Index ◽  
Drought Indices ◽  
Climate Indices ◽  
Copula Model ◽  
Reconnaissance Drought Index ◽  
Drought Characteristics ◽  
Recurrence Intervals

Abstract Under the variable climatic conditions, the conventional Standardized Precipitation Index (SPI) and Reconnaissance Drought Index (RDI) are inadequate for predicting extreme drought characteristics. So in the present study, two indices namely, Non-stationary Standardized Precipitation Index (NSPI) and Non-stationary Reconnaissance Drought Index (NRDI) are developed by fitting non-stationary gamma (for precipitation series) and lognormal (for initial values,δ0) distributions. The Generalized Additive Model in Location, Scale and Shape (GAMLSS) framework, with time varying location parameters considering the external covariates, is used to fit the non-stationary distributions. This includes various large scale climate indices namely Multivariate ENSO Index (MEI), Southern Oscillation Index (SOI), Sea Surface Temperature (SST), and Indian Ocean Dipole (IOD) as external covariates for the non-stationary drought assessment. The performances of stationary and non-stationary models are compared based on the Akaika Information Criterion (AIC). Additionally, the drought characteristics are evaluated using Run theory analysis for both stationary and non-stationary drought indices. The study also concentrated on the trivariate copula as well as the Pairwise Copula Construction (PCC) models to estimate the drought recurrence intervals. The comparison of two copula models revealed that the PCC model performed better than the trivariate Student’s t copula model. The recurrence intervals arrived at for the drought events are different for trivariate copula model and PCC model. The area taken for the study is the Upper and Lower sub basins of the Godavari River basin. This study shows that non-stationary drought indices will be helpful in the accurate estimate of the drought characteristics under the changing climatic scenario.

scholarly journals Climate Variability Impact on the Spatiotemporal Characteristics of Drought and Aridityin Arid and Semi-Arid Regions

2019 ◽  
Vol 33 (15) ◽  
pp. 5015-5033 ◽  
Author(s):  
Ruqayah Mohammed ◽  
Miklas Scholz
Keyword(s):  
Climate Variability ◽  
Drought Index ◽  
Potential Evapotranspiration ◽  
Standardized Precipitation Index ◽  
Meteorological Drought ◽  
Drought Indices ◽  
Homogeneity Test ◽  
Climate Data ◽  
Reconnaissance Drought Index ◽  
Semi Arid

AbstractInvestigating the spatiotemporal distribution of climate data and their impact on the allocation of the regional aridity and meteorological drought, particularly in semi-arid and arid climate, it is critical to evaluate the climate variability effect and propose sufficient adaptation strategies. The coefficient of variation, precipitation concentration index and anomaly index were used to evaluate the climate variability, while the Mann-Kendall and Sen’s slope were applied for trend analysis, together with homogeneity tests. The aridity was evaluated using the alpha form of the reconnaissance drought index (Mohammed & Scholz, Water Resour Manag 31(1):531–538, 2017c), whereas drought episodes were predicted by applying three of the commonly used meteorological drought indices, which are the standardised reconnaissance drought index, standardized precipitation index and standardized precipitation evapotranspiration index. The Upper Zab River Basin (UZRB), which is located in the northern part of Iraq and covers a high range of climate variability, has been considered as an illustrative basin for arid and semi-arid climatic conditions. There were general increasing trends in average temperature and potential evapotranspiration and decreasing trends in precipitation from the upstream to the downstream of the UZRB. The long-term analysis of climate data indicates that the number of dry years has temporally risen and the basin has experienced succeeding years of drought, particularly after 1994/1995. There was a potential link between drought, aridity and climate variability. Pettitt’s, SNHT, Buishand’s and von Neumann’s homogeneity test results demonstrated that there is an evident alteration in the mean of the drought and aridity between the pre- and post-alteration point (1994).

IMPROVE THE INTERETATION OF STUDY SUBJECTS PANCASILA AND CITIZENSHIP EDUCATION BY APPLYING KONSTEXTUAL LEARNING MODEL BERBASIS A TASK IN CLASS INFORMATICS XI SMK BINA ECLECTUS ACADEMIC YEAR 2015/2016

EDUKASI ◽  
2016 ◽  
Vol 13 (2) ◽  
Author(s):  
Hasanudin S. Usman
Keyword(s):  
Teaching And Learning ◽  
Learning Model ◽  
Positive Influence ◽  
Motivation To Learn ◽  
Test Results ◽  
Applied Learning ◽  
Know How ◽  
Design Activities ◽  
The Subject ◽  
Academic Year

The purpose of this research is to know how to incerease the students’ learning achievement that has been applied learning contextual task-based learning model and to know the influence of contextual learning in  the task-based teaching model to improve achievemen and motivation to learn the material pe civis lesson.   This research is an action research by theree rounds. Each round consists of four phases. Design activities are observation, and revesion. The subject of the research is XI grade students of Bina Informatika Ternate accademic year 2015/2016. Data obtained in the form of a formative test results, observation sheet teaching and learning activities. The results of the research showed that students’ achivement increased from round I to III that the round 1, (70.00 % ), (92,50 %)  3 cycles, conclusions of this research is the method of cooperatif learning can be a positive influence on students motivation and achievement in material udaya politics in Indonesia. It means that this model can be used as one of the alternative learning for Pkn.            Kata  kunci: PKn, cooperative learning method

DEVELOPMENT OF STREAMFLOW DROUGHT INDICES IN THE MORAVA RIVER BASIN

2020 ◽  
Author(s):  
Ondrej Ledvinka ◽  
◽  
Pavel Coufal ◽  
Keyword(s):  
Time Series ◽  
Kendall Test ◽  
Drought Indices ◽  
Drought Period ◽  
Left Hand ◽  
Low Flows ◽  
Current Period ◽  
Catchment Size ◽  
Morava River ◽  
The Stability

The territory of Czechia currently suffers from a long-lasting drought period which has been a subject of many studies, including the hydrological ones. Previous works indicated that the basin of the Morava River, a left-hand tributary of the Danube, is very prone to the occurrence of dry spells. It also applies to the development of various hydrological time series that often show decreases in the amount of available water. The purpose of this contribution is to extend the results of studies performed earlier and, using the most updated daily time series of discharge, to look at the situation of the so-called streamflow drought within the basin. 46 water-gauging stations representing the rivers of diverse catchment size were selected where no or a very weak anthropogenic influences are expected and the stability and sensitivity of profiles allow for the proper measurement of low flows. The selected series had to cover the most current period 1981-2018 but they could be much longer, which was considered beneficial for the next determination of the development direction. Various series of drought indices were derived from the original discharge series. Specifically, 7-, 15- and 30-day low flows together with deficit volumes and their durations were tested for trends using the modifications of the Mann– Kendall test that account for short-term and long-term persistence. In order to better reflect the drivers of streamflow drought, the indices were considered for summer and winter seasons separately as well. The places with the situation critical to the future water resources management were highlighted where substantial changes in river regime occur probably due to climate factors. Finally, the current drought episode that started in 2014 was put into a wider context, making use of the information obtained by the analyses.

Methodology to Increase Flexibility in Inter-Region Flow Control for Urban Traffic

2021 ◽  
pp. 036119812199742
Author(s):  
Sunghoon Kim ◽  
Monica Menendez ◽  
Hwasoo Yeo
Keyword(s):  
Flow Control ◽  
Real Time ◽  
Urban Traffic ◽  
Test Results ◽  
Flow Restriction ◽  
Region Flow ◽  
The Subject ◽  
Negative Impacts ◽  
Transfer Flow ◽  
Supply Level

Perimeter control is used to regulate transfer flows between urban regions. The greedy control (GC) method takes either the minimum or the maximum for the control inputs. Although it has the advantage of simplicity for real-time feasibility, a few existing studies have shown that it can sometimes have negative impacts because of unnecessary transfer flow restrictions. To reduce unnecessary restrictions, this study provides a method that gives flexibility to ease the strict conditions of the conventional GC. First, we propose a modification as a way of granting exceptions to the flow restriction under specific conditions. Second, we develop an algorithm to determine the threshold dynamically for accepting the exception, by comparing the possible outflow loss of the subject region and the possible outflow gain of its neighboring regions. The test results show that this flexible greedy control can handle the balance between the transfer demands and the greed of regions for securing the supply level, while increasing the performance in both vehicle hours traveled and trip completion.

scholarly journals Evaluation of Drought Indices Based on Thermal Remote Sensing of Evapotranspiration over the Continental United States

2011 ◽  
Vol 24 (8) ◽  
pp. 2025-2044 ◽  
Author(s):  
Martha C. Anderson ◽  
Christopher Hain ◽  
Brian Wardlow ◽  
Agustin Pimstein ◽  
John R. Mecikalski ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Land Surface ◽  
Drought Index ◽  
Temporal Correlation ◽  
Meteorological Drought ◽  
Rainfall Data ◽  
Added Value ◽  
Stress Index ◽  
Drought Indices ◽  
Shallow Water Table

Abstract The reliability of standard meteorological drought indices based on measurements of precipitation is limited by the spatial distribution and quality of currently available rainfall data. Furthermore, they reflect only one component of the surface hydrologic cycle, and they cannot readily capture nonprecipitation-based moisture inputs to the land surface system (e.g., irrigation) that may temper drought impacts or variable rates of water consumption across a landscape. This study assesses the value of a new drought index based on remote sensing of evapotranspiration (ET). The evaporative stress index (ESI) quantifies anomalies in the ratio of actual to potential ET (PET), mapped using thermal band imagery from geostationary satellites. The study investigates the behavior and response time scales of the ESI through a retrospective comparison with the standardized precipitation indices and Palmer drought index suite, and with drought classifications recorded in the U.S. Drought Monitor for the 2000–09 growing seasons. Spatial and temporal correlation analyses suggest that the ESI performs similarly to short-term (up to 6 months) precipitation-based indices but can be produced at higher spatial resolution and without requiring any precipitation data. Unique behavior is observed in the ESI in regions where the evaporative flux is enhanced by moisture sources decoupled from local rainfall: for example, in areas of intense irrigation or shallow water table. Normalization by PET serves to isolate the ET signal component responding to soil moisture variability from variations due to the radiation load. This study suggests that the ESI is a useful complement to the current suite of drought indicators, with particular added value in parts of the world where rainfall data are sparse or unreliable.

scholarly journals Are Australian Teachers Making the Grade? A Study of News Coverage of Naplan Testing

2015 ◽  
Vol 154 (1) ◽  
pp. 25-33 ◽  
Author(s):  
Kathryn Shine
Keyword(s):  
News Media ◽  
News Coverage ◽  
Developed Countries ◽  
Testing System ◽  
Journalism Education ◽  
Test Results ◽  
National Assessment ◽  
The Subject ◽  
Standardised Testing ◽  
And Training

The standardised testing of school children has been the subject of significant news media attention in recent years in many developed countries around the world. This article examines the reporting of annual National Assessment Program Literacy and Numeracy (NAPLAN) tests in three major Australian newspapers, with a particular focus on the portrayal of school teachers in the coverage. Overall, teachers were presented as strongly opposed to NAPLAN and the publication of test results, yet the newspapers themselves supported the tests as an important accountability measure. Teachers were depicted as trying to influence the testing system through teaching to the test and cheating. They were presented as generally inadequate as teachers, and were blamed for perceived failings in the educational system. These findings point to implications for teacher recruitment and retention, and for journalism education and training.

scholarly journals Metode Tutor Sebaya Berbantuan Whatsapp untuk Meningkatkan Hasil Uji Coba Ujian Nasional di SMK Negeri 1 Tanjungpandan

2019 ◽  
Vol 6 (2) ◽  
pp. 691-703
Author(s):  
Yuli Yulianti
Keyword(s):  
Peer Tutoring ◽  
Average Score ◽  
Learning Method ◽  
Test Results ◽  
Peer Tutors ◽  
National Examination ◽  
The Subject ◽  
The Difference ◽  
The Government ◽  
Academic Year

National Examination is one of the learning results assessment set by the Government, and is ruled at Minister of Education and Culture regulation Number 4 year 2018. The problem discussed in this study is the low percentage of students achieving Graduare Competence Standard/SKL 55 in the nationale examination tryout for mathematics. One of the alternatives to solve this problem is the Peer Tutoring learning method using Whatsapp Messenger application asisstance, in which the subject is grade 12 AP students of SMK Negeri 1 Tanjungpandan academic year of 2018/2019. The research method implemented is the classroom action research. The peer tutoring learning method using Whatsapp Messenger application asisstance was carried out both inside and outside the classroom by providing a smaller member whatsapp group and a  classroom whatsapp group. Each small group consists of 6 people in which there were 1-2 peer tutors. Based on the results of data analysis and discussion, there was an increase at the results of the tryout of mathematics national exam tryout for grade 12 AP students after peer tutoring learning method using whatsapp messenger application asisstance was applied, with the total increase up to 50%. This fact can be inferred from the difference of the test results percentage for the first tryout and the third tryout which is from 10% to 60%, while the average score is increased from 34.96 to 60.22 by 25.26 points.

Sign in / Sign up

Export Citation Format

Share Document