Artykuły w czasopismach: „Annual maximum series”

7

Ng, Jing Lin, Soon Kim Tiang, Yuk Feng Huang, Nur Ilya Farhana Md Noh, and Ramez A. Al-Mansob. "Analysis of annual maximum and partial duration rainfall series." IOP Conference Series: Earth and Environmental Science 646, no. 1 (2021): 012039. http://dx.doi.org/10.1088/1755-1315/646/1/012039.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

8

Rosbjerg, D. "On the annual maximum distribution in dependent partial duration series." Stochastic Hydrology and Hydraulics 1, no. 1 (1987): 3–16. http://dx.doi.org/10.1007/bf01543906.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

9

Martins, Eduardo S., and Jery R. Stedinger. "Historical information in a generalized Maximum Likelihood Framework with partial duration and annual maximum series." Water Resources Research 37, no. 10 (2001): 2559–67. http://dx.doi.org/10.1029/2000wr000009.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

10

Chen, Xiaohong, Lijuan Zhang, C. Y. Xu, Jiaming Zhang, and Changqing Ye. "Hydrological Design of Nonstationary Flood Extremes and Durations in Wujiang River, South China: Changing Properties, Causes, and Impacts." Mathematical Problems in Engineering 2013 (2013): 1–10. http://dx.doi.org/10.1155/2013/527461.

Pełny tekst źródła

Streszczenie:

The flood-duration-frequency (QDF) analysis is performed using annual maximum streamflow series of 1–10 day durations observed at Pingshi and Lishi stations in southern China. The trends and change point of annual maximum flood flow and flood duration are also investigated by statistical tests. The results indicate that (1) the annual maximum flood flow only has a marginally increasing trend, whereas the flood duration exhibits a significant decreasing trend at the 0.10 significant level. The change point for the annual maximum flood flow series was found in 1991 and after which the mean maximum flood flow increased by 45.26%. (2) The period after 1991 is characterized by frequent and shorter duration floods due to increased rainstorm. However, land use change in the basin was found intensifying the increased tendency of annual maximum flow after 1991. And (3) under nonstationary environmental conditions, alternative definitions of return period should be adapted. The impacts on curve fitting of flood series showed an overall change of upper tail from “gentle” to “steep,” and the design flood magnitude became larger. Therefore, a nonstationary frequency analysis taking account of change point in the data series is highly recommended for future studies.

Style APA, Harvard, Vancouver, ISO itp.

11

Tan, Xuezhi, and Thian Yew Gan. "Nonstationary Analysis of Annual Maximum Streamflow of Canada." Journal of Climate 28, no. 5 (2015): 1788–805. http://dx.doi.org/10.1175/jcli-d-14-00538.1.

Pełny tekst źródła

Streszczenie:

Abstract Both natural climate change and anthropogenic impacts may cause nonstationarities in hydrological extremes. In this study, long-term annual maximum streamflow (AMS) records from 145 stations over Canada were used to investigate the nonstationary characteristics of AMS, which include abrupt changes and monotonic temporal trends. The nonparameteric Pettitt test was applied to detect abrupt changes, while temporal monotonic trend analysis in AMS series was conducted using the nonparameteric Mann–Kendall and Spearman tests, as well as a parametric Pearson test. Nonstationary frequency analysis of the AMS series was done using a group of nonstationary probability distributions. The nonstationary characteristics of Canadian AMS were further investigated in terms of the Hurst exponent (H), which represents the long-term persistence (LTP) of streamflow data. The results presented here indicate that for Canadian AMS data, abrupt changes are detected more frequently than monotonic trends, partly because many rivers began to be regulated in the twentieth century. Drainage basins that have experienced significant land-use changes are more likely to show temporal trends in AMS, compared to pristine basins with stable land-use conditions. The nonstationary characteristics of AMS were accounted for by fitting the data with probability distributions with time-varying parameters. Large H found in almost ⅔ of the Canadian AMS dataset indicates strong LTP, which may partly represent the presence of long-term memories in many Canadian river basins. Furthermore, H values of AMS data are positively correlated with the basin area of Canadian rivers. It seems that nonstationary frequency analysis, instead of the traditional stationary hydrologic frequency analysis, should be employed in the future.

Style APA, Harvard, Vancouver, ISO itp.

12

Romanyuk, Romanyuk M. S., and O. I. Lukіanets. "ANALYSIS OF RECURRENCE OF RAIN FLOODS ON RIVERS IN THE TISZA BASIN (WITHIN UKRAINE)." Hydrology, hydrochemistry and hydroecology, no. 2(64) (2022): 22–29. http://dx.doi.org/10.17721/2306-5680.2022.2.2.

Pełny tekst źródła

Streszczenie:

Rain floods on the rivers in the Tisza basin within Ukraine are formed several times during the entire warm period. The purpose of the presented study is a detailed analysis of the frequency of such floods on the rivers of the region under study in terms of the series of annual maximum average daily water discharges and the series of maximum average daily discharges of partial probability. The first series, called the “multi-annual series”, includes only one of the highest discharges each year, in our case, one for the warm period – May-October. The second row includes all values hat exceed some limit value, which corresponds to the smallest value from the series of annual maximum annual water discharges. To carry out the work, we used observational data on the average daily water flow from the following hydrological posts on the rivers: the Uzh River – Uzhgorod, the Latoritsa River – Mukachevo, the Rika River – Mezhgorye, the Teresva River – Ust-Chernaya, the Tisza River – Rakhiv for the observation period 1946 (47 ) to 2019. To obtain the long-term series and partial probability necessary for the study, first, chronological samples of rain flood maxima were formed for both series separately, then they were ranked and the estimated return period was determined for each member of the series. The series of maximums of partial probability according to the data from the studied hydrological stations in their number on average 4-6 times exceed the number of values of the series of annual maxima. The calculated return periods are determined by the inverse formula to the Weibull formula. Graphs of the frequency of rain floods by annual maxima and maxima of partial probability for the stations under study were constructed, which made it possible to notice the following features: 1) the discharges maxima of rain floods with a frequency of less than 5-10 years differ for a number of annual maximum water discharges and a series of partial probability; 2) partial probability series better describe minor floods, especially those with a short return period. The analysis of the frequency of rain floods on the rivers in the Tisza basin within Ukraine made it possible to estimate the possible magnitudes of rain floods that can form during a warm period of time and to estimate their frequency of a certain magnitude. This is of practical interest as knowledge of potential floods can be used to assess the nature of potential floods in the future.

Style APA, Harvard, Vancouver, ISO itp.

13

Bărbulescu, Alina, and Dumitriu Cristian Ștefan. "On the Fractal Characteristics of Some Meteorological Extreme Series Recorded at Constanta, Romania." Ovidius University Annals of Constanta - Series Civil Engineering 23, no. 1 (2021): 77–82. http://dx.doi.org/10.2478/ouacsce-2021-0009.

Pełny tekst źródła

Streszczenie:

Abstract The study of hydro-meteorological series is important for planning agricultural activities, managing water resources, and taking measures to prevent the effects of natural hazards. Therefore, here we analyze the fractal characteristics of the temperature series recorded at Constanta, Romania. The studied series are the annual mean maximum annual and minimum annual temperatures recorded during 1961-2018.

Style APA, Harvard, Vancouver, ISO itp.

14

Park, Minkyu, Chulsang Yoo, Hyeonjun Kim, and Changhyun Jun. "Bivariate Frequency Analysis of Annual Maximum Rainfall Event Series in Seoul, Korea." Journal of Hydrologic Engineering 19, no. 6 (2014): 1080–88. http://dx.doi.org/10.1061/(asce)he.1943-5584.0000891.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

15

Back, Álvaro J., Augusto C. Pola, Nilzo I. Ladwig, and Hugo Schwalm. "Erosive rainfall in the Rio do Peixe Valley: Part III - Risk of extreme events." Revista Brasileira de Engenharia Agrícola e Ambiental 22, no. 1 (2018): 63–68. http://dx.doi.org/10.1590/1807-1929/agriambi.v22n1p63-68.

Pełny tekst źródła

Streszczenie:

ABSTRACT Understanding the risks of extreme events related to soil erosion is important for adequate dimensioning of erosion and runoff control structures. The objective of this study was to determine the rainfall erosivity with different return periods for the Valley of the Rio do Peixe in Santa Catarina state, Brazil. Daily pluviographic data series from 1984 to 2014 from the Campos Novos, and Videira meteorological stations and from 1986 to 2014 from the Caçador station were used. The data series of maximum annual rainfall intensity in 30 min, maximum annual erosive rainfall, and total annual erosivity were analyzed for each station. The Gumbel-Chow distributions were adjusted and their adhesions were evaluated by the Kolmogorov-Smirnov test at a significance level of 5%. The Gumbel-Chow distribution was adequate for the estimation of all studied variables. The mean annual erosivity corresponds to the return period of 2.25 years. The data series of the annual maximum individual rainfall erosivity coefficients varied from 47 to 50%.

Style APA, Harvard, Vancouver, ISO itp.

16

Jeneiová, Katarína, Silvia Kohnová, and Miroslav Sabo. "Detecting Trends in the Annual Maximum Discharges in the Vah River Basin, Slovakia." Acta Silvatica et Lignaria Hungarica 10, no. 2 (2014): 133–44. http://dx.doi.org/10.2478/aslh-2014-0010.

Pełny tekst źródła

Streszczenie:

Abstract A number of floods have been observed in the Slovak Republic in recent years, thereby raising awareness of and concern about flood risks. The paper focuses on the trend detection in the annual maximum discharge series in the Vah River basin located in Slovak Republic. Analysis was performed on data obtained from 59 gauging stations with minimum lengths of the observations from 40 years to 109 years. Homogeneity of the time series was tested by Alexandersson test for single shift at 5% level of significance. The Mann-Kendall trend test and its correction for autocorrelated data by Hamed and Rao (1998) were used to analyse the significance of detected changes in discharges. The series were analysed at different lengths of 40, 50, 60 years and whole observation period. Statistically significant rising and decreasing trends in the annual maximum discharge series were found in different regions of the Vah River catchments

Style APA, Harvard, Vancouver, ISO itp.

17

Wang, Wen, Xiao-Gang Wang, and Xuan Zhou. "Impacts of Californian dams on flow regime and maximum/minimum flow probability distribution." Hydrology Research 42, no. 4 (2011): 275–89. http://dx.doi.org/10.2166/nh.2011.137.

Pełny tekst źródła

Streszczenie:

Dams have major impacts on river hydrology with a general tendency to decrease annual maximum flows and increase annual minimum flows. The analysis of 41 streamflow series in California, USA are examined, and the results show that, as expected, the mean values and variations of annual peak flows and maximum flows of different durations are reduced for almost all sites after dam use, and the larger the ratio of total reservoir capacity to pre-dam annual runoff, the larger the rate of peak flow reduction. However, the impacts on minimum flow are mixed. For five out of seven cases with long data records for periods before and after dam use, the average annual minimum flow as well as its variation increased, but for the other two cases, they decreased. No significant changes are detected for various extreme precipitation indices; therefore, dam construction is believed to be the major reason for flow regime changes. The probability distribution of extreme flows also changed, due to the impacts of dams. The Log-Pearson Type III (LP3) distribution is best for peak flow series and one-day maximum series at sites with or without the impact of dams; the three-parameter Weibull (W3) distribution is the best model for the seven-day minimum flow at sites with no or minor dam impacts, whereas at sites with major dam impacts, the best model is the generalized extreme value (GEV) model for the seven-day minimum flow.

Style APA, Harvard, Vancouver, ISO itp.

18

Arrieta-Pastrana, Alfonso, Manuel Saba, and Adriana Puello Alcázar. "Analysis of Climate Variability and Climate Change in Sub-Daily Maximum Intensities: A Case Study in Cartagena, Colombia." Atmosphere 14, no. 1 (2023): 146. http://dx.doi.org/10.3390/atmos14010146.

Pełny tekst źródła

Streszczenie:

The present work analyses a time series of maximum intensities for sub-daily durations of 10 min, 20 min, up to 100 min, and their relationship with the maximum rainfall observations in twenty-four hours (P24), the total annual rainfall (PT), and the maximum, average, and minimum temperatures, using the records of the Rafael Núñez Airport station in the city of Cartagena de Indias, recorded from 1970 to 2015. The series of maximum intensities were obtained from the pluviographic records existing in the station. The analysis seeks to find evidence of climate change and climate variability. The series were tested for homogeneity, stationarity, trend, and periodicity. The degree of cross-correlation and temporal correlation between the different series were determined. Temperature series show homogeneity problems, while no correlation was found between the temperatures and the maximum sub-daily intensities, with the maximum rainfall observations in twenty-four hours and the total annual rainfall. The presence of marked periodicities was found in all the series, with a greater signal in the maximum. No significant trends were found in any of the series. Intensities and maximum rainfall observations in 24 h were found. In general, the series are stationary and do not show trends. Non-homogeneities in the series and the presence of periodicities can lead to an interpretation of non-stationarity and trend.

Style APA, Harvard, Vancouver, ISO itp.

19

Nakaegawa, Tosiyuki, Takuro Kobashi, and Hirotaka Kamahori. "Characteristics of Extreme Value Statistics of Annual Maximum Monthly Precipitation in East Asia Calculated Using an Earth System Model of Intermediate Complexity." Atmosphere 11, no. 12 (2020): 1273. http://dx.doi.org/10.3390/atmos11121273.

Pełny tekst źródła

Streszczenie:

Extreme precipitation is no longer stationary under a changing climate due to the increase in greenhouse gas emissions. Nonstationarity must be considered when realistically estimating the amount of extreme precipitation for future prevention and mitigation. Extreme precipitation with a certain return level is usually estimated using extreme value analysis under a stationary climate assumption without evidence. In this study, the characteristics of extreme value statistics of annual maximum monthly precipitation in East Asia were evaluated using a nonstationary historical climate simulation with an Earth system model of intermediate complexity, capable of long-term integration over 12,000 years (i.e., the Holocene). The climatological means of the annual maximum monthly precipitation for each 100-year interval had nonstationary time series, and the ratios of the largest annual maximum monthly precipitation to the climatological mean had nonstationary time series with large spike variations. The extreme value analysis revealed that the annual maximum monthly precipitation with a return level of 100 years estimated for each 100-year interval also presented a nonstationary time series which was normally distributed and not autocorrelated, even with the preceding and following 100-year interval (lag 1). Wavelet analysis of this time series showed that significant periodicity was only detected in confined areas of the time–frequency space.

Style APA, Harvard, Vancouver, ISO itp.

20

Jiang, Shangwen, and Ling Kang. "Flood frequency analysis for annual maximum streamflow using a non-stationary GEV model." E3S Web of Conferences 79 (2019): 03022. http://dx.doi.org/10.1051/e3sconf/20197903022.

Pełny tekst źródła

Streszczenie:

Under changing environment, the streamflow series in the Yangtze River have undergone great changes and it has raised widespread concerns. In this study, the annual maximum flow (AMF) series at the Yichang station were used for flood frequency analysis, in which a time varying model was constructed to account for non-stationarity. The generalized extreme value (GEV) distribution was adopted to fit the AMF series, and the Generalized Additive Models for Location, Scale and Shape (GAMLSS) framework was applied for parameter estimation. The non-stationary return period and risk of failure were calculated and compared for flood risk assessment between stationary and non-stationary models. The results demonstrated that the flow regime at the Yichang station has changed over time and a decreasing trend was detected in the AMF series. The design flood peak given a return period decreased in the non-stationary model, and the risk of failure is also smaller given a design life, which indicated a safer flood condition in the future compared with the stationary model. The conclusions in this study may contribute to long-term decision making in the Yangtze River basin under non-stationary conditions.

Style APA, Harvard, Vancouver, ISO itp.

21

Jamali, Sadegh, Arsalan Ghorbanian, and Abdulhakim M. Abdi. "Satellite-Observed Spatial and Temporal Sea Surface Temperature Trends of the Baltic Sea between 1982 and 2021." Remote Sensing 15, no. 1 (2022): 102. http://dx.doi.org/10.3390/rs15010102.

Pełny tekst źródła

Streszczenie:

The Baltic Sea is one of the fastest-warming marginal seas globally, and its temperature rise has adversely affected its physical and biochemical characteristics. In this study, forty years (1982–2021) of sea surface temperature (SST) data from the advanced very high resolution radiometer (AVHRR) were used to investigate spatial and temporal SST variability of the Baltic Sea. To this end, annual maximum and minimum SST stacked series, i.e., time series of stacked layers of satellite data, were generated using high-quality observations acquired at night and were fed to an automatic algorithm to detect linear and non-linear trend patterns. The linear trend pattern was the dominant trend type in both stacked series, while more pixels with non-linear trend patterns were detected when using the annual minimum SST. However, both stacked series showed increases in SST across the Baltic Sea. Annual maximum SST increased by an average of 0.062 ± 0.041 °C per year between 1982 and 2021, while annual minimum SST increased by an average of 0.035 ± 0.017 °C per year over the same period. Averaging annual maximum and minimum trends produces a spatial average of 0.048 ± 0.022 °C rise in SST per year over the last four decades.

Style APA, Harvard, Vancouver, ISO itp.

22

Zalina, M. D., M. N. M. Desa, V.-T.-A. Nguyen, and A. H. M. Kassim. "Selecting a probability distribution for extreme rainfall series in Malaysia." Water Science and Technology 45, no. 2 (2002): 63–68. http://dx.doi.org/10.2166/wst.2002.0028.

Pełny tekst źródła

Streszczenie:

This paper discusses the comparative assessment of eight candidate distributions in providing accurate and reliable maximum rainfall estimates for Malaysia. The models considered were the Gamma, Generalised Normal, Generalised Pareto, Generalised Extreme Value, Gumbel, Log Pearson Type III, Pearson Type III and Wakeby. Annual maximum rainfall series for one-hour resolution from a network of seventeen automatic gauging stations located throughout Peninsular Malaysia were selected for this study. The length of rainfall records varies from twenty-three to twenty-eight years. Model parameters were estimated using the L-moment method. The quantitative assessment of the descriptive ability of each model was based on the Probability Plot Correlation Coefficient test combined with root mean squared error, relative root mean squared error and maximum absolute deviation. Bootstrap resampling was employed to investigate the extrapolative ability of each distribution. On the basis of these comparisons, it can be concluded that the GEV distribution is the most appropriate distribution for describing the annual maximum rainfall series in Malaysia.

Style APA, Harvard, Vancouver, ISO itp.

23

Ghenim, Abderrahmane Nekkache, and Abdesselam Megnounif. "Variability and Trend of Annual Maximum Daily Rainfall in Northern Algeria." International Journal of Geophysics 2016 (2016): 1–11. http://dx.doi.org/10.1155/2016/6820397.

Pełny tekst źródła

Streszczenie:

The daily rainfall dataset of 35 weather stations covering the north of Algeria was studied for a period up to 43 years, recorded after 1970s. The variability and trends in annual maximum daily rainfall (AMDR) time series and their contributions in annual rainfall (AR) were investigated. The analysis of the series was based on statistical characteristics, Burn’s seasonality procedure, Mann-Kendall test, and linear regression technique. The contribution of the AMDR to AR analysis was subjected to both the Buishand test and the double mass curve technique. The AMDR characteristics reveal a strong temporal irregularity and have a wide frequency of occurrence in the months of November and December while the maximum intensity occurred in October. The observed phenomenon was so irregular that there was no dominant season and the occurrence of extreme event can arrive at any time of the year. The AMDR trends showed that only six of 35 stations have significant trend. For other stations, no clear trend was highlighted. This result was confirmed by the linear regression procedure. On the contrary, the contribution of AMDR in annual totals exhibited a significant increasing trend for 57% of the sites studied with a growth rate of up to 50%.

Style APA, Harvard, Vancouver, ISO itp.

24

Zhao, Xue Hua, and Li Li An. "Periodic Change of River Runoff Based on EMD-MES." Advanced Materials Research 250-253 (May 2011): 2848–51. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.2848.

Pełny tekst źródła

Streszczenie:

This paper discusses stabilizing treatment of runoff time series by empirical mode decomposition (EMD), and periodic analysis of stabilized runoff time series by maximum entropy spectrum, and presents high-resolution character of maximum entropy spectrum and its application prospect in hydrology. It conducts the analysis and calculation in combination with a real example of annual runoff series at the Lanzhou station in the upper of Yellow River, and study proves that annual runoff has 11.1, 6.25 and 3.1 years significant periods at the Lanzhou station. The conclusion illustrates the feasibility of this method and provides scientific data for water resources planning and managing.

Style APA, Harvard, Vancouver, ISO itp.

25

Westra, Seth, Lisa V. Alexander, and Francis W. Zwiers. "Global Increasing Trends in Annual Maximum Daily Precipitation." Journal of Climate 26, no. 11 (2013): 3904–18. http://dx.doi.org/10.1175/jcli-d-12-00502.1.

Pełny tekst źródła

Streszczenie:

Abstract This study investigates the presence of trends in annual maximum daily precipitation time series obtained from a global dataset of 8326 high-quality land-based observing stations with more than 30 years of record over the period from 1900 to 2009. Two complementary statistical techniques were adopted to evaluate the possible nonstationary behavior of these precipitation data. The first was a Mann–Kendall nonparametric trend test, and it was used to evaluate the existence of monotonic trends. The second was a nonstationary generalized extreme value analysis, and it was used to determine the strength of association between the precipitation extremes and globally averaged near-surface temperature. The outcomes are that statistically significant increasing trends can be detected at the global scale, with close to two-thirds of stations showing increases. Furthermore, there is a statistically significant association with globally averaged near-surface temperature, with the median intensity of extreme precipitation changing in proportion with changes in global mean temperature at a rate of between 5.9% and 7.7% K−1, depending on the method of analysis. This ratio was robust irrespective of record length or time period considered and was not strongly biased by the uneven global coverage of precipitation data. Finally, there is a distinct meridional variation, with the greatest sensitivity occurring in the tropics and higher latitudes and the minima around 13°S and 11°N. The greatest uncertainty was near the equator because of the limited number of sufficiently long precipitation records, and there remains an urgent need to improve data collection in this region to better constrain future changes in tropical precipitation.

Style APA, Harvard, Vancouver, ISO itp.

26

Yoo, Chulsang, Minkyu Park, Hyeon Jun Kim, and Changhyun Jun. "Comparison of annual maximum rainfall events of modern rain gauge data (1961–2010) and Chukwooki data (1777–1910) in Seoul, Korea." Journal of Water and Climate Change 9, no. 1 (2017): 58–73. http://dx.doi.org/10.2166/wcc.2017.110.

Pełny tekst źródła

Streszczenie:

Abstract In this study, the annual maximum rainfall event series were constructed and compared for both the modern flip-bucket type rainfall data, collected since 1961 (the modern data), and the old Chukwooki rainfall data, collected from 1777 to 1910 (the Chukwooki data). First, independent rainfall events were derived, by applying the same rainfall threshold of 2 mm and data collection time interval of 2 hours, to both the Chukwooki and the modern data. Annual maximum rainfall event series were then constructed, by applying Freund's bivariate exponential distribution annually. Finally, bivariate frequency analysis was done for the annual maximum rainfall event series constructed, by applying the bivariate logistic model to evaluate and quantify their characteristics. The results are in summary: (1) characteristics of the Chukwooki rainfall events and modern rainfall events are very similar to each other; (2) the annual maximum rainfall events of modern data are slightly larger than those of the Chukwooki data. The total rainfall depth per rainfall event for any given return period is thus estimated to be a little higher for the modern data than that of the Chukwooki data. However, based on the findings in this study, it could not be concluded that the rainfall characteristics have significantly changed during the last 200 years.

Style APA, Harvard, Vancouver, ISO itp.

27

Jónsdóttir, Jóna Finndís, Cintia B. Uvo, and Robin T. Clarke. "Trend analysis in Icelandic discharge, temperature and precipitation series by parametric methods." Hydrology Research 39, no. 5-6 (2008): 425–36. http://dx.doi.org/10.2166/nh.2008.002.

Pełny tekst źródła

Streszczenie:

This paper presents results of analyses by parametric methods of annual means of temperature, precipitation and discharge, and of seasonal maximum precipitation at 17, 28 and 10 Icelandic stations, respectively, for the period 1961–2000. Trends in mean seasonal temperature and precipitation are in broad agreement with results found by other authors using other methods. A positive trend appears in both mean annual temperature and mean temperatures in most seasons. Annual mean precipitation trends are positive in most seasons except for negative trends in the September–November season in the south. Additionally, positive trends appear in maximum one-, three- and five-day precipitation, both during the spring and autumn, except at a group of stations in central Iceland. Some of the positive trends in mean annual and seasonal precipitation may, however, be attributed to the positive trend in temperature which may have influenced gauge catch. Trends in mean annual and seasonal discharge are small and statistically insignificant; the trends found in temperature and precipitation do not all relate directly to trends in discharge but suggest hypotheses for further study of the relationships between them.

Style APA, Harvard, Vancouver, ISO itp.

28

Li, Guofang, Xinyi Xiang, and Caixiu Guo. "Analysis of Nonstationary Change of Annual Maximum Level Records in the Yangtze River Estuary." Advances in Meteorology 2016 (2016): 1–14. http://dx.doi.org/10.1155/2016/7205723.

Pełny tekst źródła

Streszczenie:

Under the impact of climate change and human activities, the stationarity of hydrometeorological extreme value series has been losing in many regions, which makes occurrence rules of hydrometeorological extreme events more complicated. In this study, the efficiencies of trend test methods such as Spearman rank correlation test and Mann-Kendall test, as well as the efficiencies of change-point test methods such as moving T test, moving rank sum test, Pettitt test, and sequential Mann-Kendall test were analyzed quantitatively through Monte Carlo simulation. Five representative level stations in the Yangtze River estuary were selected, and the methods listed above were used in the trend and change-point detection of the annual maximum tidal level records in the period of 1950–2008. It was found that obvious rising tendency existed in the annual maximum tidal level series for all these 5 stations, and year 1980 (for 3 stations) and year 1979 (for 2 stations) were statistically significant change-points. Two subseries were divided with the change-point as the dividing point for all these actual series in the stations. Frequency analyses were carried out, respectively, for all of the subseries, and the impact of nonstationary changes in annual maximum tidal levels on probability distribution was evaluated quantitatively.

Style APA, Harvard, Vancouver, ISO itp.

29

Khatun, Khadija, MA Samad, and Md Bazlur Rashid. "Time Series Analysis of Temperature and Rainfall Data of Dhaka Division." Dhaka University Journal of Science 65, no. 2 (2017): 119–23. http://dx.doi.org/10.3329/dujs.v65i2.54519.

Pełny tekst źródła

Streszczenie:

In this paper, thirty five years’ (1981-2015) temperature and rainfall data have been studied to detect the recent trends in temperature and rainfall over Dhaka division of Bangladesh. Data of climatic factors such as annual average maximum temperature (MAXT), minimum temperature (MINT), mean temperature (MEANT), monsoon total rainfall (MTR) and annual total rainfall (ATR) have been analyzed. Sen’s non-parametric estimator of slope has been frequently used to estimate the magnitude of trend, whose statistical significance is assessed by the Mann–Kendall test. For this purpose, data from four meteorological stations (Dhaka, Mymensingh, Tangail and Faridpur) have been used. It is observed that annual average maximum, minimum and mean temperature of the study area are increasing at the rates 0.0170C/year, 0.0090C/year and 0.0130C/year respectively and the upward trend is statistically stable with 10% level of significance. On the other hand, monsoon total rainfall and annual total rainfall are decreasing at the rates of 4.94 mm/year and 16.11mm/year respectively where the downward trend of MTR is insignificant but the trend of ATR is significant with 10% level of significance. Dhaka Univ. J. Sci. 65(2): 119-123, 2017 (July)

Style APA, Harvard, Vancouver, ISO itp.

30

Madsen, Henrik, Charles P. Pearson, and Dan Rosbjerg. "Comparison of annual maximum series and partial duration series methods for modeling extreme hydrologic events: 2. Regional modeling." Water Resources Research 33, no. 4 (1997): 759–69. http://dx.doi.org/10.1029/96wr03849.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

31

Hyvärinen, Veli. "Trends and Characteristics of Hydrological Time Series in Finland." Hydrology Research 34, no. 1-2 (2003): 71–90. http://dx.doi.org/10.2166/nh.2003.0029.

Pełny tekst źródła

Streszczenie:

Hydrological time series analyses made in Finland up to 2001 show the following: 1) Precipitation has been increasing in southern and central Finland, and also in the north in winter, during the period 1911-2000. There are, however, no harmonized analyses of areal precipitation to show the exact increase. 2) The annual maximum of the areal water equivalent of snow has been increasing in eastern and northern Finland but decreasing in the south and west during the period 1947-2001. 3) The winter runoff has generally been increasing strongly in southern and slightly in central Finland during the 20th century. In northern Lapland there are no signs of increase in winter or annual flow. Annual discharge in the south and west has also increased to some extent. 4) The existing analyses show no signs of long-term trends in annual evapotranspiration. 5) Long-term fluctuations of water stage have been observed in the major groundwater formations. 6) The series of the date of ice break-up in the river Tornionjoki - starting in 1693 – shows that in recent decades the ice cover of the river has broken up about two weeks earlier than in the beginning of the period. 6) Lake ice maximum thickness series show no noticeable trend. 7) Lake water temperature in south-eastern Finland seems to have been increasing slightly during the period starting in 1924; in central and northern Finland no trends in water temperature have been observed.

Style APA, Harvard, Vancouver, ISO itp.

32

Wu, Shuguang, Guigen Nie, Xiaolin Meng, et al. "Comparative Analysis of the Effect of the Loading Series from GFZ and EOST on Long-Term GPS Height Time Series." Remote Sensing 12, no. 17 (2020): 2822. http://dx.doi.org/10.3390/rs12172822.

Pełny tekst źródła

Streszczenie:

In order to investigate the effect of different loading models on the nonlinear variations in Global Positioning System (GPS) height time series, the characteristics of annual signals (amplitude and phase) of GPS time series, loading series from Deutsche GeoForschungsZentrum, Germany (GFZ) and School and Observatory of Earth Sciences, France (EOST) at 633 global GPS stations are processed and analyzed. The change characteristics of the root mean square (RMS) reduction rate, annual amplitude and phase of GPS time series after environmental loading corrections (ELCs) are then detected. Results show that ELCs have a positive effect on the reduction in the nonlinear deformation contained in most GPS stations around the world. RMS reduction rates are positive at 82.6% stations after GFZ correction and 87.4% after EOST correction, and the average reduction rates of all stations are 10.6% and 15.4%, respectively. As for the environmental loading series from GFZ and EOST, their average annual amplitudes are 2.7 and 3.1 mm, which explains ~40% annual amplitude of GPS height time series (7.2 mm). Further analysis of some specific stations indicates that the annual phase difference between GPS height time series and the environmental loading series is an important reason that affects the reduction rates of the RMS and annual amplitude. The linear relationship between the annual phase difference and the annual amplitude reduction rate is significant. The linear fitting results show that when there is no annual phase difference between GPS and loading series, the reduction rates of the RMS and annual amplitude will increase to the maximum of 15.6% and 41.6% for GFZ, and 22.0% and 46.6% for EOST.

Style APA, Harvard, Vancouver, ISO itp.

33

Karim, Fazlul, Masud Hasan, and Steve Marvanek. "Evaluating Annual Maximum and Partial Duration Series for Estimating Frequency of Small Magnitude Floods." Water 9, no. 7 (2017): 481. http://dx.doi.org/10.3390/w9070481.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

34

Park, Min-Kyu, and Chul-Sang Yoo. "Probabilistic Analysis of Independent Storm Events: 1. Construction of Annual Maximum Storm Event Series." Journal of Korean Society of Hazard Mitigation 11, no. 2 (2011): 127–36. http://dx.doi.org/10.9798/kosham.2011.11.2.127.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

35

Wu, Yunbiao, and Lianqing Xue. "Frequency Analysis and Uncertainty Assessment of Annual Maximum Flood Series Using Bayesian MCMC Method." IOP Conference Series: Materials Science and Engineering 392 (August 3, 2018): 062107. http://dx.doi.org/10.1088/1757-899x/392/6/062107.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

36

Aronica, G., M. Cannarozzo, and L. Noto. "Investigating the changes in extreme rainfall series recorded in an urbanised area." Water Science and Technology 45, no. 2 (2002): 49–54. http://dx.doi.org/10.2166/wst.2002.0026.

Pełny tekst źródła

Streszczenie:

The aim of this study is to investigate and quantify changes in the rainfall regime of the metropolitan area of Palermo characterised by increasingly strong urbanisation. The rainfall data, considered in this study, were collected on a yearly basis from eight rain gauges within and outside the metropolitan area of Palermo, Sicily, Italy. A preliminary analysis made on the annual total rainfall depths showed a global reduction of total annual rainfall, with two different trends: more regular for the series observed in the rain gauges within the urbanised area and more variable for the series observed in the rain gauges outside the area. A further analysis has been performed using the series of maximum intensity for fixed duration (1, 3, 6, 12, 24 hrs) and annual daily maxima. The analysis of the trend in the extreme rainfall series has been performed by estimating the maximum rainfall depth corresponding to a fixed return period using the EV1 distribution with parameters estimated using L-moments. The analysis of all series indicates a global reduction of rainfall intensities, both for internal and external series, in disagreement with the results obtained by other authors.

Style APA, Harvard, Vancouver, ISO itp.

37

Brown, Vincent M., Barry D. Keim, and Alan W. Black. "Trend Analysis of Multiple Extreme Hourly Precipitation Time Series in the Southeastern United States." Journal of Applied Meteorology and Climatology 59, no. 3 (2020): 427–42. http://dx.doi.org/10.1175/jamc-d-19-0119.1.

Pełny tekst źródła

Streszczenie:

AbstractAnnual trends in extreme hourly precipitation time series were examined at 50 first-order weather stations across the southeastern United States from 1960 to 2017. Results indicated that the magnitude of annual maximum 1-, 3-, 6-, 12-, and 18-h periods did not broadly change at the sites analyzed; however, the numerical value that defines a (station specific) 90th-percentile hourly accumulation significantly (p ≤ 0.05) increased at 36% (18/50) of the stations. No station had a significant decreasing trend in annual 90th-percentile hourly event magnitude. Stations in Texas observed the largest increase in annual 90th-percentile hourly event magnitude, where parameter estimates showed increases of 0.20%–0.26% per year. Annual average dry-spell duration, defined as the average number of hours between measurable precipitation events, significantly decreased at 18% (9/50) of sites analyzed. Parameter estimates from regression performed on average dry-spell-duration time series showed decreases of roughly 0.11%–0.19% per year for the stations across southern Florida. Six stations across Georgia showed significant decreasing trends in the annual maximum consecutive hourly period with measurable precipitation (duration), demonstrating that the longest precipitation events that occurred at these stations have decreased in duration since 1960.

Style APA, Harvard, Vancouver, ISO itp.

38

Mediero, Luis. "Identification of Flood-Rich and Flood-Poor Periods by Using Annual Maximum Series of Floods in Spain." Proceedings 7, no. 1 (2018): 15. http://dx.doi.org/10.3390/ecws-3-05829.

Pełny tekst źródła

Streszczenie:

Currently, there is general concern about the non-stationary behaviour of flood series. Consequently, several studies have been conducted to identify large-scale patterns of change in such flood series. In Spain, a general decreasing trend was found in the period 1959–2009. However, a multi-temporal trend analysis, with varying starting and ending years, showed that trend signs depended on the period considered. Flood oscillations could influence the results, especially when flood-rich and flood-poor periods are located at the beginning or end of the series. In Spain, a flood- rich period in 1950–1970 seemed to lead to the generalised decreasing trend, as it was located at the beginning of the flood series. Nevertheless, the multi-temporal test can only find potential flood- rich and flood-poor periods qualitatively. A methodology has been developed to identify statistically significant flood-rich and flood-poor periods. The expected variability of floods under the stationarity assumption is compared with the variability of floods in observed flood series. The methodology is applied to the longest streamflow series available in Spain. Seven gauging stations located in near-natural catchments, with continuous observations in the period 1942–2014, are selected. Both annual maximum and peak-over-threshold series are considered. Flood-rich and flood-poor periods in terms of flood magnitudes and the annual count of exceedances over a given threshold are identified. A flood-rich period in the beginning of the series and a flood-poor period at its end are identified in most of the selected sites. Accordingly, a flood-rich period placed at the beginning of the series, followed by a flood-poor period, influence the generalised decreasing trend in the flood series previously found in Spain.

Style APA, Harvard, Vancouver, ISO itp.

39

Vieira, Felipe Rodolfo, Michael Silveira Thebaldi, Bruno Gonçalves Silveira, and Virgílio Henrique Barros Nogueira. "PROBABLE RAINFALL OF DIVINÓPOLIS CITY, MINAS GERAIS STATE, BRAZIL." REVISTA ENGENHARIA NA AGRICULTURA - REVENG 28 (February 5, 2020): 89–99. http://dx.doi.org/10.13083/reveng.v28i.6385.

Pełny tekst źródła

Streszczenie:

The aim of this paper was to analyze the behavior of non-parametric statistical distributions on the prediction of probable monthly and total annual rainfall as well as to determine the monthly and annual probable rainfall with different levels of probability for Divinópolis, Minas Gerais State, Brazil. The analysis consisted in adjusting the theoretical probability distribution to a data series of 66 years of monthly and annual rainfall. The data were obtained from the Hidroweb service, controlled by the National Water Agency (ANA, in Portuguese). The frequency distributions of Gumbel for Maximus, Fréchet and Gamma were adjusted to the observed series, where the adherence of these models to the data were tested by the Kolmogorov-Smirnov and Chi-Squared test, both with 5% of probability. The model that best represented, in most cases, the frequency distributions of the series of total monthly precipitation was Gumbel for Maximus, while the Fréchet model had the worst result, not fitting to the data of the historical series for both tests performed in the study. The probable monthly maximum precipitation for Divinópolis is 527 mm, associated with a probability of 5% and for January, while the lowest one is 0.0042 mm, with probability of 95% in July.

Style APA, Harvard, Vancouver, ISO itp.

40

Bonaccorso, B., A. Cancelliere, and G. Rossi. "Detecting trends of extreme rainfall series in Sicily." Advances in Geosciences 2 (February 21, 2005): 7–11. http://dx.doi.org/10.5194/adgeo-2-7-2005.

Pełny tekst źródła

Streszczenie:

Abstract. The objective of the study is to assess the presence of linear and non linear trends in annual maximum rainfall series of different durations observed in Sicily. In particular, annual maximum rainfall series with at least 50 years of records starting from the 1920’s are selected, and for each duration (1, 3, 6, 12 and 24 h) the Student’s t test and theMann- Kendall test, respectively, for linear and non linear trend detection, are applied also by means of bootstrap techniques. The effect of trend on the assessment of the return period of a critical event is also analysed. In particular, return periods related to a storm, recently occurred along the East Coast of Sicily, are computed by estimating parameters based on several sub-series extracted from the whole observation period. Such return period estimates are also compared with confidence intervals computed by bootstrap. Results indicate that for shorter durations, the investigated series generally exhibit increasing trends while as longer durations are considered, more and more series exhibit decreasing trends.

Style APA, Harvard, Vancouver, ISO itp.

41

Zeng, Ling, Hongwei Bi, Yu Li, Xiulin Liu, Shuai Li, and Jinfeng Chen. "Nonstationary Annual Maximum Flood Frequency Analysis Using a Conceptual Hydrologic Model with Time-Varying Parameters." Water 14, no. 23 (2022): 3959. http://dx.doi.org/10.3390/w14233959.

Pełny tekst źródła

Streszczenie:

Recent evidence of the impact of watershed underlying conditions on hydrological processes have made the assumption of stationarity widely questioned. In this study, the temporal variations of frequency distributions of the annual maximum flood were investigated by continuous hydrological simulation considering nonstationarity for Weihe River Basin (WRB) in northwestern China. To this end, two nonstationary versions of the GR4J model were introduced, where the production storage capacity parameter was regarded as a function of time and watershed conditions (e.g., reservoir storage and soil-water conservation land area), respectively. Then the models were used to generate long-term runoff series to derive flood frequency distributions, with synthetic rainfall series generated by a stochastic rainfall model as input. The results show a better performance of the nonstationary GR4J model in runoff simulation than the stationary version, especially for the annual maximum flow series, with the corresponding NSE metric increasing from 0.721 to 0.808. The application of the nonstationary flood frequency analysis indicates the presence of significant nonstationarity in the flood quantiles and magnitudes, where the flood quantiles for an annual exceedance probability of 0.01 range from 4187 m3/s to 8335 m3/s for the past decades. This study can serve as a reference for flood risk management in WRB and possibly for other basins undergoing drastic changes caused by intense human activities.

Style APA, Harvard, Vancouver, ISO itp.

42

Santos, Hugo Thaner dos, and Sérgio Nascimento Duarte. "HEAVY RAINFALL EVENTS IN VOLTA REDONDA." IRRIGA 26, no. 4 (2021): 801–13. http://dx.doi.org/10.15809/irriga.2021v26n4p801-813.

Pełny tekst źródła

Streszczenie:

Most Brazilian cities do not manage urban drainage in a proper manner, due to lack of planning in the sector or of easy-to-consult literature about local hydrology to enable hydrological modeling. Volta Redonda County fits this statistic, since it experiences events associated with flood and inundation in some specific sites. The aims of the present study are: (i) to record a series of maximum annual daily rainfall events in Volta Redonda County and to investigate whether their intensity has increased over the years; (ii) to adjust the maximum daily annual rainfall to a probability distribution model and to generate a heavy rainfall table for Volta Redonda County to enable dimensioning surface drainage systems. Seventy-seven years of rainfall data from a local station were used in the current study - maximum daily annual rainfall was calculated. Mann-Kendell test was applied to this series in order to check its stationarity over time. Then, Gumbel distribution was adjusted to the maximum annual data to allow its extrapolation. Finally, daily data were transformed into shorter rainfall values, at return period ranging from 2 to 500 years. Volta Redonda rainfall series can be considered stationary; results in the present research can be used to build rainwater drainage systems in Volta Redonda County; it is recommended using mean intensity of 150 mm h-1 for small urban drainage structures, whenever it is not possible determining their surface runoff concentration time.

Style APA, Harvard, Vancouver, ISO itp.

43

Islam, M. S., and M. B. Sikder. "Detection of Trend in Hydrologic Variables Using Non-Parametric Test: A Study on Surma River in Northeastern Bangladesh." Journal of Scientific Research 9, no. 3 (2017): 277–84. http://dx.doi.org/10.3329/jsr.v9i3.32560.

Pełny tekst źródła

Streszczenie:

An initiative has been taken to investigate the trends in discharge and water level (WL) of the Surma River in northeastern Bangladesh. The daily time series data of discharge and WL from two stations named Kanairghat and Sylhet with a period of 42 years (1973 2014) and 35 years (1980 2014) respectively have been analyzed. Non parametric Mann-Kendall Test has been applied to detect the trend and Sens slope estimator is used to measure the slope of the trends. In Kanairghat station, annual mean WL has significant trend (P: 0.03); while, annual mean discharge, mean monsoon discharge, annual maximum discharge, mean monsoon WL, and annual maximum WL shows insignificant trend (P: 0.24, 0.46, 0.14, 0.05, and 0.12). In Sylhet station, annual mean discharge, annual maximum discharge, and annual mean WL have significant trend (P: 0.03, 0.004, and 0.02). In other hand, mean monsoon discharge, mean monsoon WL, and annual maximum WL in Sylhet station has insignificant trend (P: 0.46, 0.13, and 0.21). According to Sens slope statistics, all of the detected trends, except annual maximum WL at Sylhet station, are downward. This study recommends a comprehensive water management scheme should be taken to ensure sustainable use of the river water.

Style APA, Harvard, Vancouver, ISO itp.

44

Sordo-Ward, Alvaro, Ivan Gabriel-Martín, Paola Bianucci, Giuseppe Mascaro, Enrique R. Vivoni, and Luis Garrote. "Stochastic Hybrid Event Based and Continuous Approach to Derive Flood Frequency Curve." Water 13, no. 14 (2021): 1931. http://dx.doi.org/10.3390/w13141931.

Pełny tekst źródła

Streszczenie:

This study proposes a methodology that combines the advantages of the event-based and continuous models, for the derivation of the maximum flow and maximum hydrograph volume frequency curves, by combining a stochastic continuous weather generator (the advanced weather generator, abbreviated as AWE-GEN) with a fully distributed physically based hydrological model (the TIN-based real-time integrated basin simulator, abbreviated as tRIBS) that runs both event-based and continuous simulation. The methodology is applied to Peacheater Creek, a 64 km2 basin located in Oklahoma, United States. First, a continuous set of 5000 years’ hourly weather forcing series is generated using the stochastic weather generator AWE-GEN. Second, a hydrological continuous simulation of 50 years of the climate series is generated with the hydrological model tRIBS. Simultaneously, the separation of storm events is performed by applying the exponential method to the 5000- and 50-years climate series. From the continuous simulation of 50 years, the mean soil moisture in the top 10 cm (MSM10) of the soil layer of the basin at an hourly time step is extracted. Afterwards, from the times series of hourly MSM10, the values associated to all the storm events within the 50 years of hourly weather series are extracted. Therefore, each storm event has an initial soil moisture value associated (MSM10Event). Thus, the probability distribution of MSM10Event for each month of the year is obtained. Third, the five major events of each of the 5000 years in terms of total depth are simulated in an event-based framework in tRIBS, assigning an initial moisture state value for the basin using a Monte Carlo framework. Finally, the maximum annual hydrographs are obtained in terms of maximum peak-flow and volume, and the associated frequency curves are derived. To validate the method, the results obtained by the hybrid method are compared to those obtained by deriving the flood frequency curves from the continuous simulation of 5000 years, analyzing the maximum annual peak-flow and maximum annual volume, and the dependence between the peak-flow and volume. Independence between rainfall events and prior hydrological soil moisture conditions has been proved. The proposed hybrid method can reproduce the univariate flood frequency curves with a good agreement to those obtained by the continuous simulation. The maximum annual peak-flow frequency curve is obtained with a Nash–Sutcliffe coefficient of 0.98, whereas the maximum annual volume frequency curve is obtained with a Nash–Sutcliffe value of 0.97. The proposed hybrid method permits to generate hydrological forcing by using a fully distributed physically based model but reducing the computation times on the order from months to hours.

Style APA, Harvard, Vancouver, ISO itp.

45

Madsen, Henrik, Peter F. Rasmussen, and Dan Rosbjerg. "Comparison of annual maximum series and partial duration series methods for modeling extreme hydrologic events: 1. At-site modeling." Water Resources Research 33, no. 4 (1997): 747–57. http://dx.doi.org/10.1029/96wr03848.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

46

Pekárová, Pavla, Jakub Mészáros, Pavol Miklánek, Ján Pekár, Stevan Prohaska, and Aleksandra Ilić. "Long-Term Runoff Variability Analysis of Rivers in the Danube Basin." Acta Horticulturae et Regiotecturae 24, s1 (2021): 37–44. http://dx.doi.org/10.2478/ahr-2021-0008.

Pełny tekst źródła

Streszczenie:

Abstract The long-term runoff variability is identified to consist of the selected large rivers with long-term data series in the Danube River Basin. The rivers were selected in different regions of the Danube River Basin and have a large basin area (Danube: Bratislava gauge with 131,338 km2; Tisza: Senta with 141,715 km2; and Sava: Sremska Mitrovica with 87,966 km2). We worked with the station Danube: Reni in the delta as well. A spectral analysis was used to identify the long-term variability of three different types of time series: (1) Average annual discharge time series, (2) Minimum annual discharge time series and (3) Maximum annual discharge time series. The results of the study can be used in a long-term forecast of the runoff regime in the future.

Style APA, Harvard, Vancouver, ISO itp.

47

Pashynskyi, Mykola, Victor Pashynskyi, and Evgeniy Klymenko. "CALCULATION OF CLIMATE LOADS DESIGN VALUES ACCORDING TO THE PROBABILITY MODEL OF ANNUAL MAXIMUM SERIES." Elektronički časopis građevinskog fakulteta Osijek 12, no. 23 (2021): 61–71. http://dx.doi.org/10.13167/2021.23.6.

Pełny tekst źródła

Streszczenie:

The aim of this work is to improve a method for determining the characteristic values of climatic loads according to a probabilistic model of the annual maxima sequence, by choosing a rational type of generalized extreme value distribution law. An analysis is provided regarding the suitability of using four types of distributions for describing a data collection of maximum values of climatic loads. Using example data from the meteorological stations of Ukraine, it is found that for coefficients of variation smaller than 0.85–1.0, it is advisable to use the double exponential Gumbel distribution (generalized extreme value distribution type-I), and at higher values of the coefficient of variation, it is advisable to use the Weibull distribution (generalized extreme value distribution type-III). Recommendations are provided for considering the accuracy in the estimations of the characteristic values of loads according to the probabilistic model for the annual maximum value series.

Style APA, Harvard, Vancouver, ISO itp.

48

Amirabadizadeh, Mahdi, Yuk Feng Huang, and Teang Shui Lee. "Recent Trends in Temperature and Precipitation in the Langat River Basin, Malaysia." Advances in Meteorology 2015 (2015): 1–16. http://dx.doi.org/10.1155/2015/579437.

Pełny tekst źródła

Streszczenie:

A study was undertaken to detect long-term trends in the annual and seasonal series of maximum and minimum temperatures. Measurements were taken at 11 meteorological stations located in the Langat River Basin in Malaysia. The rainfall and maximum and minimum temperature data were obtained from the Malaysia Meteorological Department (MMD) and the Department of Irrigation and Drainage (DID) Malaysia. The procedures used included the Mann-Kendall test, the Mann-Kendall rank statistic test, and the Theil-Sen’s slope method. The analytical results indicated that when there were increasing and decreasing trends in the annual and seasonal precipitation and temperature, only the increasing trends were significant at the 95% confidence level. The Theil-Sen’s slope method showed that the rate of increment in the annual precipitation is greater than the seasonal precipitation. A bootstrap technique was applied to explore uncertainty about significant slope values for rainfall, as well as the maximum and minimum temperatures. The Mann-Kendall rank statistics test indicated that most of the trends in the annual and seasonal time series started in the year 2000. All of the annual and seasonal significant trends were obtained at the stations located in the north, east, and northeast portions of the Langat River Basin.

Style APA, Harvard, Vancouver, ISO itp.

49

Castillo-Mateo, Jorge, Jesús Asín, Ana C. Cebrián, Jesús Mateo-Lázaro, and Jesús Abaurrea. "Bayesian Variable Selection in Generalized Extreme Value Regression: Modeling Annual Maximum Temperature." Mathematics 11, no. 3 (2023): 759. http://dx.doi.org/10.3390/math11030759.

Pełny tekst źródła

Streszczenie:

In many applications, interest focuses on assessing relationships between covariates and the extremes of the distribution of a continuous response. For example, in climate studies, a usual approach to assess climate change has been based on the analysis of annual maximum data. Using the generalized extreme value (GEV) distribution, we can model trends in the annual maximum temperature using the high number of available atmospheric covariates. However, there is typically uncertainty in which of the many candidate covariates should be included. Bayesian methods for variable selection are very useful to identify important covariates. However, such methods are currently very limited for moderately high dimensional variable selection in GEV regression. We propose a Bayesian method for variable selection based on a stochastic search variable selection (SSVS) algorithm proposed for posterior computation. The method is applied to the selection of atmospheric covariates in annual maximum temperature series in three Spanish stations.

Style APA, Harvard, Vancouver, ISO itp.

50

Marsh, Terry, and Catherine L. Harvey. "The Thames flood series: a lack of trend in flood magnitude and a decline in maximum levels." Hydrology Research 43, no. 3 (2012): 203–14. http://dx.doi.org/10.2166/nh.2012.054.

Pełny tekst źródła

Streszczenie:

The flow series for the River Thames near its tidal limit is one of the most studied in the world. Its length and completeness, and the richness of the historical information which augments the formal flow record, ensures that the series is of immense value. However, the variability in flood magnitude and frequency that it captures needs to be interpreted with caution. The homogeneity of the time series is influenced by a wide range of factors, including changes in the hydrometric capability of the gauging station and the impact of differing water, river and land management practices on the flow regime. Nevertheless, both the daily flow series and the record of lock levels provide some reassuring signals regarding the resilience of the Thames to fluvial flood risk in a warming world. Since routine flow measurement began in 1883, the Thames basin has seen a substantial rise in air temperature and a tendency for both winter rainfall and annual runoff to increase. There is no trend in fluvial flood magnitude however, partly reflecting a decline in snowmelt contributions to major floods and annual maximum lock levels show a significant decline, reflecting a highly sustained programme of river management.

Style APA, Harvard, Vancouver, ISO itp.

Artykuły w czasopismach na temat „Annual maximum series”

Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych