drought is one of the natural phenomena which occurs in all climates in different parts of the world. iran is located in the dry belt of the world. the increase of desertification, drought reoccurrence, and destruction by human in this geographical region needs more studies on spatial and temporal trend of rainfall. in this study, trends of climatic drought during 1975-76/ 2004-05 in seasonal a...

A streamflow drought event, defined by applying the threshold level approach on streamflow time series, is composed of three parameters: duration, severity and magnitude. This study reveals statistical characteristics on streamflow drought event parameters and detects spatial and temporal trends in the streamflow drought in terms of frequency, duration and severity in Nebraska. The studies are ...

hydrologic regime is highly dependent on climate change, as hydrologic cycle components are directly influenced by climatic conditions. this paper analyzes the impacts of climate change on the hydrologic regime of the atrak river basin in the northeast of iran. it drains to the caspian sea. the data collected at 11 hydrometeorological stations were examined to detect trends in hydroclimatologic...

the aim of this study was the analysis of discharge variations of two rivers i.e. qezelozan and shahroud, regarding the sustainable rice production in guilan province. to achieve this purpose four trend analysis tests including sen, mann-kendall, linear regression and spearman were used. in this study, river discharge data of 49 and 37 years for respectively qezelozan and shahroud rivers were u...

This chapter concerns rank tests for independence of two random variables. A form of locally most powerful test against particular alternative is derived and the most often used variants of this test are mentioned, namely the test of van der Waerden type, Spearman rank correlation coefficient, the quadrant test and the Kendall rank correlation coefficient, a member of non-linear rank statistics...

any planning for the future requires estimates of future conditions. it is possible to study changes over time series. in this study, changes of production and cultivated area of 17 field crops of khorasan razavi province in a 25-year period were determined with mann - kendall test, sen’s estimator slope and linear regression. analysis of the three tests showed that performance of 76.5% from yi...

Table 1. RMP and pilot study sampling stations. Table 2. RMP and pilot sampling events. Table 3. Trace element data available from sampling events 7–15 for model-based clustering of sampling sites. Table 4. Definition of a stratification scheme for the MIDAS transects in San Francisco Bay. Table 5. Sample SpaceStat output from an OLS ANOVA for ln-transformed chromium (event 13). Table 6. Summar...