drought is a climatological hazard and is a part of the climate of a region. this climatological phenomenon has some properties that distinguish it from other natural disasters. drought is a gradual phenomenon and when the amount of moisture and precipitation become less than normal value in a certain period, its damages are non- structural in this condition and it is said that drought has occu...

drought is a normal, recurring feature of climate phenomena; it may occur virtually in all climatic regions. the effects of drought accumulate slowly and its impacts are spread over a larger geographical area than other natural hazards. drought is a natural hazard originating from a deficiency of precipitation that result in a water shortage for some activities or some groups and is often assoc...

the present study examined year-to-year variations in areas affected by drought during a period of 39 water yearsin iran. ninety-five meteorological stations were chosen to provide near-continuous long-term records, althoughsome data was missing (less than 10%). the missing data points were estimated using a linear correlation methodbetween the reference station with the missing data points and...

Drought duration and severity are two properties that are usually needed for drought analysis. To characterize the correlation between the two drought properties, a bivariate distribution is needed. A new method based on entropy theory is proposed for constructing the bivariate distribution that is capable of modeling drought duration and severity with different marginal distributions. Paramete...

Droughts can be characterized by their severity, frequency and duration, and areal extent. Depth-area-duration analysis, widely used to characterize precipitation extremes, provides a basis for evaluation of drought severity when storm depth is replaced by an appropriate measure of drought severity. We used gridded precipitation and temperature data to force a physically-based macroscale hydrol...

Different drought indices often provide different diagnoses of drought severity, making it difficult to determine the best way to evaluate these different drought monitoring results. Additionally, the ability of a newly proposed drought index, the Process-based Accumulated Drought Index (PADI) has not yet been tested in United States. In this study, we quantified the severity of 2012 drought wh...

There are two types of drought as conceptual drought and operational drought. The three parameters as the beginning, the end and the degree of severity of the drought can be identifying in operational drought by average precipitation in the whole region. One of the methods classified to measure drought is Reconnaissance Drought Index (RDI). Evapotranspiration is calculated using Penman-Monteith...

Drought is a complex phenomenon which can be characterised mainly by its severity, duration and areal extent. Among these three dimensions, drought severity is the key factor which can be used for drought analysis. Drought indices are typically used to assess drought severity in a meaningful way. DrinC (Drought Indices Calculator) is a software package which was developed for providing a simple...

This paper evaluates climate change effects on drought severity in the region of Thessaly, Greece. The Standardized Precipitation Index (SPI) has been used for estimation of drought severity. A geographical information system is applied for the division of Thessaly region to twelve hydrological homogeneous areas based on their geomorphology. Mean monthly precipitation values from 50 precipitati...

In recent years, global climate change has altered precipitation patterns, causing uneven spatial and temporal distribution of precipitation that gradually induces precipitation polarization phenomena. Taiwan is located in the subtropical climate zone, with distinct wet and dry seasons, which makes the polarization phenomenon more obvious; this has also led to a large difference between river f...