Atmospheric drought in lowlands in Slovakia is analyzed on the bases of Standardised Precipitation Index (SPI) and Standardised Precipitation Evapotranspiration Index (SPEI). This paper gives information about the dynamic, intensity, seasonal and territorial differences in occurrence of drought with various intensity: mild (near to normal), moderate, severe and extreme for the period 1961–2011....

This study evaluates drought at Lashkargah, Farah, Adraskan, and Gardandiwal stations in Helmand River Basin (HRB) Afghanistan to determine appropriate indices for the basin. Thirty seven years of monthly recorded precipitation data from 1979 2015 are employed with different index (DI) methods which include Standardized Precipitation Index (Normal-SPI, Log-SPI, Gamma-SPI), Percent Normal (PN), ...

Abstract The Standard Precipitation Index (SPI) is a widely used statistical technique for the characterization of droughts. It based on probabilistic standardization procedure, which converts Gamma-type probability distribution function (PDF) into normal (Gaussian) standard series with zero mean and unit deviation. Drought classification SPI indicates dry wet spell characteristics, provided th...

Drought plays a crucial role in agriculture, especially farming and has significant impact on the environment. The present study focuses forecast of drought using one hybrid artificial neural network namely Adaptive NeuroFuzzy Inference System (ANFIS). For this study, 39 years monthly precipitation value Erode district are used. Firstly, values, Standard Precipitation Index (SPI) values compute...

The common versions (referred to as self-calibrated here) of the Standardized Precipitation Index (SPI) and the Palmer Drought Severity Index (PDSI) are calibrated and then applied to the same weather series. Therefore, the distribution of the index values is about the same for any weather series. We introduce here the relative SPI and PDSI, abbreviated as rSPI and rPDSI. These are calibrated u...

Drought analysis via the Standardized Precipitation Index (SPI) and Evapotranspiration (SPEI) is necessary for effective water resource management in Sarawak, Malaysia. Rainfall best indicator of a drought, but temperature also significant because it controls evaporation condensation. This study examined drought periods state Sarawak using SPI SPEI based on monthly precipitation data from thirt...