چکیده:
Drought detecting is a necessary aspect of drought risk management. It is generally performed using different drought indices that are effectively continuous functions of rainfall and other hydro- meteorological variables. A number of drought indices have been introduced and used in various countries to date. In the current research, four meteorological drought indices including the standardized precipitation index (SPI), China-Z index (CZI), modified CZI (MCZI) and Z-Score (Z) are compared and evaluated for monitoring droughts in Salt Lake Basin in Iran. The comparison of indices was carried out based on drought classes that were monitored in the study area using 40 years of data. The results indicated that SPI, CZI and Z-Score performed similarly with regard to drought identification and responded slowly to drought onset. DI appeared to be very sensitive to precipitation rates, but had unsteady spatial and temporal variation. Additionally, by considering the advantages and disadvantages of the mentioned drought predictors in Iran, the CZI and ZScore could be used as good meteorological drought predictors.
خلاصه ماشینی:
"ir Desert 19-2 (2014) 155-165 Meteorological drought monitoring using several drought indices (case study: Salt Lake Basin in Iran) B.
In the current research, four meteorological drought indices including the standardized precipitation index (SPI), China-Z index (CZI), modified CZI (MCZI) and Z-Score (Z) are compared and evaluated for monitoring droughts in Salt Lake Basin in Iran.
(2006) studied drought conditions by comparing seven drought indices (decile index, percentage of normal index, standardized precipitation index (SPI), China-Z index (CZI), modified CZI, Z-score and effective drought index (EDI)) in Tehran Province, Iran.
Bazrafshan (2002) analysed seven meteorological drought indices for diverse climates in Iran (arid to very humid regions) and recommended SIAP, SPI and EDI for drought monitoring on annual, monthly, and daily timescales, respectively.
In this regard, the purpose of this article was to compare the performance and assess the capability of several rainfall-based drought indices for Salt Lake Basin in Iran.
Methodology In order to contribute to improved drought monitoring in Salt Lake Basin in Iran, in this study, seven drought indices were selected including a decile index (DI), standardized precipitation index (SPI), China-Z index (CZI), modified CZI (MCZI) and Z-Score (Z) for use in multiple time scales in six climate regions.
Conclusion This study focused on the application of four known drought indices (CZI, MCZI, Z-score, SPI and DI) for drought detection and monitoring in Salt Lake Basin in Iran.
Instead of the SPI, these indices can be applied for operational use that is limited by the availability of long-term climatic data and low sensitivity to agro-meteorological drought conditions (Shahabifar and Eitzinger, 2013)."