TY  - JOUR
A1  - Shahabfar, Alireza
A1  - Eitzinger, Josef
T1  - Spatio-Temporal Analysis of Droughts in Semi-Arid Regions by Using Meteorological Drought Indices
JF  - Atmosphere
N2  - Six meteorological drought indices including percent of normal (PN), standardized precipitation index (SPI), China-Z index (CZI), modified CZI (MCZI), Z-Score (Z), the aridity index of E. de Martonne (I) are compared and evaluated for assessing spatio-temporal dynamics of droughts in six climatic regions in Iran. Results indicated that by consideration of the advantages and disadvantages of the mentioned drought predictors in Iran, the Z-Score, CZI and MCZI could be used as a good meteorological drought predictor. Depending on the month, the length of drought and climatic conditions of the region, they are an alternative to the SPI that has limitations both because of only a few available long term data series in Iran and its complex structure.
KW  - semi-arid region
KW  - standardized precipitation index
KW  - drought index
KW  - drought monitoring
KW  - Iran
Y1  - 2013
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-128644
VL  - 4
IS  - 2
ER  - 
TY  - JOUR
A1  - Ullmann, Tobias
A1  - Büdel, Christian
A1  - Baumhauer, Roland
A1  - Padashi, Majid
T1  - Sentinel-1 SAR Data Revealing Fluvial Morphodynamics in Damghan (Iran): Amplitude and Coherence Change Detection
JF  - International Journal of Earth Science and Geophysics
N2  - The Sentinel-1 Satellite (S-1) of ESA's Copernicus Mission delivers freely available C-Band Synthetic Aperture Radar (SAR) data that are suited for interferometric applications (InSAR). The high geometric resolution of less than fifteen meter and the large coverage offered by the Interferometric Wide Swath mode (IW) point to new perspectives on the comprehension and understanding of surface changes, the quantification and monitoring of dynamic processes, especially in arid regions. The contribution shows the application of S-1 intensities and InSAR coherences in time series analysis for the delineation of changes related to fluvial morphodynamics in Damghan, Iran. The investigations were carried out for the period from April to October 2015 and exhibit the potential of the S-1 data for the identification of surface disturbances, mass movements and fluvial channel activity in the surroundings of the Damghan Playa. The Amplitude Change Detection highlighted extensive material movement and accumulation - up to sizes of more than 4,000 m in width - in the east of the Playa via changes in intensity. Further, the Coherence Change Detection technique was capable to indicate small-scale channel activity of the drainage system that was neither recognizable in the S-1 intensity nor the multispectral Landsat-8 data. The run off caused a decorrelation of the SAR signals and a drop in coherence. Seen from a morphodynamic point of view, the results indicated a highly dynamic system and complex tempo-spatial patterns were observed that will be subject of future analysis. Additionally, the study revealed the necessity to collect independent reference data on fluvial activity in order to train and adjust the change detector.
KW  - SAR
KW  - InSAR
KW  - coherence
KW  - Iran
KW  - Sentinel-1
KW  - radar
KW  - geomorphology
KW  - change detection
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-147863
VL  - 2
IS  - 1
ER  - 
TY  - JOUR
A1  - Wilhelm, Gernot
T1  - Ist das Elamische eine Ergativsprache?
N2  - No abstract available
KW  - Iran
KW  - Archäologie
Y1  - 1978
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-82762
ER  -