Titill: | Decadal Spatial-Temporal Variations in the Spatial Pattern of Anomalies of Extreme Precipitation Thresholds (Case Study: Northwest Iran) |
Höfundur: |
|
Útgáfa: | 2017-08-03 |
Tungumál: | Enska |
Umfang: | 135 |
Háskóli/Stofnun: | Háskóli Íslands University of Iceland |
Svið: | Verkfræði- og náttúruvísindasvið (HÍ) School of Engineering and Natural Sciences (UI) |
Deild: | Raunvísindadeild (HÍ) Faculty of Physical Sciences (UI) |
Birtist í: | Atmosphere;8(8) |
ISSN: | 2073-4433 |
DOI: | 10.3390/atmos8080135 |
Efnisorð: | Extreme precipitation threshold; Anomaly; Weighted mean center; Gi; Harmonic analysis; Iran; Veðurfarsrannsóknir; Veðurfarsbreytingar; Loftslagsrannsóknir |
URI: | https://hdl.handle.net/20.500.11815/426 |
Tilvitnun:Rousta, I.; Nasserzadeh, M.H.; Jalali, M.; Haghighi, E.; Ólafsson, H.; Ashrafi, S.; Doostkamian, M.; Ghasemi, A. Decadal Spatial-Temporal Variations in the Spatial Pattern of Anomalies of Extreme Precipitation Thresholds (Case Study: Northwest Iran). Atmosphere 2017, 8, 135. doi:10.3390/atmos8080135
|
|
Útdráttur:This study focused on decadalvariations of extreme precipitation thresholds within a 50-year period (1961–2010) for 250 stations of Iran’s northwest. The 99th percentile was used as the threshold of extreme precipitation. In order to analyze threshold cycles and spatial autocorrelation pattern dominating extreme precipitation thresholds, spectral analysis and Gi (known as HOTSPOT) were used respectively. The results revealed that the highest threshold of extreme precipitation occurred along the Ghoosheh Dagh mountain range. Additionally, in all the five studied decades, the highest positive anomalies were observed in the same region (i.e., the Ghoosheh Dagh). The findings also showed that the intensity of positive spatial autocorrelation pattern of extreme precipitation thresholds experienced a declining trend in recent decades. At the same time, extreme precipitation weighted mean center indicated that they followed an ordered pattern during the studied period. The results of harmonic analysis demonstrated that, in all decades, short-term (2–4 years) and mid-term (4–8 years) cycles of extreme precipitation thresholds were dominated. However, especially the southwest of the studied area, the return period of extreme precipitation thresholds was as long as the studied period, a phenomenon that indicates the existence of a trend in extreme precipitation thresholds of these regions.
|
|
Leyfi:This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).
|