Print Email Facebook Twitter Assessment of short- and long-term memory in trends of major climatic variables over Iran: 1966–2015 Title Assessment of short- and long-term memory in trends of major climatic variables over Iran: 1966–2015 Author Mianabadi, Ameneh (Ferdowsi University of Mashhad) Shirazi, Pooya (Ferdowsi University of Mashhad) Ghahraman, Bijan (Ferdowsi University of Mashhad) Coenders-Gerrits, Miriam (TU Delft Water Resources) Alizadeh, Amin (Ferdowsi University of Mashhad) Davary, Kamran (Ferdowsi University of Mashhad) Date 2018 Abstract In arid and semi-arid regions, water scarcity is the crucial issue for crop production. Identifying the spatial and temporal trends in aridity, especially during the crop-growing season, is important for farmers to manage their agricultural practices. This will become especially relevant when considering climate change projections. To reliably determine the actual trends, the influence of short- and long-term memory should be removed from the trend analysis. The objective of this study is to investigate the effect of short- and long-term memory on estimates of trends in two aridity indicators—the inverted De Martonne (ϕ IDM ) and Budyko (ϕ B ) indices. The analysis is done using precipitation and temperature data over Iran for a 50-year period (1966–2015) at three temporal scales: annual, wheat-growing season (October–June), and maize-growing season (May–November). For this purpose, the original and the modified Mann–Kendall tests (i.e., modified by three methods of trend free pre-whitening (TFPT), effective sample size (ESS), and long-term persistence (LTP)) are used to investigate the temporal trends in aridity indices, precipitation, and temperature by taking into account the effect of short- and long-term memory. Precipitation and temperature data were provided by the Islamic Republic of Iran Meteorological Organization (IRIMO). The temporal trend analysis showed that aridity increased from 1966 to 2015 at the annual and wheat-growing season scales, which is due to a decreasing trend in precipitation and an increasing trend in mean temperature at these two timescales. The trend in aridity indices was decreasing in the maize-growing season, since precipitation has an increasing trend for most parts of Iran in that season. The increasing trend in aridity indices is significant in Western Iran, which can be related to the significantly more negative trend in precipitation in the West. This increasing trend in aridity could result in an increasing crop water requirement and a significant reduction in the crop production and water use efficiency. Furthermore, the modified Mann–Kendall tests indicated that unlike temperature series, precipitation, ϕ IDM , and ϕ B series are not affected by short- and long-term memory. Our results can help decision makers and water resource managers to adopt appropriate policy strategies for sustainable development in the field of irrigated agriculture and water resources management. To reference this document use: http://resolver.tudelft.nl/uuid:9b3b50e2-de21-4f2b-ae65-249db76eab7b DOI https://doi.org/10.1007/s00704-018-2410-z Embargo date 2019-02-01 ISSN 1434-4483 Source Theoretical and Applied Climatology Part of collection Institutional Repository Document type journal article Rights © 2018 Ameneh Mianabadi, Pooya Shirazi, Bijan Ghahraman, Miriam Coenders-Gerrits, Amin Alizadeh, Kamran Davary Files PDF Mianabadi_et_al_Manuscrip ... sed_1_.pdf 5.68 MB Close viewer /islandora/object/uuid:9b3b50e2-de21-4f2b-ae65-249db76eab7b/datastream/OBJ/view