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DROUGHT INDEX FREQUENCY ANALYSIS USING L-MOMENTS
Where: “Managing water in a changing world” - Torino (Italy), Commission on Water Sustainability - IGU Dates: 27th July 2009 - 31st July 2009
Sayed Saeid ESLAMIAN, Hadi HASANZADEH, Jahangir ABEDI-KOUPAI
Drought is a normal and recurrent climatic feature that occurs in virtually every climatic zone around the world, causing billions of dollars in loss annually for the farming community. According to the previous studies, drought has the first rank among all natural hazards. This is because, compared to other natural hazards like floods and hurricanes that develop quickly and end in a short time, drought is a creeping phenomenon that accumulates over a period of time across a vast area, and the effect lingers for years even after the end of drought.
For evaluating the severity of drought of a certain year, the maximum cumulative difference between potential evapotranspiration and precipitation is used such that a regional frequency analysis has been carried out by L-moments. This measure of drought is strongly related to moisture deficits for the vegetation during the growing season.
In this paper, 11 synoptic stations in Isfahan province, Iran with a semi-arid environment have been used that those have minimum 10 years data and the mentioned index drought calculated for all of them. FAO Penman-Monteith is used for calculating potential evapotranspiration that according to the previous studies, this method is suitable for this region. Hosking homogeneity test is applied for identifying a homogeneous region with distinguishing and omitting Naeen station as an outlier station. So for the 10 remaining stations, Hosking goodness of fit test is performed. Two Parameter Lognormal (LN2) is selected as the best regional distribution.
The results show that, Ardestan, Shargh Isfahan and Shahreza stations have the most severity drought and
the drought indices for these stations for 100-year return period are 2060.6, 1576.9 and 1550.5 mm, respectively and for 200-year return period are 2112.4, 1616.5 and 1589.5 mm, respectively.
Using the results of this research, required water volume for agriculture can be determined in this province.
LikeClimate Change Impact on Frequency Analysis of Wind Speed
Where: MOCA-09 , Montreal, Canada Dates: 19th July 2009 - 29th July 2009
S. Eslamian, H. Hasanzade
The enhanced greenhouse gas effect is expected to cause high temperature increase globally (1–3.5 0C) and this will lead to an increase in precipitation in some regions while other regions will experience a reduced precipitation (±20%). The impact of expected climate change will affect almost all the sectors of the human endeavor. The purpose of this study is, to detect an existing trend in wind speed and an evaluating effect of climate change on frequency analysis in Iran.
Twenty two stations that their length of records is higher than fifty years have been selected. Five statistical methods are used to detect the trends that are Mann-Kendall, Spearman, Cumulative deviation, Autocorrelation coefficient and Regression analysis. It is revealed clear that eleven stations have an increase or an decrease in trend and the rest has no trend. Climate change leads to being no homogeneity in number of the stations that therefore, it is impossible for using frequency analysis for those stations. One appropriate approach is dividing the stations into two smaller parts, and for each part frequency analysis could be taken if that part is homogenous.
Effects of variations in climate parameters on evapotranspiration in the arid and semiarid
Where: Lund University, Sweden Dates: 3rd May 2009 - 8th May 2009
Saeid Eslamian, Mohammad Javad Khordadi, Arezou Baba Ahmadi and Jahangir Abedi
The main objective of this study is to investigate the effects of climatic parameters variability on evapotranspiration in five climatologically different regions of Iran. The regions include Tehran, Esfahan, Shiraz, Tabriz and Mashhad. Fifty four-year monthly records of temperature, relative humidity, sunshine duration, wind speed, and precipitation depth from 1951 to 2005 comprise the database. Trend and persistence analyses of the data are performed using the Mann–Kendall test, the Cumulative Deviation test, Linear Regression, and the Autocorrelation Coefficient. A sensitivity analysis of meteorological variables in these five regions is carried out using Penman-Monteith formula. In all of studied regions, temperature and relative humidity are the most sensitive parameters in Penman-Monteith formula respectively. The results of this study indicate that the effective climatic variables in evapotranspiration are changing, though in each region the variables have significant long-term trends and persistence.
Detection of Hydrologic Changes
Where: International Symposium on Drylands Ecology and Human Security: Perspectives, Policy Responses and Sustainable Development, Gcc Network For Drylands Research And Development Dates: 4th December 2006 - 7th December 2006
United Arab Emirates, Dubai.
Runoff in an Iranian Karstic Watershed as Compared with a Neighbor non-Karstic Watershed
Where: 8th Conference on Limestone Hydrogeology, IGCP Project No.513:Global Study of Karst Aquifers and Water Resources: 2005-2009 Dates: September 2006 - September 2006
Neuchâtel, Switzerland)
Where: Annual International Conference on Soil, Sediments, Water, Energy, University of Massachusetts Dates: 17th October 2005 - 20th October 2005
A. Goudarzi, S. S. Eslamian and R. Nazari
In recent decades, with continuous droughts, demand for water has been increased and per capita renewable-water has been decreased in many countries which are faced with water limitation and scarcity. Considering the particular hydrologic conditions in Iran, seasonal floods and high intensity of rainfall are important and using artificial recharge projects is unavoidable to augment the water resources. The major problem with recharging projects is the entrance of sediments to the recharging basins. Due to depositing the floating particles, it is necessary to treat and recover permeability of the basins. In this paper, we compare permeability of the basins for artificial recharge in Bagh-e-Sorkh region of Isfahan. To measure the permeability, four double rings have been installed in different places for each basin’s bed and the permeability was measured. Also, some samples were taken from sediments of the region and some of their physical and chemical characteristics, such as soil texture, EC, and nourishing elements, were measured. The results showed that permeability for beds of the pounds highly decreased and had fallen to less than 10 (the first basin) to 25 percent (the fifth basin) of the initial value. Comparing the physical characteristics of sediments from the different pounds indicates that with increasing distance from the system starting point, the sediment depth is decreased and on the contrary the fine sediments are increased. Because of this, the sediment’s thickness was not so much influential in amount and the pace of the final permeability.
Evaporation Modeling For Some Dam Reservoirs in Iran
Where: 2004 Western Pacific Geophysical Meeting, American Geophysic Union (AGU) Dates: 16th August 2004 - 20th August 2004
Hawaii, USA
Optimization and Simulation of Water Distribution in Small Multi-Reservoir
Where: The Sixth International Conference on Hydro-science and Engineering, National Center for Computational Hydroscience and Engineering Dates: 30th May 2004 - 3rd June 2004
Brisbane, Australia.
Water resources mismanagement and desertification of a semiarid region: Gavahan Plain
Where: Seventh International Dryland Development Conference, INTERNATIONAL CENTER FOR AGRICULTURAL RESEARCH IN THE DRY AREAS Dates: 14th September 2003 - 17th September 2005
Tehran
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