B. Ashraf; M. Mousavi Baygi; Gh.A. Kamali; K. Davary
Abstract
Abstract
The most important part of the design and operation of the supplier systems of agricultural water requirement is the estimating of plant water requirement. In this study by using the LARS-WG5 model, downscaled the data of HADCM3 model according A1B, A2 and B1 scenarios that confirmed by IPCC, ...
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Abstract
The most important part of the design and operation of the supplier systems of agricultural water requirement is the estimating of plant water requirement. In this study by using the LARS-WG5 model, downscaled the data of HADCM3 model according A1B, A2 and B1 scenarios that confirmed by IPCC, and was simulated monthly amounts of precipitation, minimum temperature, maximum temperature and sunshine hours in Khorasan Razavi province in the period 2011 - 2030. Then using OPTIWAT software, reference evapotranspiration and effective rainfall calculated with Hargreaves- Samani and FAO method respectively and finally the water requirement of sugar beet was estimated in monthly scale for the two next decades compared with the base period (1991-2010). The results showed that spring and autumn precipitation in the future period will be increased in all stations except Torbat Jam compared with the base period. Most increase of precipitation equal 26, 21 and 16 percent based in A1B, A2 and B1 scenarios compared with the base period is owned Mashhad Station and will occur in April. Also according simulation of LARS-WG5 model, Minimum and maximum temperatures will increase during 2011 to 2030 and the increase of the minimum temperature is more than maximum temperature. As a result of these changes, the water requirement of sugar beet in 20 next years in most of the city of Khorasan Razavi province will be different compared to the current period. So that the Torbat Jam station under scenario A1B, A2 and B1, respectively 19, 18 and 18 percent and in the Golmakan respectively 15, 17 and 17 percent, water requirement of this plant will increase from the period of development until the beginning of the final period of growth and in Ghuchan, Nishabur and Mashhad will decrease in the middle period of growth. The most amounts of the reducing in water requirement equal 10 percent and belonging to Ghchan station. The results of running OPTIWAT software also showed that in Sarakhs, Gonabad, Kashmar and Sabzevar, would not happen perceptible change in the amount of water requirement of this plant in the next two decades compared with the base period,.
Keywords: Downscaling, Climate change scenarios, HADCM3 model, OPTIWAT software, Water requirement
B. Ashraf; M. Mousavi Baygi; G.A. Kamali; K. Davari
Abstract
Abstract
Due to low spatial resolution or simplifying of some micrometeorological phenomena, atmospheric general circulation models are not able to give a good estimation for weather conditions over study area. So their outputs should downscale into weather stations scales. In this research data of ...
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Abstract
Due to low spatial resolution or simplifying of some micrometeorological phenomena, atmospheric general circulation models are not able to give a good estimation for weather conditions over study area. So their outputs should downscale into weather stations scales. In this research data of HADCM3 downscaled by using LARS-WG5 with three scenarios, confirmed by IPCC including A1B, A2 and B1 and seasonal variations of precipitation, min temperature, max temperature and sunshine hours of Khorasan Razavi province were investigated over 2011- 2030. Results show that the amount of precipitation in all stations will increase in autumn, winter and spring except Torbat-jam. Also the amount of precipitation in Kashmar during the autumn will decrease. The maximum and minimum increases in precipitation are belonging to Ghoochan and Sarakhs respectively. The results also show that the minimum temperature in all seasons and under three scenarios indicate rising trend in most cities. The only exception in this case occurred in autumn for Sarakhs based on A1B scenario. About maximum temperature and sunshine hours, although three scenario would not explain the same pattern, but generally in the next 20 years, the maximum temperature of Khorasan Razavi province, will increase and sunshine hours will decrease. Also despite the variation of maximum temperature is less than minimum temperature, is expected increase of average air temperature in this period. So according to these results, climatic conditions of Khorasan Razavi province in the next 20 years will have noticeable different with the present conditions and seems necessary, long-term and strategic planning to manage this situation.
Keywords: Climate change, Downscaling, General circulation model, LARS-WG5 model
Gh.A. Kamali; P. Mollaei; M.B. Behyar
Abstract
Abstract
The goal of this survey is to prepare the dry land wheat atlas for Zanjan province, according to the climate data. So we can recognize which areas are susceptible and to understand climate capabilities and limitations for dry land wheat. For reaching this purpose first raining and temperature ...
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Abstract
The goal of this survey is to prepare the dry land wheat atlas for Zanjan province, according to the climate data. So we can recognize which areas are susceptible and to understand climate capabilities and limitations for dry land wheat. For reaching this purpose first raining and temperature datas of the research region were gathered and analyzed. At the first stage, proper according to the first rain after Mehr which should have continued for 1 or 2 days and rained 5mm or more planting date was defined. Then the different levels of dry planting wheat's growth was calculated by the GDD method. At the next stage the annual , autumn, spring and Khordad's rainfall were reviewed and the average was calculated. The probability of germination temperatures, maximum temperature 25 and 30 degrees centigrade in the flowering stage and grain filling stage was also calculated. The calculated quantities in the GIS system were converted into different arenas and by using the overlap method all layers were first given a weighing value and were incorporated afterwards. Finally Zanjan Provinces Dry Land Wheat Atlas area with 4zones: very good, good, average and poor was prepared. As you can see in the map the most suitable regions for dry land wheat are in the center and north of Khodabandeh and east of Ijrood and of coarse the other parts of Zanjan province are suitable. At the end the product producing scale is calculated and according to the neighbor provinces turnover scale which have the same weather and a higher turnover, the medium turnover and producing scale for Zanjan was calculated which showed a 30% increase from the real production rate.
Keywords: Atlas, DryLand Wheat, GIS, GDD, Planting date
Z. Toufaninezhad; Gh.A. Kamali; A. Alizadeh
Abstract
Abstract
Obtaining reliable precipitation observations is important for hydrological simulations and weather forecasting. Radar data can provide insight in the spatial variation of precipitation and can also detect large areas of rain and estimate rainfall rates. Weather radar systems nearly always ...
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Abstract
Obtaining reliable precipitation observations is important for hydrological simulations and weather forecasting. Radar data can provide insight in the spatial variation of precipitation and can also detect large areas of rain and estimate rainfall rates. Weather radar systems nearly always operate in S-, C- or X-band. Since X-band systems require smaller antennas than those at C- or S- band, they are particularly suitable for monitoring small hydrological working. However, radar rainfall estimation can be prone to errors because of attenuation and ground clutter. In this study, the potential of X-band radar systems for rainfall estimation over an urban area in the Netherlands was discussed. A methodology was presented for removing ground clutter and attenuation from X-band radar measurements and finally measurements of rainfall from radar were compared against measurements from 4 tipping bucket rain gauges for a rainfall event. In general, the analysis demonstrated that the radar follows the general trend of the rain gauge measurements but the radar measurements need to be calibrated and corrected for errors.
Key word: Ground base radar, Ground clutter, Attenuation, Rainfall estimation
Gh.A. Kamali; A. Sedghiani; A. Sedaghat kerdar
Abstract
Abstract
Since the majority of dryland farming area in eastern Azerbaijan is devoted to wheat production, therefore, climate zoning of dryland wheat was set as the goal of this research. For this reason long term climatic data of 39 meteorological stations inside the province and 7 synoptic stations ...
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Abstract
Since the majority of dryland farming area in eastern Azerbaijan is devoted to wheat production, therefore, climate zoning of dryland wheat was set as the goal of this research. For this reason long term climatic data of 39 meteorological stations inside the province and 7 synoptic stations out of the province were used. The most proper planting date was suggested based on the commencement of rainy season in each part of the province, and the different growth stages of dryland wheat were determined. Using the precipitation data, the climatic isohyetal maps of the following were derived: annual rain, rain during germination, rain during flowering, and rain during seed filling stage. In addition, using temperature data the climatic isothermal maps for germination, thermal stress during flowering and seed filling stages were developed for the province. Finally, these maps were compiled in GIS and afterward the climatic zoning of dryland wheat was derived. The areas with no potential of wheat dryland farming were omitted. The final map showed the most appropriate, appropriate, medium, and poor climatic zoning. The zoning in the map indicated that areas in the north part of the province had the most appropriate climatic conditions for dryland farming. The concentration of medium to poor climatic zoning was located in a strip which was stretched from east to west part of the province.
Key words: Climatic Potentila, Rain – fedeheat, East Azarbaijan
M. Vazifedoust; A. Alizadeh; Gh.A. Kamali; M. Feyzi
Abstract
Abstract
To explore the on-farm strategies which result in higher economic gains and water productivity (WP), a physically based agro-hydrological model, Soil Water Atmosphere Plant (SWAP), was calibrated and validated using intensive measured data at 8 selected farmer fields (wheat, fodder maize, sunflower ...
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Abstract
To explore the on-farm strategies which result in higher economic gains and water productivity (WP), a physically based agro-hydrological model, Soil Water Atmosphere Plant (SWAP), was calibrated and validated using intensive measured data at 8 selected farmer fields (wheat, fodder maize, sunflower and sugar beet) in the Borkhar district, Isfahan during the growing seasons of 2004-05. The WP values for the main crops were computed using the SWAP simulated water balance components i.e. transpiration (T), evapotranspiration (ET), irrigation (I), and the marketable yield (Y)M in terms of YM T -1, YM ET -1 and YM I -1. The average WP, expressed as YM T -1 (kg m-3) was 1.18 for wheat, 3.38 for fodder maize, 0.33 for sunflower and 1.72 for sugar beet. This indicated that fodder maize provided the highest economic benefit in the Borkhar irrigation district. Soil evaporation caused the average WP values, expressed as YM ET-1 (kg m-3), to be at least 11 to 27% lower than the average WP, expressed as YM T-1. Furthermore, due to percolation from root zone and stored moisture content in the root zone, the average WP values expressed as YM I-1 (kg m-3), had a 24 to 42 % reduction as compared with WP expressed as YM ET-1. Improved irrigation practices in terms of irrigation timing and amount, increased WP in terms of YM I-1 (kg m-3) by a factor of 1.5 for wheat and maize, 1.3 for sunflower and 1.1 for sugar beet.
Key words: Water productivity, Irrigation practices, Wheat, Fodder maize, Sunflower, Sugar beet
