B. Ashraf; A. Alizadeh; M. Mousavi Baygi; M. Bannayan Awal
Abstract
Scince climatic models are the basic tools to study climate change and because of the multiplicity of these models, selecting the most appropriate model for the studying location is very considerable. In this research the temperature and precipitation simulated data by BCM2, CGCM3, CNRMCM3, MRICGCM2.3 ...
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Scince climatic models are the basic tools to study climate change and because of the multiplicity of these models, selecting the most appropriate model for the studying location is very considerable. In this research the temperature and precipitation simulated data by BCM2, CGCM3, CNRMCM3, MRICGCM2.3 and MIROC3 models are downscaled with proportional method according A1B, A2 and B1 emission scenarios for Torbat-heydariye, Sabzevar and Mashhad initially. Then using coefficient of determination (R2), index of agreement (D) and mean-square deviations (MSD), models were verified individually and as ensemble performance. The results showed that, based on individual performance and three emission scenarios, MRICGCM2.3 model in Torbat-heydariye and Mashhad and MIROC3.2 model in Sabzevar had the best performance in simulation of temperature and MIROC3.2, MRICGCM2.3 and CNRMCM3 models have provided the most accurate predictions for precipitation in Torbat-heydariye, Sabzevar and Mashahad respectively. Also simulated temperature by all models in Torbat-heydariye and Sabzevar base on B1 scenario and, in Mashhad based on A2 scenario had the lowest uncertainty. The most accuracy in modeling of precipitation was resulted based on A2 scenario in Torbat-heydariye and, B1 scenario in Sabzevar and Mashhad. Investigation of calculated statistics driven from ensemble performance of 5 selected models caused notable reduction of simulation error and thus increase the accuracy of predictions based on all emission scenarios generally. In this case, the best fitting of simulated and observed temperature data were achieved based on B1 scenario in Torbat-heydariye and Sabzevar and, A2 scenario in Mashhad. And the best fitting simulated and observed precipitation data were obtained based on A2 scenario in Torbat-heydariye and, B1 scenario in Sabzevar and Mashhad. According to the results of this research, before any climate change research it is necessary to select the optimum GCM model for the studying region to simulate climatic parameters.
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
M. Mousavi baygi; B. Ashraf
Abstract
Abstract
Nowadays, solar energy as one of the most important sources of clean and free of damaging environmental effects energy are used in many cases including generation of electricity, heat and desalination of salt water. The purpose of this research is identification of high radiation areas as most ...
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Abstract
Nowadays, solar energy as one of the most important sources of clean and free of damaging environmental effects energy are used in many cases including generation of electricity, heat and desalination of salt water. The purpose of this research is identification of high radiation areas as most suitable regions for these applications.To do this, cloudiness data of 120 synoptic stations were used to find the number of days with 0-2/8 cloudiness and calculate the average of monthly, seasonal and the annual of them over a period of 20 years (1989-2008). The statistical software of SPSS 16 was used to find the correlation equations of locations (latitude and altitude) with a mean seasonal (with R2 equal 0.81, 0.82 and 0.84 for spring, autumn and winter respectively) and annual number (with R2 equal 0.78) of days with low cloudiness. Finally by the method of interpolation Spline has been produced zoning maps of seasonal and annual high radiation areas of country. The investigation of average monthly amounts indicated that the most sunny days in April belonged to the BAFT, in May belonged to JASK, in June belonged MINAB, in July belonged to DEHLORAN, in August belonged MAHSHAHR, in September belonged BUSHEHR, in October belonged to KENARAK, in November and December belonged to CHABAHAR, in January and February belonged to SARAVAN and in March belonged to CHABAHAR. Also in seasonal scale the cities of KAHNUJ, AGHAJARI and CHABAHAR in spring, summer, and autumn & winter respectively were most high radiation regions of country during this period. The study also found that 89 stations of 120 stations that studied, over 1989- 2008 in more than 200 days of 365 days on the year (more than 55 percent on the year), had clear and sunny sky and therefore most areas of Iran have great ability to use renewable solar energy.
Keywords: Cloudiness, Solar radiation, Mapping, Spline interpolation method, Synoptic station
M. Mousavi Baygi; B. Ashraf; A. Nezami
Abstract
Abstract
Consistent decreasing and increasing of temperature in the short-term period that is called freezing and thaw cycles is one of the important factors of damage to crop productions. In this research as to determine freezing and thaw cycles in the Khorasan Razavi province, the data of daily minimum ...
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Abstract
Consistent decreasing and increasing of temperature in the short-term period that is called freezing and thaw cycles is one of the important factors of damage to crop productions. In this research as to determine freezing and thaw cycles in the Khorasan Razavi province, the data of daily minimum and maximum temperatures of 9 synoptic stations was used over 20 statistic years (1989-2008). Also 6 distinct range of temperatures including: the minimum temperatures lesser and equal whit -2 and the maximum temperatures greater and equal whit 2 (A), the minimum temperatures lesser and equal whit -3 and the maximum temperatures greater and equal whit 3 (B), the minimum temperatures lesser and equal whit -5 and the maximum temperatures greater and equal whit 5 (C), the minimum temperatures equal whit -2 and the maximum temperatures greater than 2 (D), the minimum temperatures equal whit -3 and the maximum temperatures greater than 3 (E) and the minimum temperatures equal whit -5 and the maximum temperatures greater than 5 were presented. After data processing by a computer program into the FORTRAN space, the number of days with this phenomenon for each station was determinated as monthly, seasonal and annual and then the mapping plans of susceptible areas were prepared. The results show that winter has a higher rate of this phenomenon and autumn and spring are next respectively. Also the investigation of mapping plans indicated that in most temperature ranges, the Torbat heydariye, Nishaboor and Ghuchan stations had maximum number of freezing and thaw cycles in Khorasan Razavi province. The minimum rate of this phenomenon was in the Sarakhs, Kashmar and Sabzevar Stations as well.
Keywords: Freezing and thaw cycles, Khorasan Razavi, Mapping, Maximum temperature, Minimum temperature
M. Mousavi Baygi; B. Ashraf
Abstract
Abstract
Drastic Precipitations in unmorally times always are one of the important factors that created abundant damages in different geographical areas. In this research, three Precipitations that occurred in summer 2009 in Mashhad were investigated. The investigation of variation graphs of meteorological ...
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Abstract
Drastic Precipitations in unmorally times always are one of the important factors that created abundant damages in different geographical areas. In this research, three Precipitations that occurred in summer 2009 in Mashhad were investigated. The investigation of variation graphs of meteorological parameters show significant decreasing of air pressure and temperature and increasing of relative humidity and dew point in days of occurrence precipitation compare with previous days. The result of physical analysis by using thephigram showed that existent of thick cloud whit noticeable perceptible water in sky of local in days of occurrence precipitation. Also situation of LCL and FCL levels and difference of height between top of cloud whit FCL and amount of dynamical indexes of CAPE, SHOW and KINX explains noticeable potential energy of ascendable air mass and suitable conditions for drastic instability of weather. For example amounts of dynamical indexes for torrent day (15 Sep) obtained 953.4, -4.67 and 35.30 respectively that are demonstrator of hard instability in this day. The investigation of surface isobars map showed contrast of tow Low and High pressure systems in east of country. Also 850 hpa isobars map indicate advection of warm weather from south to northeast that is similar whit surface pressure patterns. Therefore prove that developing of Siberian High pressure in warm season synchronic whit advection of warm and humid weather from south that caused drastic instability suddenly and this subject is supported physical analysis of vertical profile of atmosphere.
Keywords: Vertical profile, Summer rainfall, Advection of warm weather, Pressure systems, Physical and Dynamical indexes of atmosphere
M. Mousavi Baygi; B. Ashraf; A. Miyanabady
Abstract
چکیده
تابش خورشیدی رسیده به سطح زمین یکی از پرکاربردترین پارامترهای مورد استفاده در پروژه ها و مدل سازی های هیدرولوژی، کشاورزی، هواشناسی و اقلیمی می باشد. با توجه به ...
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چکیده
تابش خورشیدی رسیده به سطح زمین یکی از پرکاربردترین پارامترهای مورد استفاده در پروژه ها و مدل سازی های هیدرولوژی، کشاورزی، هواشناسی و اقلیمی می باشد. با توجه به این که تهیه و ایجاد وسایل اندازه گیری این پارامتر بسیار پرهزینه است، تاکنون مدل های متعددی جهت برآورد آن در اقلیم های مختلف توسط محققان، پیشنهاد شده است. در این پژوهش، هفت مدل برآورد تابش طول موج کوتاه خورشیدی، شامل: 1- مدل آنگستروم- پرسکات پیشنهادی توسط فائو، 2- مدل آنگستروم- پرسکات واسنجی شده توسط خلیلی و رضایی صدر، 3- مدل آنگستروم- پرسکات واسنجی شده توسط خلیلی و رضایی صدر تحت تأثیر طیف جذبی بخارآب، 4- مدل آنگستروم- پرسکات واسنجی شده توسط علیزاده و خلیلی، 5- مدل رگرسیون خطی علیزاده و خلیلی، 6- مدل صباغ و 7- مدل گلور- مک کلوت جهت انتخاب و معرفی مناسب ترین مدل در این منطقه مورد بررسی قرار گرفتند. نتایج مقایسه مقادیر محاسبه شده با مدل ها با مقادیر اندازه گیری شده توسط پیرانومتر، نشان داد که بر اساس میزان ضریب تعیین، مدل های 1، 2 و 4 (به ترتیب برابر 8505/0، 8507/0 و 8507/0) بیش ترین همبستگی را با مقادیر واقعی تابش، نشان می دهند. اما با توجه به تفاوت بسیار ناچیز این مدل ها و مقادیر کم تر شاخص های ، و (به ترتیب برابر 68/2، 16/0 و 59/0) در مدل 1، می توان این مدل را به عنوان مناسب ترین مدل برآورد تابش خورشیدی در این اقلیم معرفی نمود.
واژه های کلیدی: تابش طول موج کوتاه خورشیدی، پیرانومتر، طیف جذبی بخارآب، ضریب تعیین، اقلیم نیمه خشک
