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1 Joural of Ragelad Sciece, 2013, Vol. 3, No. 3 Saadatfar et al. / 265 Cotets available at ISC ad SID Joural homepage: Full Legth Article: Statistical Dowscalig HadCM3 Model for Detectio ad Perdictio of Seasoal Climatic Variatios (Case Study: Khabr Ragelad, Kerma, Ira) Amir Saadatfar A, Hossei Barai B, Abdol Reza Bahremad C, Ali Reza Massah Bavai D, Adel Sepehry E, Ahmad Abedi Servestai F A Ph.D Studet, Dep. of Rage Lad Maagemet, Agricultural Scieces & Natural Resources Uiversity of Gorga. (Correspodig Author). amir_saadat0045@yahoo.com. B Assistat Professor, Dep. of Rage Lad Maagemet, Agricultural Scieces & Natural Resources Uiversity of Gorga. C Assistat Professor, Dep. of Watershed ad Arid Zoe Maagemet, Agricultural Scieces & Natural Resources Uiversity of Gorga. D Assistat Professor, Irrigatio Group, Abureyha Uiversity, Tehra. E Professor, Dep. of Rage Lad Maagemet, Agricultural Scieces & Natural Resources Uiversity of Gorga. F Assistat Professor, Dep. of Agricultural Exyesio ad Educatio, Agricultural Scieces & Natural Resources Uiversity of Gorga. Received o: 14/08/2013 Accepted o: 05/01/2014 Abstract. Ragelads are oe of the most vulerable parts cocerig the climate chages impacts. These impacts are eve stroger i the arid ad semi-arid areas where ragelad ecosystems are i critical coditios. Therefore, it is crucial to figure out the actual dyamics of climate variatios o the ragelads. The aim of this research was to determie climate chages i Khabr ragelad, Kerma, Ira. So, four meteorological data sets of HadCM3 model icludig miimum ad maximum temperature, precipitatio ad radiatio rates were used to assess climate chages i the regio. I this regard, climate chages durig were assessed by dowscalig HadCM3 data usig LARS-WG model uder three scearios of B1, A2 ad A1B. The results have showed that the raifall rates of sprig ad summer would have decliig treds uder all three scearios. Miimum ad maximum temperature rates would icrease i all seasos, ad just radiatio oe showed a decreasig tred for witer. Based o A1B sceario, miimum ad maximum temperature rates had the highest icreasig tred. Radiatio ad precipitatio had the highest icreasig ad decliig treds i the A2 sceario, respectively. Moreover, the icrease i maximum ad miimum temperature rates was averagely greater tha the past ad cosequetly despite the icreasig tred i miimum ad maximum temperature rates, the icrease i the mea temperature rate durig this period would be expected. Accordig to the results, Khabr ragelad s climatic coditios will be sigificatly differet i the ext 30 years ad log-term ad strategic plaig is ecessary i cosistet with the maagemet policies with these coditios. Key words: Climatic-Parameters, HadCM3, LARS-WG, Khabr ragelads

2 J. of Rage. Sci., 2013, Vol. 3, No. 3 Statistical / Itroductio Climatic chages are ascribed to huma activities that chage the structure of the global atmosphere ad to atural climate variability observed over comparable time periods (IPCC, 2007). Huma activities, particularly the burig of fossil fuels ad chages i lad uses are today believed to icrease the atmospheric accumulatio of greehouse gases. This chage of eergy balace has led to make the atmosphere warm ad cosequetly, climatic chages. Some researches show that climatic parameters such as mea aual global surface temperature have icreased by about o C sice the late 19th cetury, ad it is aticipated to icrease by º C over the ext 100 years (Solomo et al., 2007). The most importat impacts of climatic chages o ragelads will probably chage both pasture productivity ad forage quality. However, there are other impacts o ragelads that maagers will cofrot icludig botaical chages i vegetatio compositio, pests, diseases, soil erosio, aimal husbadry ad health (Hall et al., 1998). Curretly, global climate models are the oly reliable tools available for simulatig the respose of the uiversal climate system to the icrease of greehouse-gas cocetratios (IPCC- TGCIA, 2007). Therefore, the fourth assessmet report of AR4 was costructed accordig to a huge dataset about forthcomig climate-chage projects by 18 worldwide groups, ad climate experieces were ru i several Global Climate Models (GCMs), ad differet scearios (Semeov, 2008; Semeov ad Stratoovitch, 2010). Scietists emphasize the eeds for appropriate model testig agaist the observed data ad the evaluatio of ucertaity i future projectios. Furthermore, climate models fuctios at spatial scales are cosiderably larger tha those i which maagerial decisios are made o the desired ecosystems. Dowscalig allows data obtaied from global ad regioal models to be estimated for fier spatial scales. There is therefore a eed to utilize the existig methods or develop ew oes as appropriate oes from dowscale climate model estimates to scales that are more relevat for site-specific decisiomakig. By the help of dowscalig method, the GCM outputs ca be correctly chaged ito surface variables i the scale of the basi uder study. This method is based o the statistical model likig the climate simulated by the GCM, ad the curret climate characterized by istrumetal data. This method has bee widely applied to derive the daily ad mothly precipitatio rates at higher spatial resolutios for the impact assessmets (Semeov ad Barrow, 2002; Wilby et al., 2002). LARS-WG stochastic weather geerator simulates high-resolutio temporal (daily) ad spatial (site) climatic chages scearios for a umber of climate variables (e.g. precipitatio, maximum/miimum temperature, ad solar radiatio rates). Scearios have combied the chages with climatic variables such as duratio of dry ad wet spells or temperature variability derived from the daily output from GCMs (Semeov ad Barrow, 2002). Future climate scearios are stochastically geerated by adjustig the parameters with respect to the directios proportio to the chages projected by a GCM. Further details of the LARS-WG ca be foud i the user maual (Semeov ad Barrow, 2002). The mai advatage of weather geerators is their ability to geerate multiple climate scearios of daily climatic variables at a local statio while makig them very useful for the risk assessmet studies. Therefore, they will be used withi this study for the maufacturig of future climatic scearios. The aim of this research was to determie climatic chage i Khabr ragelad, Kerma, Ira. So, four

3 Joural of Ragelad Sciece, 2013, Vol. 3, No. 3 Saadatfar et al. / 267 meteorological datasets of HadCM3 model icludig miimum ad maximum temperature, precipitatio ad radiatio rates were used to assess climatic chage i the regio. 2. Materials ad Methods The field research is a part of Khabr Natioal Park s ragelads located i Kerma Provice i the south-east of Ira (29º 14' N, 56º 35' W, see Fig. 1). Accordig to Emberger method, the regio climate is arid frigid. The study site receives about 261 mm of aual precipitatio that mostly occurs durig November ad May. The aual mea temperature is 17.6 ºC. Accordig to gausse ambrothermic diagram, the regio aridity period is 7 moths. Low precipitatio ad high vapourtraspiratio i this area have led to a severe drought i the recet decades. Fig. 1. Locatio of case study, Khabr- Baft Selectio of best weather statio with sufficiet data Simulatio of climatic parameters with LARS-WG Preparatio of daily-scale climatic parameters Compariso of actual ad simulatio data Evaluatio of model performace Model Calibratio Model Validatio Geeratio of Sythetic Weather Data Fig. 2. Research method diagram

4 J. of Rage. Sci., 2013, Vol. 3, No. 3 Statistical / Case study I this study, four mai sources of data were used which are as follow: 1- Daily historical temperature ad precipitatio data of Baft meteorological statio durig (miimum temperature (T-mi), maximum temperature (T-max), precipitatio (P) ad sushie hours). 2- Daily projected data of HadCM3 durig (T-mi, T-max ad P ad sushiy hours) that were resulted from GCM-rus for the Third Assessmet Report (TAR) based o the IPCC-SRES sceario of A2. 3- Mothly projected data of HadCM3 durig (T-mi, T-max, P ad suy hours) based o the sceario of B1. 4- Mothly projected data of HadCM3 durig (T-mi, T-max, P ad suy hours) based o the sceario of A1B. As it has bee show i the research method diagram (see Fig. 2), LARS-WG model was applied to simulate climatic parameters. This model is oe of the weather geerators which ca be utilized for the simulatio of weather data at a sigle site (Rasco et al., 1991) uder curret ad future climatic coditios. These data are i the shape of daily timeseries for a set of climatic variables amely, precipitatio (mm), maximum ad miimum temperature ad solar radiatio rates (MJm-2day-1). LARS-WG is based o the series weather geerator described by Rasco et al. (1991). It used semi-empirical distributios for the legths of wet ad dry day series, daily precipitatio ad daily solar radiatio. Suitable large-scale predictors are selected usig correlatio aalyses ad partial correlatios betwee predictors (large-scale atmospheric variables) ad predictats (local surface variables) i the area uder study. The simulatio of a precipitatio evet is modelled as a alterate wet ad dry series where a wet day is defied to be a day with the precipitatio rate of > 0.0 mm. The legth of each series is radomly selected from the wet or dry semi-empirical distributios for the moth whe the series starts. I determiig the distributios, the observed series are also allocated to the moth whe they start. For a wet day, the precipitatio value is geerated from the semi-empirical precipitatio distributio for the particular moth idepedet from the legth of the wet series or the amout of precipitatio i previous days. Daily miimum ad maximum temperature rates are cosidered as stochastic processes with daily meas ad daily stadard deviatios i the wet or dry status of the day. The techique used to simulate the process is very similar to that oe preseted by Rasco et al. (1991). LARS-WG performs the process of geeratig sythetic weather data with three distict steps: 1. Model Calibratio - SITE ANALYSIS the observed weather data are aalysed to determie their statistical characteristics. This iformatio is stored i two parameter files. 2. Model Validatio - QTEST - the statistical characteristics of the observed ad sythetic weather data are aalysed to determie whether there are ay sigificat differeces statistically. 3. Geeratio of Sythetic Weather Data - GENERATOR - the parameter files derived from the observed weather data durig the model calibratio process are used to geerate sythetic weather data havig the same statistical characteristics as the origial observed data, but they are differet o a day-to-day basis. Sythetic data correspodig to a particular climatic chage sceario may also be geerated by applyig global climate model derived from the chages i precipitatio, temperature ad solar radiatio rates for the LARS-WG parameter files. At the begiig, the processig ad sortig of climatic parameters were

5 Joural of Ragelad Sciece, 2013, Vol. 3, No. 3 Saadatfar et al. / 269 performed. The, the model was ru for the base period ad model calibratio was completed. The ext step was evaluated usig statistical methods such as NASH (Eq. 1), Root mea square error (Eq. 2), Mea absolute error (Eq. 3) ad Bias model performace (Eq. 4). (1) (2) (3) NA 1 RSME MAE i 1 i 1 i 1 i 1 (Yi Xi)2 (Xi Xi)2 (Xi Yi)2 Xi Yi 2 1 (4) Bias ( Xi Yi)2 i 1 Where X i = observed data Y i = Simulated data = Total umber of samples After reviewig the results of the statistical methods, high performace of Lars-WG Model was demostrated. With this model, daily value of meteorological parameters durig was simulated. The simulatio was doe uder A2, A1B ad B1 scearios. Mothly ormal climatic parameters were calculated for based o three scearios. The, mothly ad seasoal variatios of these parameters were obtaied uder the scearios of A2, A1B ad B1. 3. Results Compariso of results showed o sigificat differece betwee the modelled values ad the actual values (P<0.05). (Table 1), shows Pearso correlatio coefficiet of all parameters. These values represet the accuracy of LARS-WG to simulate the climatic parameters. I (Table 2), NASH (NA), Root Meas Square Error (RMSE), Mea Absolute Error (MAE) ad Bias show high accuracy (whe the value of NA is closer to oe, Bias is closer to zero, RMSE ad MAE have the miimum values whereas the observed ad simulated values have more similarities). Based o these results durig , the observed ad simulated values have high similarities. Observatio ad modellig values of parameters such as the absolute miimum temperature, absolute maximum temperature, precipitatio ad sushie hours with a stadard deviatio coefficiet show that this model ca simulate the treds withi the data very well. Table 1. Pearso correlatio coefficiets of the observed ad simulated values i the model durig BAFT statio Raifall Mi Tem Max Tem Sushie Hours Correlatio ** 0.98 ** 0.99 ** 0.99 ** 0.98 Weighted correlatio **=Sigificat at 1% probability level Table 2. Evaluatio idicators BAFT Statio Raifall Mi Tem Max Tem Sushie Hours MAE RSME Bias NA The observed ad simulated climatic parameters durig by LARS- WG model are show i (Figs. 3-6). It represets the ability of the model to geerate daily data o climate parameters which may be cosistet with the research coducted by Semeov (2007).

6 J. of Rage. Sci., 2013, Vol. 3, No. 3 Statistical / 270 Fig. 3. Mea mothly precipitatio ( ) Fig. 4. Mea mothly sushie hours ( ) Fig. 5. Mea mothly maximum temperature rates ( ) Mea mothly values of climatic parameters ad their chages uder the baselie period ad future scearios Fig. 6. Mea mothly miimum temperature rates ( ) (HadCM3 model scearios) are give i (Table 3). Table 3. Mea mothly values of climatic parameters ad their chages uder the baselie period ad future scearios Parameters Scearios Ja Feb Mar Apr May Ju Jul Aug Sep Oct Nov Des Normal Raifall Variatios Miimum temperatures Variatios Maximum temperatures Variatios Baselie A1B A B A1B A B Baselie /04 A1B A B A1B A B Baselie A1B A B A1B A B

7 Joural of Ragelad Sciece, 2013, Vol. 3, No. 3 Saadatfar et al. / 271 The results from the aalysis of climatic parameters showed that i the study area, the most sigificat chages of precipitatio durig computed as 6.7% reductio will occur uder the A2 sceario. After that, A1B ad B1 scearios with the decrease rates of precipitatio as 5.8% ad 5.1% have the highest percetage of variatios, respectively (Fig. 7). Mea chages i sushie hours o a average of 0.04 hours will decrease uder the B1 sceario ad this parameter will icrease uder the A1B ad A2 scearios (Fig. 8). Fig. 7. Precipitatio variatios durig The mea miimum ad maximum temperature variatios durig are icreased uder all three scearios. The highest variatio rate i these Fig. 8. Sushie variatios durig parameters will occur uder the A1B sceario with a average of 0.82 ad 0.73 C (Figs. 9 ad 10). Fig. 9. Miimum temperature variatio durig Aalysis of seasoal parameters uder climate scearios for showed that sprig ad summer raifall variatios Fig. 10. Maximum temperature variatio durig uder all three scearios will decrease ad the icrease of them will occur oly i witer (Fig. 11). Fig. 11. Seasoal precipitatio variatio

8 J. of Rage. Sci., 2013, Vol. 3, No. 3 Statistical / 272 Geerally, the miimum ad maximum temperature rates will icrease i all seasos regardig three scearios. The A1B ad A2 scearios have the highest ad lowest variatios cocerig the three scearios, respectively (Figs. 12 ad 13). Fig. 12. Seasoal maximum temperature variatio Data aalysis showed that sushie hours will have a decreasig tred i witer uder all three scearios ad a Fig. 13. Seasoal miimum temperature variatio icreasig tred i the sushie hours i the other seasos is show i Fig Discussio I this paper, for evaluatig ad uderstadig the climatic chages i the Khabr ragelad i Kerma provice durig , log-term predictios of a atmospheric geeral circulatio model (HadCM3) were dowscaled by LARS-WG model. The results showed that this model has a high efficiecy i the simulatio of daily climatic parameters which cofirms the results of research coducted by Elashmay et al. (2005) ad Semeov ad Barrow (2002). Dowscaled data by HadCM3 model based o three scearios of A1B, Fig. 14. Seasoal Sushie hours variatios A2 ad B1 for have idicated that maximum ad miimum temperature rates will icrease with the average values of ad ( C), respectively. Thus, the average temperature rate will be icreased. Furthermore, a icreasig tred will be observed i the umber of sushie hours. O the other had, precipitatio rate will be decreased to (mm) uder all three scearios. These results are i agreemet with the results of Kousari et al. (2010) ad Ragab ad Prudhomme (2002).

9 Joural of Ragelad Sciece, 2013, Vol. 3, No. 3 Saadatfar et al. / 273 Based o the results, the climate i the Khabr regio for the ext 30 years will markedly be differet from the curret situatio as the largest decrease of precipitatio rate (4-6%) will occur i sprig ad autum as compared to the baselie precipitatio i each sceario. Miimum ad maximum temperature rates also showed a icreasig tred i sprig ad autum i all three scearios. This is cosistet with the fidigs reported by Abasi et al. (2010). They stated that temperature rates would icrease to 0.3 C, ad most of it will be i witer. The observed treds i precipitatio ad temperature may cause sowfall to be reduced. I cotrast, heavy rais will be icreased. The cosequece of that will be a reductio i the storage ad supply of water through the gradual meltig of sow i the moutaious areas. This heavy raifall leads to icrease the damage to atural ecosystem ad people; o the other had, fertile soils will be lost. Udoubtedly, climatic chages are affectig dry lads ad pastoral livelihoods. As a result, these areas will ted to become drier, ad the existig water shortages will be worseed. I additio, climatic chages are likely to brig about eve more erratic ad upredictable raifalls ad most extreme weather coditios such as loger ad more frequet droughts. Where this happes, the delicate balace o which pastoral systems deped is udermied. Saadatfar et al. (2010) reported that chages i climatic parameters may cause to ifluece the growth behaviour of plats ad ragelad exploitatios. The chages i the umber of freezig days may cause to alter the plat regeeratio. Moreover, the earliest start of growig period leads to the chages of exploitatio times as well as pastorals caledar. Apart from temporal chages, there are some impacts o spatial aspects i the moutaious ecosystems due to the metioed thermal icrease, i.e. chages i the existece boudaries of plat species ad commuities, their expasio to higher altitudes ad shrikage of meadows. Muaga et al. (2010) suggested that it is essetial to amalgamate across iformatio types (i.e. weather, climate, socio-ecoomy, policy ad ecology) to admoish those ivolved i decisio-makig better for the ecosystem maagemet. The preparatio of climate iformatio ad a uderstadig of ecosystem resposes to climate chages ad variability eed to support all the plaig ad decisiomakig processes for the future. With assessig the ragelad climate cocerig the climatic chages scearios, it is possible to realize the rates of chages i raifall seasos ad periods, severe droughts, floods, pest outbreaks, river flow declie, wetlads dryig ad expasio ad itesificatio of dust storms i the future ad based o them, risk i the ragelads should be effectively maaged. This maagemet approach ca reduce the ragelad vulerability ad empower the ragelad beeficiaries i copig ad adaptig the critical situatios. Literature Abassi, F., Malbusi, S., Babaeia, I., Asmari, M., ad Borhai, R., Climate chage predictio of south Khorasa provice durig by usig statistical dowscalig of ECHO-G data. Jour. Water ad Soil, 24(2): (I Persia). Elshamy, M. E., Wheater, H. S., Gedey, N. ad Hutigford, C., Evaluatio of the raifall compoet of weather geerator for climate chage studies. Jour. Hydrology. 326: Hall, W. B., McKeo, G. M., Carter, J. O., Day, K. A., Howde, S. M., Scala, J., Johsto, P. ad Burrows W. H., Climate chage i Queeslad's grazig lads: II. A assessmet of the impact o aimal productio from ative pastures. Jour. Ragelad. 20:

10 J. of Rage. Sci., 2013, Vol. 3, No. 3 Statistical / 274 IPCC-TGCIA, "Geeral Guidelies o the Use of Sceario Data for Climate Impact ad Adaptatio Assessmet. Versio 2. Prepared by T. R. Carter o Behalf of the Itergovermetal Pael o Climate Chage, Task Group o Data ad Sceario Support for Impact ad Climate Assessmet. pp. 66. Kousari, M. R., Ekhtesasi, M. R., Tazeh, M. ad Zarch, M. A. A., A ivestigatio of the Iraia climatic chages by cosiderig the precipitatio, temperature, ad relative humidity parameters. Jour. Theor Appl Climatol. 23: (I Persia). Muaga, R., Rivigtob, M., Taklec, E. S., Mackeyd, B., Thiawa, I. ad Liua, J., Climate Iformatio ad Capacity Needs for Ecosystem Maagemet uder a Chagig Climate. Procedia Evir. Sci. 1: Solomo, S., Qi, D., Maig, M., Che, Z., Marquis, M., Averyt, K. B., Tigor, M. ad Miller, H. L., IPCC, Climate Chage. The Physical Sciece Basis. Cotributio of Workig Group I to the Fourth Assessmet Report of the Itergovermetal Pael o Climate Chage, Cambridge, Uited Kigdom ad New York, NY, USA: Cambridge Uiversity Press. Wilby, R. L., Dawso, C. W. ad Barrow, E. M., SDSM - a Decisio Support Tool for the Assessmet of Regioal Climate Chage Impacts. Jour. Evirometal Modellig ad Software. 17: Ragab, R. ad Prudhomme, C., Climate chage ad water resources maagemet i arid ad semi-arid regios: prospective ad challeges for the 21 st cetury. Jour. Biosys Eg. 81: Rasco, P., Szeidl, L. ad Semeov, M. A., A serial approach to local stochastic models. Jour. Ecological Modellig, 57: Saadatfar, A., Barai, H. ad Bahremad, A., Thermal chages i Ira-Touraia Regio. The Effects o Ragelad. Iteratioal Workshop o Climate ad Evirometal Chage. Beijig, Chia Page (I Persia). Semeov, M. A., Developmet of high resolutio UKCIP02-based climate chage scearios i the UK. Jour. Agri, Meteoro. 144(1-2): Semeov, M. A., Simulatio of extreme weather evets by a stochastic weather geerator. Clim, Res. 35(1): Semeov, M. A. ad Barrow, E., Lars-WG a Stochastic Weather Geerator for Use i Climate Impact Studies. Versio 3.0. User Maual. Climate Chage Scearios. Jour. Climatic Chage, 35: Semeov, M. A. ad Stratoovitch, P., The use of multi-model esembles from global climate models for impact assessmets of climate chage, Clim. Res. 41(1): 1-14.

11 س Joural of Ragelad Sciece, 2013, Vol. 3, No. 3 Saadatfar et al. / 275 پیفثی ی تغییطات فه ی پبضا تط بی ال ی ی طاتغ ثب اؾتفبز اظ ضیع میبؼ بیی زاز بی HadCM3 ) طب ؼ ضزی: طاتغ ذجط وط ب ( چکیده ا یط ؾؼبزتفط زا كد ی زوتطای طتؼساضی زا ك ب ػ وكب ضظی بثغ طجیؼی ط ب ) یؿ س ؿئ ( حؿی ثبضا ی زا كیبض ط طتؼساضی زا ك ب ػ وكب ضظی بثغ طجیؼی ط ب ػجسا طضب ث ط س زا كیبض ط آثریعزاضی زا ك ب ػ وكب ضظی بثغ طجیؼی ط ب ػ یطضب ؿبح ث ا ی زا كیبض ط بثغ آة پطزیؽ اث ضیحب زا ك ب ت طا ػبز ؾپ طی اؾتبز ط طتؼساضی زا ك ب ػ وكب ضظی بثغ طجیؼی ط ب اح س ػبثسی ؾط ؾتب ی اؾتبزیبض ط تط یح آ ظ وكب ضظی زا ك ب ػ وكب ضظی بثغ طجیؼی ط ب طاتغ یىی اظ آؾیتپصیطتطی ثرف ب بقی اظ اثطات تغییط ال ی یثبق س. ای تأثیط زض بطك ذكه ی ذكه زض خبیی و طاتغ زض قطایط ثحطا ی لطاض زاض س ثیكتط اؾت. ث بثطای ق بذت پ یبیی الؼی تغییط ال ی ثط طاتغ ثؿیبض اؾت. سف اظ ای تحمیك تؼیی تغییط ال ی زض طم ذجط وط ب یثبقس. زض ای ضاؾتب چ بض د ػ اظ زاز بی اق بؾی س HadCM3 قب حساوثط ز ب حسال ز ب ثبض ؾبػبت آفتبثی تحت ؾ ؾ بضی ی A1B A2 B1 ثطای تؼیی تغییط ال ی زض طم ذجط ضز اؾتفبز لطاض طفت. زض ای تحمیك ث ظ ض اضظیبثی تغییط ال ی زض ز ض اظ زاز بی س HadCM3 و ثب اؾتفبز اظ س LARS-WG تحت ؾ بضی بی A1B A2 B1 ضیع میبؼ طزیس س ؾ بضی زاضای ض س وب كی اؾت. اؾتفبز قس. تبیح كب زاز و یعا ثبض زض ز فه ث بض تبثؿتب طجك ط ؾ ز بی و ی ثیكی زض فه ض س افعایكی ذ ا س زاقت ت ب ؾبػبت آفتبثی زض فه ظ ؿتب ض س وب كی اظ ذ ز كب زاز. ثط اؾبؼ ؾ بضی A1B ز بی و ی ثیكی ثیكتطی ض س افعایكی ضا زاقت س. ؾبػبت آفتبثی مساض ثبض یع ث تطتیت ثیكتطی ض س افعایكی وب كی ضا زض ؾ بضی A2 زاضا ث ز س. ػال ثط ای افعایف زض حساوثط حسال زضخ حطاضت ث ط ض ت ؾط ثیكتط اظ صقت ث ز اؾت زض تید ثب خ ز ض س افعایكی ز بی و ی ثیكی افعایف ز بی ت ؾط ا زض ای ز ض لبث ا تظبض ذ ا س ث ز. طجك ای تبیح قطایط ال ی ی طاتغ ذجط زض 30 ؾب آتی تفب ت حؿ ؾی ثب قطایط فؼ ی ذ ا س زاقت ثط ب ضیعی بی ث س ست اؾتطاتػیه ثطای سیطیت ؾبظ بض ثب ای قطایط ضط ضی ث ظط یضؾس. کلمات کلیدی: پبضا تط بی ال ی ی LARS-WG HadCM3 طاتغ ذجط