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    Projecting climate change, drought conditions and crop productivity in Turkey
    (Inter-Research, 2012) Sen, Burak; Topcu, Sevilay; Turkes, Murat; Sen, Baha; Warner, Jeoren F.
    This paper focuses on the evaluation of regional climate model simulation for Turkey for the 21st century. A regional climate model, ICTP-RegCM3, with 20 km horizontal resolution, is used to downscale the reference and future climate scenario (IPCC-A2) simulations. Characteristics of droughts as well as the crop growth and yields of first- and second-crop corn are then calculated and simulated based on the data produced. The model projects an increase in air temperature of 5 to 7 degrees C during the summer season over the west and an increase of 3.5 degrees C for the winter season for the eastern part of the country. Precipitation is predicted to be 40% less in the southwest, although it may increase by 25% in the eastern part of the Black Sea region and north eastern Turkey. Trends in drought intensity and crop growth are related to climate changes. The results suggest more frequent, intense and long-lasting droughts in the country particularly along the western and southern coasts under future climate conditions. A shift of climate classes towards drier conditions is also projected for the western, southern and central regions during the 21st century. Evaluating the role of the climate change trends in crop production reveals significant decreases in yield and shortened growth seasons for first-and second-crop corn, a likely result of high temperatures and water stresses. In addition to rising temperatures and declining precipitation, increasing frequency, severity and duration of drought events may significantly affect food production and socio-economic conditions in Turkey. Our results may help policy makers and relevant sectors to implement appropriate and timely measures to cope with climate-change-induced droughts and their effects in the future.
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    VALIDATION OF DAILY PRECIPITATION ESTIMATES OF THE REGIONAL CLIMATE MODEL REGCM4 OVER THE DOMAINS IN TURKEY WITH NWP VERIFICATION TECHNIQUES
    (Parlar Scientific Publications (P S P), 2014) Sen, Burak; Kilinc, Recep; Sen, Baha; Sonuc, Emrullah
    We present a validation study for a 50-km resolution version of the RegCM4 regional climate model over the East Mediterranean Basin. In this study, the observation and evaluation of the model results against each other as well as graphication, which mostly generates scatter plot graphs of the atmosphere for operational weather forecasting models (NWP, numerical weather prediction), with 11 different statistical verification score values were evaluated by calculating the regional climate model results. As a result of the analysis, it has been estimated that the rainfall is 42% higher than the estimated average amount RegCM4 simulations based on the 50 observation stations. Meteorological Service (TSMS, Turkish State Meteorological Service) observation network monitored 50 stations based on the average of Frequency Bias Index (FBI), Proportion Correct (PC), Probability of Detection (POD), False Alarm Ratio (FAR), False Alarm Rate (F), Hanssen-Kuipers Skill Score (KSS), the Threat Score (TS), Equitable Threat Score (ETS), Heidke Skill Score (HSS), The Odds Ratio (OR), and Odds Ratio Skill Score (ORSS) values which are as follows, respectively: 0.70, 0.70, 0.52, 0.32, 0.38, 0.39, 0.21, 0.34, 5.99, and 0.69. The objective score values calculated for RegCM4 climate model were found to be close to the score values of the NWP models. Given these values, which were found to be successful for RegCM4 model dynamics, the results generated by other models, recovery/adaptation techniques will be used for the application of hydrological studies.
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    Verifying regional climate model results with web-based expert-system
    (Elsevier Science Bv, 2012) Sonuc, Emrullah; Sen, Baha; Sen, Burak
    The verification system aims at monitoring the forecast quality over time. Verification helps improving the forecast quality by knowing the strengths and weaknesses of the existing forecasting system and by comparing the quality of different forecasting methodologies. Thus, the web-based verification system has been developed for verification of forecast results that is produced by International Center for Theoretical Physics Regional Climate Model v4 for our country. The forecasters and analysts can analyze the data in real-time with this web-based system. In this study, model values obtained from the system provided by ULAKBIM High Performance and Grid Computing Center. Model and station values were compared with each other for verification of model results with observation values. Therefore model grid values are transferred to station by using bi-linear and nearest neighbor (k-NN) (proximal) interpolation methods. This process in meteorological literature is called grid to point technique. Verification methods for forecasts of continuous variables are used to verify forecast values with observation values. Some verification methods; Mean Error, Mean Absolute Error and Root Mean Square Error, are calculated for validation. Verification results are shown as table and graphics on web-based system which is developed by the power of PHP (PHP: Hypertext Preprocessor). (C) 2011 Published by Elsevier Ltd.