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Yayın Projected changes in temperature and precipitation climatology of Central Asia CORDEX Region 8 by using RegCM4.3.5(Elsevier Ltd, 2017-01-01) Öztürk, Tuğba; Turp, Mustafa Tufan; Türkeş, Murat; Kurnaz, Mehmet LeventThis work investigated projected future changes in seasonal mean air temperature (°C) and precipitation (mm/day) climatology for the three periods of 2011–2040, 2041–2070, and 2071–2100, with respect to the control period of 1971–2000 for the Central Asia domain via regional climate model simulations. In order to investigate the projected changes in near future climate conditions, the Regional Climate Model, RegCM4.3.5 of the International Centre for Theoretical Physics (ICTP) was driven by two different CMIP5 global climate models. The HadGEM2-ES global climate model of the Met Office Hadley Centre and the MPI-ESM-MR global climate model of the Max Planck Institute for Meteorology were downscaled to 50 km for the Coordinated Regional Climate Downscaling Experiment (CORDEX) Region 8. We investigated the seasonal time-scale performance of RegCM4.3.5 in reproducing observed climatology over the domain of the Central Asia by using two different global climate model outputs. For the future climatology of the domain, the regional model projects relatively high warming in the warm season with a decrease in precipitation in almost all parts of the domain. A warming trend is notable, especially for the northern part of the domain during the cold season. The results of our study show that surface air temperatures in the region will increase between 3 °C and about 7 °C on average, according to the emission scenarios for the period of 2071–2100 with respect to past period of 1971–2000. Therefore, the projected warming and decrease in precipitation might adversely affect the ecological and socio-economic systems of this region, which is already a mostly arid and semi-arid environment.Yayın Projections of climate change in the Mediterranean Basin by using downscaled global climate model outputs(Wiley-Blackwell, 2015-11-30) Öztürk, Tuğba; Ceber, Zeynep Pelin; Türkeş, Murat; Kurnaz, Mehmet LeventThe Mediterranean Basin is one of the regions that shall be affected most by the impacts of the future climate changes on hydrology and water resources. In this study, projected future changes in mean air temperature and precipitation climatology and inter-annual variability over the Mediterranean region were studied. For performing this aim, the future changes in annual and seasonal averages for the future period of 2070-2100 with respect to the period from 1970 to 2000 were investigated. Global climate model outputs of the World Climate Research Program's Coupled Model Intercomparison Project Phase 3 multi-model dataset were used in this work. Intergovernmental Panel on Climate Change SRES A2, A1B and B1 emission scenarios' outputs were used in future climate model projections. Future surface mean air temperatures of the larger Mediterranean basin increase mostly in summer and least in winter, and precipitation amounts decrease in all seasons at almost all parts of the basin. Future climate signals for air temperature and total precipitation values are much larger than the inter-model standard deviation. Inter-annual temperature variability increases evidently in summer season and decreases in the northern part of the domain in the winter season, while precipitation variability increases in almost all parts of domain. Probability distribution functions are found to be shifted and flattened for future period compared to the reference period. This indicates that the occurrence of frequency and intensity of high temperatures and heavy precipitation events will likely increase in the future period.Yayın Future projections of temperature and precipitation climatology for CORDEX-MENA domain using RegCM4.4(Elsevier Science Inc, 2018-07-01) Öztürk, Tuğba; Turp, Mustafa Tufan; Türkeş, Murat; Kurnaz, Mehmet LeventIn this study, we investigate changes in seasonal temperature and precipitation climatology of CORDEX Middle East and North Africa (MENA) region for three periods of 2010-2040, 2040-2070 and 2070-2100 with respect to the control period of 1970-2000 by using regional climate model simulations. Projections of future climate conditions are modeled by forcing Regional Climate Model, RegCM4.4 of the International Centre for Theoretical Physics (ICTP) with two different CMIP5 global climate models. HadGEM2-ES global climate model of the Met Office Hadley Centre and MPI-ESM-MR global climate model of the Max Planck Institute for Meteorology were used to generate 50 km resolution data for the Coordinated Regional Climate Downscaling Experiment (CORDEX) Region 13. We test the seasonal time-scale performance of RegCM4.4 in simulating the observed climatology over domain of the MENA by using the output of two different global climate models. The projection results show relatively high increase of average temperatures from 3 degrees C up to 9 degrees C over the domain for far future (2070-2100). A strong decrease in precipitation is projected in almost all parts of the domain according to the output of the regional model forced by scenario outputs of two global models. Therefore, warmer and drier than present climate conditions are projected to occur more intensely over the CORDEX-MENA domain.Yayın The emergence of projected scaled patterns of extreme temperatures over Europe(Frontiers Media SA, 2023-06-28) Öztürk, Tuğba; Canbaz, Emine; Bilgin, Başak; Matte, Dominic; Kurnaz, Mehmet Levent; Christensen, Jens HesselbjergThis work investigates the scalability of extreme temperatures over the European domain with global warming levels. We have used the EURO-CORDEX ensemble of regional model simulations at 0.11° resolution for daily minimum and maximum temperatures to analyze future changes in extreme weather daily events. Scaling with the annual mean global warming modeled by the driving GCM was applied to future extreme temperature indices changes. Regional changes in each index were scaled by corresponding global warming levels obtained from GCMs. This approach asserts that regional patterns of climate change and average global temperature change are linearly related. It can provide information regarding climate change for periods or emission scenarios when no simulations exist. According to the results, the annual minimum of the lowest temperature of the day (TNn) increases more than the annual maximum of the highest temperature of the day (TXx) for Europe. The multi-model mean of the changes in scaled patterns of extreme temperatures emerges early, around 2020, even before it becomes robust. Individual scaled patterns of TNn and TXx emerge from around 2040.Yayın Impacts of climate change on precipitation climatology and variability in Turkey(Springer International Publishing Ag, 2020) Türkeş, Murat; Turp, M. Tufan; An, Nazan; Öztürk, Tuğba; Kurnaz, Mehmet LeventIn this chapter, changes in seasonal precipitation climatology, extreme weather conditions, and aridity conditions of Turkey are evaluated for the period of 2021-2050 with respect to the reference period of 1971-2000 by using regional climate model simulations. Projections of future climate conditions are modeled by forcing Regional Climate Model, RegCM4.4 of the International Centre for Theoretical Physics (ICTP) with MPI-ESM-MR global climate model of the Max Planck Institute for Meteorology. The outputs of MPI-ESM-MR are used to generate 10 km resolution data by the double nesting method under both RCP4.5 and RCP8.5 emission scenarios. The seasonal time-scale performance of RegCM4.4 in reproducing the observed climatology over Turkey is tested by using the output of the global climate model. The projection results show a strong decrease in precipitation for almost all parts of the domain according to the output of the regional model. The intensity of drought conditions is projected to increase. According to the projection results, more arid conditions are expected in the region for the near future. Therefore, drier than present climate conditions are projected to occur more intensely over Turkey.Yayın Technical climate change adaptation options of the major ski resorts in Bulgaria(Springer International Publishing, 2016-01-01) Demiroğlu, Osman Cenk; Turp, Mustafa Tufan; Öztürk, Tuğba; An, Nazan; Kurnaz, Mehmet LeventClimate change has been and increasingly will be a major threat to the ski tourism industry, whose survival is highly dependent on the existence of snow cover of sufficient depth and duration. For this matter, it is even now more usual for the ski resorts to adapt to this issue by various measures at the technical, operational, and political levels. Technically speaking, snowmaking has become the method most used throughout the industry to combat the immediate impacts of climate change, while moving the ski areas to higher terrains has been standing out as an another option, wherever available and feasible. In this study, the aim is to project the future climatic changes in snowmaking capacity; in other words, technical snow reliability, and the moving requirements, if any, of the four major ski resorts in Bulgaria for the period of 2016-2030 with respect to the control period of 1991- 2005. For this purpose, the past and the future climatic conditions for the technical snow reliability of the ski resorts and their immediate surroundings are determined by the temperature and the relative humidity values generated and projected through the Regional Climate Model RegCM 4.4 of the Abdus Salam International Centre for Theoretical Physics (ICTP) by scaling the global climate model MPI-ESM-MR of Max Planck Institute for Meteorology down to a resolution of 10 km. The model is further processed according to the recent RCP 4.5 and RCP 8.5 concentration scenarios of the IPCC. The model outputs on air temperature and relative humidity are utilized for determination of wet-bulb temperatures through psychographic conversions that ultimately provide us with thresholds for snowmaking limits. Findings display the temporal changes in the snowmaking hours of the ski resorts at various altitudinal levels calculated according to the environmental lapse rates. Such displays can guide the practitioners in considering investment lives and moving the ski resorts according to optimistic and pessimistic projections.Yayın Global exposure of population and land-use to meteorological droughts under different warming levels and SSPs: A CORDEX based study(John Wiley and Sons Ltd, 2021-12) Spinoni, Jonathan; Barbosa, Paulo; Bucchignani, Edoardo; Cassano, John; Cavazos, Tereza; Cescatti, Alessandro; Christensen, Jens Hesselbjerg; Christensen, Ole Bossing; Coppola, Erika; Evans, Jason; Forzieri, Giovanni; Geyer, Beate; Giorgi, Filippo; Jacob, Daniela; Katzfey, Jack; Koenigk, Torben; Laprise, Rene; Lennard, Christopher John; Kurnaz, Mehmet Levent; Li, Delei; Llopart, Marta; McCormick, Niall; Naumann, Gustavo; Nikulin, Grigory; Öztürk, Tuğba; Panitz, Hans-Jurgen; da Rocha, Rosmeri Porfirio; Solman, Silvina Alicia; Syktus, Jozef; Tangang, Fredolin; Teichmann, Claas; Vautard, Robert; Vogt, Jurgen Valentin; Winger, Katja; Zittis, George; Dosio, AlessandroGlobal warming is likely to cause a progressive drought increase in some regions, but how population and natural resources will be affected is still underexplored. This study focuses on global population and land-use (forests, croplands, pastures) exposure to meteorological drought hazard in the 21st century, expressed as frequency and severity of drought events. As input, we use a large ensemble of climate simulations from the Coordinated Regional Climate Downscaling Experiment, population projections from the NASA-SEDAC dataset, and land-use projections from the Land-Use Harmonization 2 project for 1981-2100. The exposure to drought hazard is presented for five SSPs (SSP1-SSP5) at four Global Warming Levels (GWLs, from 1.5 to 4 degrees C). Results show that considering only Standardized Precipitation Index (SPI; based on precipitation), the combination SSP3-GWL4 projects the largest fraction of the global population (14%) to experience an increase in drought frequency and severity (vs. 1981-2010), with this value increasing to 60% if temperature is considered (indirectly included in the Standardized Precipitation-Evapotranspiration Index, SPEI). With SPEI, considering the highest GWL for each SSP, 8 (for SSP2, SSP4, and SSP5) and 11 (SSP3) billion people, that is, more than 90%, will be affected by at least one unprecedented drought. For SSP5 (fossil-fuelled development) at GWL 4 degrees C, approximately 2 center dot 10(6) km(2) of forests and croplands (respectively, 6 and 11%) and 1.5 center dot 10(6) km(2) of pastures (19%) will be exposed to increased drought frequency and severity according to SPI, but for SPEI, this extent will rise to 17 center dot 10(6) km(2) of forests (49%), 6 center dot 10(6) km(2) of pastures (78%), and 12 center dot 10(6) km(2) of croplands (67%), with mid-latitudes being the most affected areas. The projected likely increase of drought frequency and severity significantly increases population and land-use exposure to drought, even at low GWLs, thus extensive mitigation and adaptation efforts are needed to avoid the most severe impacts of climate change.Yayın The Climate Change Impacts on the regional crop yield in Turkey(European Geosciences Union (EGU), 2015-04-17) An, Nazan; Turp, Mustafa Tufan; Öztürk, Tuğba; Kurnaz, Mehmet LeventThis paper emphasizes the relationship between climate change and crop yield in Turkey and discusses how the variables representing the climate change impacts affect the regional crop yield in Turkey. The impacts of climate change are represented as the function of vulnerability for the period of 1980-2010. There are 2 steps in this research. Firstly, regional climate modeling is conducted for obtaining to the climatic parameters, namely total precipitation and mean air temperature. We focus on the role of those climatic variables on the crop yield. The projections were performed according to the scenarios of IPCC, namely RCP4.5 and the RCP8.5. According to the regional model results, it is seen that there will be an increase up to the 4 ◦C in mean air temperatures of Turkey for the period of 2020 – 2050 with respect to the period of 1970 – 2000 and also precipitation climatology of Turkey shows a decrease up to 1.2 mm/day. In the second part of the study, climatic parameters are combined and interpreted together through the panel data analysis and we examined that how the variables representing the climate change impacts have an influence on the crop yield in the some crucial regions for the crop production of Turkey. Estimated risks for crops in the panel data analysis differ from each other resulting from increase in temperature and decrease in rainfall.Yayın Simulating the climatology of extreme events for the Central Asia domain using the RegCM 4.0 regional climate model(Springer-Verlag Berlin Heidelberg, 2012-01-01) Altınsoy, Hamza; Öztürk, Tuğba; Türkeş, Murat; Kurnaz, Mehmet LeventIn this work, future changes in the frequency of the seasonal extreme climate events such as number, frequency, duration and intensity of heat waves (5 consecutive temperature days above the maximum temperature calendar day 90th percentiles, number of days per year that is above the same percentiles and greatest number of consecutive days above these percentiles) for the period of 2071–2100 over Central Asia (18.56 –70.13 East and 7.28 –142.4 North) with respect to the present period of 1971–2000 were studied in detail. Regional Climate Model RegCM 4.0 of Abdus Salam International Center for Theoretical Physics (ICTP) with ECHAM5 forcing data was used for hindcast and forecast projection. This region will very likely be affected by heat waves in winter and spring seasons and heat wave frequency, intensity and duration will increase significantly over the Arabian Peninsula in summer. On the other hand, cold spells will not change as much as heat waves over the region in all seasons.Yayın Projections for changes in natural and technical snow reliability of a major Turkish ski resort by using RegCM4.3.5(European Geosciences Union (EGU), 2014-05-02) Öztürk, Tuğba; Demiroğlu, Osman Cenk; Turp, Mustafa Tufan; Türkeş, Murat; Kurnaz, Mehmet LeventClimate change has been and increasingly will be a major threat to the ski tourism industry whose survival is highly dependent on existence of snow cover of sufficient depth and duration. The common knowledge requires that in order for a ski resort to be viable, it has to perform operations for at least 100 days in seven out of ten winters. For this matter, it is now even more usual for the ski resorts to adapt to this issue by technical snowmaking. In this study, projected future changes for the period of 2010-2040, 2040-2070, and 2070-2100 in air temperature, relative humidity, and snow depth climatology and variability with respect to the control period of 1970-2000 were assessed for the domain of a major ski resort in Turkey. Regional Climate Model (RegCM4.3.5) of ICTP (International Centre for Theoretical Physics) was used for projections of future and present climate conditions. HadGEM2 global climate model of the Met Office Hadley Centre, MPI-ESM-MR of the Max Planck Institute for Meteorology, GFDL-ESM2M of the National Oceanic and Atmospheric Administration Geophysical Fluid Dynamics Laboratory were downscaled to 10 km for the resort and its surrounding region. Both the projections and the downscaling were realized according to the RCP4.5 and the RCP8.5 emission scenarios of the IPCC. The outputs on snow depth were used for a count of the changes on snow cover duration sufficient for skiing actitivies, signaling natural snow-reliability, whereas the outputs on air temperature and relative humidity were utilized for determination of wet-bulb temperatures. The latter measure was used to interpret the changes in the snowmaking capacity, in other words; technical snow-reliability, of the resort.
