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Yayın Quaternary uplift of the northern margin of the Central Anatolian Plateau: New OSL dates of fluvial and delta-terrace deposits of the Kizilirmak River, Black Sea coast, Turkey(Pergamon-Elsevier Science Ltd, 2018-12-01) Berndt, Christopher; Yıldırım, Cengiz; Çiner, Tahsin Attila; Strecker, Manfred R.; Ertunç, Gülgün; Sarıkaya, Mehmet Akif; Özcan, Orkan; Öztürk, Tuğba; Güneç Kıyak, NafiyeWe analysed the interplay between coastal uplift, sea level change in the Black Sea, and incision of the Kizilirmak River in northern Turkey. These processes have created multiple co-genetic fluvial and marine terrace sequences that serve as excellent strain markers to assess the ongoing evolution of the Pontide orogenic wedge and the growth of the northern margin of the Central Anatolian Plateau. We used high-resolution topographic data, OSL ages, and published information on past sea levels to analyse the spatiotemporal evolution of these terraces; we derived a regional uplift model for the northward advancing orogenic wedge that supports the notion of laterally variable uplift rates along the flanks of the Pontides. The best-fit uplift model defines a constant long-term uplift rate of 0.28 +/- 0.07 m/ka for the last 545 ka. This model explains the evolution of the terrace sequence in light of active tectonic processes and superposed cycles of climate-controlled sea-level change. Our new data reveal regional uplift characteristics that are comparable to the inner sectors of the Central Pontides; accordingly, the rate of uplift diminishes with increasing distance from the main strand of the restraining bend of the North Anatolian Fault Zone (NAFZ). This spatial relationship between the regional impact of the restraining bend of the NAFZ and uplift of the Pontide wedge thus suggests a strong link between the activity of the NAFZ, deformation and uplift in the Pontide orogenic wedge, and the sustained lateral growth of the Central Anatolian Plateau flank.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 Projected changes in extreme temperature and precipitation indices over CORDEX-MENA domain(MDPI AG, 2021-05) Öztürk, Tuğba; Saygılı Aracı, Fatma Sibel; Kurnaz, Mehmet LeventIn this study, projected changes in climate extreme indices defined by the Expert Team on Climate Change Detection and Indices were investigated over Middle East and North Africa. Changes in the daily maximum and minimum temperature-and precipitation-based extreme indices were analyzed for the end of the 21st century compared to the reference period 1971–2000 using regional climate model simulations. Regional climate model, RegCM4.4 was used to downscale two different global climate model outputs to 50 km resolution under RCP4.5 and RCP8.5 scenarios. Results generally indicate an intensification of temperature-and precipitation-based extreme indices with increasing radiative forcing. In particular, an increase in annual minimum of daily minimum temperatures is more pronounced over the northern part of Mediterranean Basin and tropics. High increase in warm nights and warm spell duration all over the region with a pronounced increase in tropics are projected for the period of 2071–2100 together with decrease or no change in cold extremes. According to the results, a decrease in total wet-day precipitation and increase in dry spells are expected for the end of the century.Yayın The Worldwide C3S CORDEX Grand Ensemble A Major Contribution to Assess Regional Climate Change in the IPCC AR6 Atlas(American Meteorological Society, 2022-12) Diez-Sierra, Javier; Iturbide, Maialen; Gutierrez, Jose M.; Fernandez, Jesus; Milovac, Josipa; Cofino, Antonio S.; Cimadevilla, Ezequiel; Nikulin, Grigory; Levavasseur, Guillaume; Kjellstrom, Erik; Bulow, Katharina; Horanyi, Andras; Brookshaw, Anca; Garcia-Diez, Markel; Perez, Antonio; Bano-Medina, Jorge; Ahrens, Bodo; Alias, Antoinette; Ashfaq, Moetasim; Bukovsky, Melissa; Buonomo, Erasmo; Caluwaerts, Steven; Chou, Sin Chan; Christensen, Ole B.; Ciarlo, James M.; Coppola, Erika; Corre, Lola; Demory, Marie-Estelle; Djurdjevic, Vladimir; Evans, Jason P.; Fealy, Rowan; Feldmann, Hendrik; Jacob, Daniela; Jayanarayanan, Sanjay; Katzfey, Jack; Keuler, Klaus; Kittel, Christoph; Kurnaz, Mehmet Levent; Laprise, Rene; Lionello, Piero; McGinnis, Seth; Mercogliano, Paola; Nabat, Pierre; Öztürk, Tuğba; Panitz, Hans-Jurgen; Paquin, Dominique; Pieczka, Ildiko; Raffaele, Francesca; Remedio, Armelle Reca; Scinocca, John; Sevault, Florence; Somot, Samuel; Steger, Christian; Tangang, Fredolin; Teichmann, Claas; Termonia, Piet; Thatcher, Marcus; Torma, Csaba; van Meijgaard, Erik; Vautard, Robert; Warrach-Sagi, Kirsten; Winger, Katja; Zittis, George; Önol, BarışThe collaboration between the Coordinated Regional Climate Downscaling Experiment (CORDEX) and the Earth System Grid Federation (ESGF) provides open access to an unprecedented ensemble of regional climate model (RCM) simulations, across the 14 CORDEX continental-scale domains, with global coverage. These simulations have been used as a new line of evidence to assess regional climate projections in the latest contribution of the Working Group I (WGI) to the IPCC Sixth Assessment Report (AR6), particularly in the regional chapters and the Atlas. Here, we present the work done in the framework of the Copernicus Climate Change Service (C3S) to assemble a consistent worldwide CORDEX grand ensemble, aligned with the deadlines and activities of IPCC AR6. This work addressed the uneven and heterogeneous availability of CORDEX ESGF data by supporting publication in CORDEX domains with few archived simulations and performing quality control. It also addressed the lack of comprehensive documentation by compiling information from all contributing regional models, allowing for an informed use of data. In addition to presenting the worldwide CORDEX dataset, we assess here its consistency for precipitation and temperature by comparing climate change signals in regions with overlapping CORDEX domains, obtaining overall coincident regional climate change signals. The C3S CORDEX dataset has been used for the assessment of regional climate change in the IPCC AR6 (and for the interactive Atlas) and is available through the Copernicus Climate Data Store (CDS).Yayın Future global meteorological drought hot spots: A study based on CORDEX data(American Meteorological Society, 2020-05-01) Spinoni, Jonathan; Barbosa, Paulo; Bucchignani, Edoardo; Cassano, John; Cavazos, Tereza; Christensen, Jens H.; Christensen, Ole B.; Coppola, Erika; Evans, Jason; Geyer, Beate; Giorgi, Filippo; Hadjinicolaou, Panos; Jacob, Daniela; Katzfey, Jack; Koenigk, Torben; Laprise, Rene; Lennard, Christopher J.; Kurnaz, Mehmet Levent; Li, Delei; Llopart, Marta; McCormick, Niall; Naumann, Gustavo; Nikulin, Grigory; Öztürk, Tuğba; Panitz, Hans-Juergen; da Rocha, Rosmeri Porfirio; Rockel, Burkhardt; Solman, Silvina A.; Syktus, Jozef; Tangang, Fredolin; Teichmann, Claas; Vautard, Robert; Vogt, Juergen V.; Winger, Katja; Zittis, George; Dosio, AlessandroTwo questions motivated this study: 1) Will meteorological droughts become more frequent and severe during the twenty-first century? 2) Given the projected global temperature rise, to what extent does the inclusion of temperature (in addition to precipitation) in drought indicators play a role in future meteorological droughts? To answer, we analyzed the changes in drought frequency, severity, and historically undocumented extreme droughts over 1981–2100, using the standardized precipitation index (SPI; including precipitation only) and standardized precipitation-evapotranspiration index (SPEI; indirectly including temperature), and under two representative concentration pathways (RCP4.5 and RCP8.5). As input data, we employed 103 high-resolution (0.448) simulations from the Coordinated Regional Climate Downscaling Experiment (CORDEX), based on a combination of 16 global circulation models (GCMs) and 20 regional circulation models (RCMs). This is the first study on global drought projections including RCMs based on such a large ensemble of RCMs. Based on precipitation only,;15% of the global land is likely to experience more frequent and severe droughts during 2071–2100 versus 1981–2010 for both scenarios. This increase is larger (;47% under RCP4.5,;49% under RCP8.5) when precipitation and temperature are used. Both SPI and SPEI project more frequent and severe droughts, especially under RCP8.5, over southern South America, the Mediterranean region, southern Africa, southeastern China, Japan, and southern Australia. A decrease in drought is projected for high latitudes in Northern Hemisphere and Southeast Asia. If temperature is included, drought characteristics are projected to increase over North America, Amazonia, central Europe and Asia, the Horn of Africa, India, and central Australia; if only precipitation is considered, they are found to decrease over those areas.
