*Mehmet Baris Kelebek1, Fulden Batibeniz2, Baris Onol1
(1.Istanbul Technical University, Meteorological Engineering Department, 2.Institute for Atmospheric and Climate Science, ETH Zurich)
Keywords:climate change indices, combined extremes, Turkey
Recent changes in climate extremes have destructive consequences on the human environment and are expected to increase in the future. A common approach to detect the change in the extremes is the use of climate change indices. However, despite the usefulness of the indices in single type events (e.g., extreme precipitation, drought), they do not provide holistic information about combined extremes. Modified Climate Extremes Index (mCEI) is a tool that gives combined spatiotemporal information about warm and cold extremes, extreme precipitation, and extreme drought based on ten different climate change indicators. It measures the annual intensities of the combined extremes and provides information for their spatial extent. Recently, Kelebek et al. (2021) calculated mCEI over the Europe-Mediterranean region using reanalyses and highlighted the intensification of combined extremes over urbanized locations. In this study, we calculated mCEI to determine city-scale changes in the climate extremes over Turkey using the high-resolution ERA5 reanalyses and Multi-Source Weighted-Ensemble Precipitation (MSWEP) observations between 1979-2016. Results show that warm extremes are on the rise across Turkey. On the other hand, the daytime cold extremes decrease in 35 of 81 cities while the nighttime cold extremes do not change significantly. The most significant increase is in the extreme drought is over Central Anatolia whereas the moisture surplus has an increasing signal over the Aegean Region. Changes in extreme precipitation have regional inhomogeneities. The annual intensity of the combined extremes (mCEI) is between 30.97% and 45.63%, becomes maximum in 2008, and increases at a rate of 1.61 %/decade over Turkey. The climatological mean of mCEI is maximum over the Aegean cities exceeding 35%, and mCEI rises at a rate of about 4 %/decade over the same region. Although there is a decreasing signal of the combined extremes over Eastern Anatolia cities, the results are not significant. The findings of this study support previous studies focusing on climate extremes over Mediterranean climate hot-spot countries.
References
Kelebek M.B., Batibeniz F, Önol B. Exposure Assessment of Climate Extremes over the Europe–Mediterranean Region. Atmosphere. 2021; 12(5):633. https://doi.org/10.3390/atmos12050633