[1] A new data set of high-quality homogenized daily maximum and minimum summer air temperature series from 246 stations in the eastern Mediterranean region (including

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During the period of instrumental records, the North Atlantic Oscillation (NAO) has strongly influenced interannual precipitation variations in the western Mediterranean, while some eastern parts of the basin have shown an anti-phase relationship in precipitation and atmospheric pressure. Here we explore how the NAO and other atmospheric circulation modes operated over the longer timescales of the Medieval Climate Anomaly (MCA) and Little Ice Age (LIA). High-resolution palaeolimnological evidence from opposite ends of the Mediterranean basin, supplemented by other palaeoclimate data, is used to track shifts in regional hydro-climatic conditions. Multiple geochemical, sedimentological, isotopic and palaeoecological proxies from Estanya and Montcortés lakes in northeast Spain and Nar lake in central Turkey have been crosscorrelated at decadal time intervals since AD 900. These dryland lakes capture sensitively changes in precipitation/evaporation (P/E) balance by adjustments in water level and salinity, and are especially valuable for reconstructing variability over decadal-centennial timescales. Iberian lakes show lower water levels and higher salinities during the 11th to 13th centuries synchronous with the MCA and generally more humid conditions during the 'LIA' (15th-19th centuries). This pattern is also clearly evident in tree-ring records from Morocco and from marine cores in the western Mediterranean Sea. In the eastern Mediterranean, palaeoclimatic records from Turkey, Greece and the Levant show generally drier hydro-climatic conditions during the LIA and a wetter phase during the MCA. This implies that a bipolar climate see-saw has operated in the Mediterranean for the last 1100 years. However, while western Mediterranean aridity appears consistent with persistent positive NAO state during the MCA, the pattern is less clear in the eastern Mediterranean. Here the strongest evidence for higher winter season precipitation during the MCA comes from central Turkey in the northeastern sector of the Mediterranean basin. This in turn implies that the LIA/MCA hydroclimatic pattern in the Mediterranean was determined by a combination of different climate modes along with major physical geographical controls, and not by NAO forcing alone, or that the character of the NAO and its teleconnections have been non-stationary.

This paper presents the spatial and temporal characteristics of Turkey's annual rainfall data in the context of climatic variability. Basic data consists of the monthly rainfall totals from 91 stations with a record length ranging from 54 to 64 years, during the period 1930–1993. Basic elements of the rainfall climatology have been examined and then normalized rainfall anomaly series have been analysed for long‐term trend and fluctuation and changes in runs of dry and wet years, for all of Turkey, rainfall regime regions, and individual stations. All regional mean rainfall anomalies have tended to vary in a statistically coherent manner over the rainfall regions. Area‐averaged annual rainfall series have decreased slightly over all of Turkey and apparently over the Black Sea and Mediterrane an rainfall regions. Results of the Mann–Kendall test, however, have indicated that none of the decreasing trends in the area‐averaged rainfall series were significant. Annual series of 17 stations showed a significant trend in the mean and a majority of these trends are downward. Many of the stations have experienced marked low‐frequency fluctuations in the annual rainfall. The concurrences of the dry conditions between the rainfall regions and the rest of Turkey have appeared generally during the early 1930s, the late 1950s, the early 1970s, around the 1980s and the early 1990s and of wet conditions generally during the period 1935–1945, around the 1960s and the late 1970s. The change points for the beginning of drier than normal conditions occurred in the early 1970s and early 1980s over most of the country. Annual rainfall variations over the rainfall regions except the Black Sea region were related closely to those of the rest of Turkey.