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Assessing the implications of paleoclimatic and paleoenvironmental data at temporal and spatial scales that would have directly intersected with human decision-making and activity is a fundamental archaeological challenge. This paper addresses this challenge by presenting a spatial and temporal downscaling method that can provide quantitative high-spatio-temporal-resolution estimates of the local consequences of climatic change. Using a case study in Provence (France) we demonstrate that a centennial-scale Mediterranean-wide model of Holocene climate, in conjunction with modern geospatial and climate data, can be used to generate explicit and solidly-grounded monthly estimates of temperature, precipitation, and cloudiness at landscape scales and with annual resolution, enabling consideration of climate variability at human scales and meeting the data requirements of socioecological models focused on human activity. While the results are not reconstructions – that is, particular values are single realizations, consistent with the coarse-grained data but not individually empirically derived nor unique solutions – they provide a more suitable basis for assessing the human consequences of climate change than can coarse-grained data. [ABSTRACT FROM AUTHOR]

Climate change shifts the distributions of a set of climatic variables, including temperature, precipitation, humidity, wind speed, sunshine duration, and evaporation. This paper explores the importance of those additional climatic variables other than temperature and precipitation. Using the county-level agricultural data from 1980 to 2010 in China, we find that those additional climatic variables, especially humidity and wind speed, are critical for crop growth. Therefore, omitting those variables is likely to bias the predicted impacts of climate change on crop yields. In particular, omitting humidity tends to overpredict the cost of climate change on crop yields, while ignoring wind speed is likely to underpredict the effect. Our preferred specification indicates that climate change is likely to decrease the yields of rice, wheat, and corn in China by 36.25%, 18.26%, and 45.10%, respectively, by the end of this century. [ABSTRACT FROM AUTHOR]

The paper discusses various aspects of local and regional storminess, as well as challenges in quantifying its tendencies in the eastern section of the Baltic Sea. The study is based on various long-term data sets, such as wind and sea level observation data from coastal stations and tide gauges of Estonia (1899–2013). It also discusses long-term wave hindcasts (1966–2013), reconstructions of shoreline changes, as well as the limitations and possible shortcomings in each of the data sets. Mostly located on the westerly exposed and windward coast of the semi-enclosed Baltic Sea, the case study area is sensitive to wind and storm climate changes. Different manifestations of storminess delivered somewhat specific results. When analyzed together, the first principal component of storminess was connected to the intensity of regional cyclonic activity along the polar front and had relatively high stages in 1920s–1940s, 1980s–1990s and probably also from 2010. The second component carried a local and more random imprint. Appearing independently of the high NAO or general “storminess” phases, the most notable event-driven extremes in the record were related to this component. Based on our data, we cannot confirm the existence of any general increasing long-term trends for storminess. Wherever the increase exists, it has occurred as a winter-time increase accompanied by the shift of the stormy season from autumn to winter. The spatially contrasting results for westerly and northerly exposed coasts reflect the corresponding variations in local wind, which are connected to the changes in storm track activity above northern Europe and a poleward shift of cyclones' trajectories. [ABSTRACT FROM AUTHOR]

Abstract: Palaeoenvironmental and palaeoclimatic data indicate that during the mid-to-late Holocene eastern Australia became significantly drier and experienced more intense and more frequent droughts. These changes, driven by the re-emergence and intensification of the ENSO climate phenomena, have been argued to have had considerable impact on Aboriginal societies, although there is uncertainty as to the exact nature, timing and magnitude of this impact. This paper analyses changes in the utilisation of toxic Macrozamia (cycad) seeds at seven archaeological sites in eastern Australia, identifying an extremely close correlation between the intensity of seed use and two proxy ENSO datasets, and a weaker correlation with a third ENSO dataset. Given the ecological attributes and resource potential of these plants, it is argued that these correlations are best explained as an intensified exploitation of a lower-ranked resource in direct response to the increased subsistence risks and lower productivity created by ENSO-driven climatic conditions. It also suggests that by 3000 BP the intensification of the ENSO system was driving changes in human subsistence behaviour on a sufficient scale to have considerable impact on other aspects of the wider cultural systems. [Copyright &y& Elsevier]

Abstract: Drought severity is conventionally assessed by drought indices. Several drought indices with varying complexity have been used in many geographical areas. Recently, a powerful drought index, the Reconnaissance Drought Index (RDI), is gaining wide acceptance mainly in the arid and semiarid climatic regions. Since RDI is based both on precipitation and potential evapotranspiration (PET), it is interesting to assess the effect of the PET calculation method on the drought severity characterisation obtained by RDI. This paper compares the results of RDI for various reference periods using some popular empirical PET methods with minimum data requirements. The selected methods are: Hargreaves, Thornthwaite, Blaney–Criddle and FAO Penman–Monteith (only temperature). The FAO Penman–Monteith method is used as reference method. The data used are from meteorological stations in Greece representing the mountainous and the coastal Mediterranean climatic conditions. No significant influence on RDI was detected by using the selected PET methods. However, the Hargreaves and FAO P–M (only T) methods performed relatively better. This supports the opinion that RDI is a robust drought index, not dependent upon the PET calculation method. [Copyright &y& Elsevier]