In this contribution air temperature differences among Local Climate Zone (LCZ) categories are analysed with special consideration of varying synoptic conditions. Analyses are based upon an LCZ mapping for the urban area of Augsburg (Bavaria, Southern Germany) and hourly air temperature data from a comprehensive logger network. Quality checked air temperature measurements have been stratified according to season, hour of the day and weather situation. For resulting subsamples thermal differences among LCZs have been determined and appropriate statistical tests have been applied. Results confirm that built up LCZs feature higher temperatures than natural LCZs and that most distinct differences among LCZs appear under undisturbed synoptic conditions. With increasing cloudiness and in particular with increasing wind speed differences among LCZs diminish. But, even for strongly disturbed synoptic conditions statistical significance of the influence of LCZs on thermal characteristics could be assured. Thus, our findings provide clear evidence that detectable thermal differences among LCZs are not restricted to "ideal" synoptic conditions but occur as well under disturbed conditions. However, to assure not only the statistical but also the climatological and in particular the bioclimatological and human health related relevance of the documented differences among LCZs further studies incorporating appropriate metrics are intended. Keywords urban climate, local climate zones, urban air temperature, urban meteorological network, urban heat island

There is increasing concern that precipitation and temperature extremes may be changing in frequency and character as a result of changing climate, and the latter is mostly linked with particular changes in the atmospheric circulation. Therefore the question arises-a key question in the climate change prospective-as to how precipitation and temperature extremes are related to large-scale atmospheric circulation types? To study such relationships over an extended period of more than one and a half centuries, we include daily precipitation and temperature time series compiled during the EU project EMULATE (European and North Atlantic daily to multidecadal climate variability) back to 1850 as well as daily mean SLP reconstructions from the same project for the same period. The latter data set has been used for classifying daily circulation types for each season using a simulated annealing clustering technique. Comparing each of these circulation types with their percentages among extreme days and among non-extreme days (with respect to precipitation or temperature) clearly reveals that in most cases only a few of the seasonal circulation types are conducive to the occurrence of daily extremes. This is shown for heavy precipitation and positive temperature extremes (beyond the 98th percentile in each case), related to the winter (DJF) and summer (JJA) seasons for a central European region. Different circulation patterns proved to be important in this context. Thus, in contrast to positive temperature extremes during winter being linked preferably to zonal circulation patterns (positive mode of the North Atlantic Oscillation, NAO), heavy winter precipitation in central Europe is distinctly associated with less zonal patterns characterized by an eastward or southeastward shift of the subpolar centre of low pressure implying only weak correlations with the NAO. Furthermore, particular indices reveal that changing frequencies of extremes are not only due to corresponding frequency changes of these conducive circulation types, but also to changes of their association to precipitation or temperature extremes (ref ected by changes in the percentage of extremes related to the overall occurrence of the corresponding circulation type). These within-type changes of circulation types often govern the low-frequency variations in the overall incidence of extremes.

Variability of sea surface temperatures (SSTs) in the tropical southeast Atlantic Ocean has previously been shown to significantly contribute to changes in summer rainfall along the West African as well as the Angolan coast. This study examines links between southeast Atlantic SST and African west coast precipitation variability for an extended 60-year period from 1951 to 2010. In contrast to earlier studies, our analyses cover the whole Atlantic coast from Guinea to South Africa and are not limited to specific seasons. In addition to the analyses of the total variability, pronounced anomalies in terms of warm and cold water events and their impact on African west coast precipitation are analyzed. By using for the first time a new comprehensive classification of Atlantic Niño and Niña events, consistent results are achieved for a larger region of Africa, also considering Atlantic cold water events which have rather been neglected so far.Results show that, depending on the particular region, southeast Atlantic SSTs play an important role for coastal rainfall variability throughout the year. Furthermore, the rainfall response to Atlantic cold and warm water events appears to be asymmetric in season and magnitude. Atlantic cold events can cause a stronger decrease in rainfall along the West African and Gabon coast than the increase is in warm events. In addition, not all seasons show a significant rainfall response to both warm and cold water events.

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This study investigates visitors' perceptions and preferences regarding the characteristics of deadwood in the Bavarian Forest National Park (SE-Germany). Visitor-employed photography has been used to collect information about visitors' preferences. Deadwood is the second most photographed forest element which underlines its important role in forest perception. Even though deadwood photographs are evaluated significantly worse than most other forest elements, most visitors nevertheless associate deadwood photographs with a positively rated forest image. Based on the relationship between aesthetics and recreation revealed in the interviews, it can be concluded that the forest path during the hike was both pleasant and restful. This is confirmed by the post-trip interviews, showing that a higher proportion of deadwood is associated with more aesthetics or recreational value. Regarding deadwood structure results show that deadwood fragments and debris are perceived negatively, while root stocks were assessed more positively. We also found a gradient with positive evaluations increasing with progressing decomposition.