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High-resolution multi-proxy analyses of a sediment core section from Lake Jeserzersee (Saissersee) in the piedmont lobe of the Wü rmian Drau glacier (Carinthia, Austria) reveal pronounced climatic oscillations during the early late glacial (ca. 18.5-16.0k cal a BP). Diatom-inferred epilimnetic summer water temperatures show a close correspondence with temperature reconstructions from the adjacent Lake Längsee record and, on a hemispheric scale, with fluctuations of ice-rafted debris in the North Atlantic. This suggests that North Atlantic climate triggered summer climate variability in the Alps during the early late glacial. The expansion of pine (mainly dwarf pine) between ca. 18.5 and 18.1k cal a BP indicates warming during the so-called 'Längsee oscillation'. The subsequent stepwise climate deterioration between ca. 18.1 and 17.6k cal a BP culminated in a tripartite cold period between ca. 17.6 and 16.9k cal a BP with diatom-inferred summer water temperatures 8.5-10 8C below modern values and a shift from wet to dry conditions. This period probably coincides with a major Alpine glacier advance termed the Gschnitz stadial. A warmer interval between ca. 16.9 and 16.4k cal a BP separates this cold phase from a second, shorter and less pronounced cold phase between ca. 16.4 and 16.0k cal a BP, which is thought to correlate with the Clavadel/Senders glacier advance in the Alps. The following temperature increase, coupled with wet (probably snow-rich) conditions, caused the expansion of birch during the transition period to the late glacial interstadial.

Abstract. Responsiveness of Lepidoptera phenology to climate has been detected in a number of species during the current trend in global warming. There is still a question of whether climate signals would be evident in historical data. In this paper we examine the climatic response of 155 species of moths and butterflies collected during the period 1866-1884 in Wiltshire, southern England. In general, species responded to increased temperature in the previous October by delayed appearance and to increased temperature in the current spring by advanced appearance. Thus, differential changes in temperatures of the autumn and spring could well affect changes in the relative pattern of the phenology of species. Attributes influencing the species' ecology were examined to see if they influenced temperature responsiveness. In general, few consistent effects emerged, though responsiveness to climate was found to be greater for species eclosing later in the year, specifically to the previous autumn temperatures, and to hibernal environment, increasingly for species less exposed to air temperatures. These findings warn against expecting simple responses to climate warming.

In this paper we examine the bias towards weekend recording (the weekend effect) in volunteer phenology, using over 14,000 bird migration phenological observations from eight locations in the UK as a data source. Data from 45 bird species were used. Overall, 44% of all records were taken at weekends in contrast to the 28.6% (i.e. two out of seven days) that would be expected if records were evenly spread throughout the week. Whilst there is documented evidence of environmental differences at weekends, particularly in large urban areas, we believe the weekend effect is mostly a consequence of greater recorder effort at weekends. Some birds, likely to be obvious by their behaviour or abundance, had fewer weekend records than the remaining species. The weekend effect, to some extent, differed between locations and between seasons. There was some evidence that, particularly in autumn, the weekend bias may be lessening. If so, this will increase the accuracy of phenological records, making the detection of changes and responses to temperature easier.

We took daily near-surface air temperature data from across Europe to calculate a series of 12 biologically relevant temperature summaries. Mean values for two 30 yr periods, 1941-1970 and 1971-2000, were compared and rates of change calculated for those meteorological stations with sufficient data. We generated contour maps for these temperature summaries for both 30 yr periods and for the difference between them; we believe these are the first such maps for over a century. Change was most pronounced and most consistent in those variables describing the onset of spring.

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