Suchergebnisse

Prompted by Wyndham Lewis's call in BLAST for a 'USEFUL LITTLE CHEMIST' to 'restore to us the necessary BLIZZARDS', this paper considers the conceptions of climate and climatic change – natural and anthropogenic – that were in circulation in the early twentieth century. Engaging with the writing of scientists, journalists, novelists, and avant-garde polemicists, it examines early twentieth-century iterations of the notion that climate determines culture, the period's awareness of past climatic changes, the theories advanced to explain these changes, and the attitudes taken towards the possibility of human-induced climatic change.

The koala (Phascolarctos cinereus) occupies a broad range of eastern and southern Australia, extending over tropical coastal, semiarid inland and temperate regions. In many areas koala populations are under threat, in particular from the direct and indirect effects of ongoing habitat destruction due to increased urbanisation and other anthropogenic processes. Climate change presents additional threats to the integrity of koala habitats because many species of food and non-food trees have narrow climate envelopes and are unable to adapt to altered temperatures and rainfall. Climate extremes also produce physiological stresses in koalas that may increase the likelihood of outbreaks of chlamydiosis and other diseases. Climate change–related increases in the relative content of toxic chemicals in leaves are further stresses to the koala after ingestion. In addition, populations that originated from a small number of founder individuals are at potential risk due to their relatively low genetic diversity. Strategies that maintain residual habitat fragments and promote the construction of new refugia are now being formulated. Modelling of the impact of habitat metrics on koala distribution is providing important information that can be used in the rehabilitation of koala refugia. In future these models could be augmented with metrics that describe koala homeostasis to inform local conservation strategies. These considerations are also relevant for the maintenance of other taxa in the wider ecosystem that are also at risk from habitat destruction and climate change.

Abstract
The study is based upon instrumental observations of ice covers which formed on the lakes in northern Poland in the period 1956-2005 and records of air temperature measured at 9 meteorological stations in the period 1960-2005. Relations between mean dates of ice cover freeze-up, ice cover duration, maximum ice thickness, and also other properties of ice regime indicate obvious dependency upon air temperatures in winter months (December-February). Both air temperatures and main properties of ice covers revealed definite trends, showing the increase in air temperature in winter (0.04-0.06°C year-1), earlier disappearance of ice cover (0.5-0.6 day year-1), its shorter duration (0.6-0.7 day year-1), and decreases in maximum thickness of the ice cover (0.2-0.25 cm year-1). The author shows considerable statistical relations between main properties of the course of the ice cover, air temperatures in winter and the NAO winter indexes. Therefore, changeability of the ice covers on the lakes in northern Poland in the latter half of the twentieth century may be treated as another proof and an indirect indicator of climatic changes undergoing in this part of Europe.