ABSTRACT

This chapter describes the key components of the mid-latitude circulation: air masses, depressions and anticyclones. Synoptic climatology, the study of local and regional weather in relation to these large-scale atmospheric features, has now been practised for at least a century. The task of analysing the weather and climate of the oceanic margins of north-west Europe is complicated by virtue of the region's situation at a crossroads of contrasting atmospheric and oceanic influences. Regional climate classifications of north-west Europe reflect a hierarchy of factors. Climate variability can be detected at a range of temporal scales: from apparently random, extreme precipitation events operating over hours or days, through to periodicity in temperature at the millennial scale. The relative significance of natural versus human causes of climate change has become the subject of considerable debate. The most common method of weather classification involves combining aspects of prevailing wind direction with the dynamic features of pressure charts.