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This paper analyses the temporal and spatial changes in the amount and variability of rainfall in Scotland. The sequential Mann-Kendall test reveals that total annual precipitation has increased across Scotland since the 1970s with increasing trends in variability beginning between the mid-1960s and the mid-1970s. Whilst temporally consistent increasing trends in precipitation totals prevail in the West, many weather stations in the East have experienced subsequent trend turning points in the following two decades, explaining the larger magnitude of the trends in western Scotland in recent decades. Trend analyses on six measures of rainfall variability indicate an increase in rainfall variability during the period 1961-2000, as measured by the intra-annual variance, the winter to summer precipitation ratio and the annual cumulative sum range, with decreasing trends observed in the number of dry days. Periodicities associated with the North Atlantic Oscillation and the Atlantic Multidecadal Oscillation could explain the observed temporal variability of rainfall. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this research is to analyse temporal changes in historic rainfall variability across Scotland using different measures of variability. The CUSUM and sequential Mann-Kendall test applied to records from 28 weather stations with up to 80 years of daily precipitation data reveal the occurrence of abrupt changes in the rainfall trends. Most weather stations show a turning point between 1978 and 1985, although some stations situated in Eastern Scotland have more than one turning point. The temporal changes in rainfall variability across Scotland are presented using a number of measures of variability. [Copyright &y& Elsevier]