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A 236-year time series of monthly areal average precipitation for Scotland is produced using the 'official' record compiled by the Meteorological Office (UKMO) from 1869 onwards, corrected for known inhomogeneities, and extended back to 1757 using previously unpublished data from the UKMO. The complete series is evaluated and examined for fluctuations and extreme values with particular reference to observed precipitation increases over the last two decades. Recent increases in annual precipitation, and associated seasonal variations, are judged to be unusual despite the recognition of a longer term trend to higher annual and winter values. Correlations of precipitation since 1869 with Lamb weather types show differences within the record and from other work, which suggest that this index does not fully capture the synoptic conditions relevant to precipitation over Scotland as a whole. The series since 1869 was also used to test the predictive value of climatic normals for 3, 5, 10, 15, 20, and 25 years alongside the standard 30-year averages of precipitation. It is suggested that the best estimate of seasonal and annual precipitation totals for the following year can be achieved by the application of 3-and 5-year normals, rather than by using precipitation averages of longer duration.

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This paper examines the relationships between river water temperature, air temperature and stream flow measured continuously for one year at four sites along the main stream of the river Tees in northern England. Maximum and minimum river temperatures were found to correlate fairly closely with equivalent air temperatures at each site, but some emphasis was placed on the effects of hydrological factors on water temperature variations within the 818 km2 basin. The range of water temperature fluctuations was shown to increase upstream and the highest river maxima were also recorded in the upper reaches of the river, owing to the relatively low volume of discharge. On a shorter time scale, stream flow was also found to exert an important influence on river temperature during snowmelt and peak flow events arising from storm rainfall. A multiple regression analysis indicated that air temperature and stream flow together accounted for up to 85 % of the variation of daily maximum and minimum river temperatures in summer.

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