Temperature related variables

24-hour maximum temperature

 
 

Figure 5 - The average 24-hour maximum temperature (in °C) each year for Scottish regions, from 1914 to 2004, with smoothed curves to show a running average. The vertical dashed line marks 1961.

Table 3 - The changes in average 24-hour maximum temperature (in °C) between 1914 and 2004, and between 1961 and 2004. Values in bold show that we are 95% confident (statistically) that the change is part of a measurable trend.

 

1914 to 2004 1961 to 2004
North Scotland East Scotland West Scotland Scotland North Scotland East Scotland West Scotland Scotland
Spring 0.70 0.71 0.48 0.64 1.16 1.41 1.35 1.29
Summer 0.58 0.37 0.20 0.40 1.11 1.14 1.12 1.12
Autumn 0.58 0.66 0.46 0.57 0.85 0.83 0.83 0.84
Winter 0.41 0.58 0.42 0.47 1.16 1.51 1.47 1.36
Annual 0.59 0.60 0.41 0.54 1.14 1.29 1.25 1.21

 

Regional trends

 

  • In the 1961 to 2004 period every change is part of a trend of increasing maximum temperatures.
  • But for the 90-year record, while we can see a trend in the average annual figures, it happens less frequently in the seasonal averages (only spring in North and East Scotland and autumn in East Scotland).
  • The maximum temperatures in North Scotland have increased at a faster rate than average temperatures since 1914.
  • Since 1961 increases in the maximum temperature have consistently been greater than the increases in average temperature in all regions.

Spatial trends

 

  • The greatest rises in temperature have taken place in the winter rather than summer season, particularly in southern Scotland.
  • Winter patterns of change are similar to that of the average temperature
  • The rise in daily maximum temperatures in summer has been relatively steady across the country except for the Shetland Islands, which have become cooler.

Future trends

 

  • Maximum temperatures are expected to increase in all seasons.
  • A maximum temperature that currently happens once in 10 years around Inverness may be 6ºC warmer by the 2080s.
  • The analysis in the UKCIP02 report suggests that the range of possible increases is smallest in winter and greatest in autumn.

Figure 6 - Pattern of change for average 24-hour maximum temperature (in ºC) for summer and winter, from 1961 to 2004.