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Time period

In UKCP09 a 'time period' refers to a 30-year period over which climate averages are calculated.

In detail

UKCP09 uses 30-year time periods for both the baseline climate and for all future climate projections. The projections are reported for seven overlapping 30-year time periods. Each future time period is referred to by the middle decade (for instance the 30 year time period from 2040 to 2069 is usually referred to as the '2050s').

The UKCP09 time periods are:

  • 1961 to 1990 - the baseline period 
  • 2010 to 2039 - the 2020s;
  • 2020 to 2049 - the 2030s;
  • 2030 to 2059 - the 2040s;
  • 2040 to 2069 - the 2050s;
  • 2050 to 2079 - the 2060s;
  • 2060 to 2089 - the 2070s;
  • 2070 to 2099 - the 2080s

Find out more

  • The time periods are shown graphically in Figure 1.3 of the UKCP09 Climate change projections report.
  • More details about the baseline climate of the UK, including regional differences, are given in the maps and guidance section of the Observed Trends report..
  • The implications of one's choice of time period are discussed in section 4.4 of the UKCP09 Climate change projections report.