What to be aware of
There are a number of issues that you should be aware of in relation to the climate observation grids available from the Met Office website , trend information from UKCP09 and climate observations in general.
1. Observed daily precipitation data is only available under a separate Met Office licence agreement for which charges may apply.
Those wishing to have access to the daily precipitation datasets should enquire at the Met Office . For UKCP09 users, the Met Office has made available various derived quantities calculated for each 5 km grid, by year and season; see the Met Office website . These derived quantities are provided to help comparisons with the UKCP09 Weather Generator baseline values.
2. No sub-daily climate information is available
The available datasets do not include observations at less than daily time-steps. As such, there are no observational data available through UKCP09, which can be compared with the baseline (1961-1990) hourly values generated by the UKCP09 Weather Generator.
3. The observed climate during this period has been changing
The climate during the period of record has been changing (see below), and is therefore non-stationary. You should exercise caution when calculating and interpreting return periods and other statistics that assume a stationary data set.
4. Trends information is available from this site in the form of map images, graphs and summary tables
Information on changes and trends in key climate variables were calculated based on data available at time of publication of UKCP09 which spanned the period 1914 to 2006 for temperature and precipitation and 1961 to 2006 for other variables. In some instances more recent years (for example the wet summers of 2007 - 2012) could have significantly changed some of these trend estimates. The UK climate pages on the Met Office website provide routine climate monitoring data and statistics that could be used to check this at a national scale. Summary information for UKCP09 is provided in three different ways:
1) Maps: These include maps illustrating the difference between two 30-year periods (1961-1990 and 1971-2000), and maps showing changes over the period 1961-2006. These are available in the Observed trends report images section.
2) Graphs: Graphs of trends are also included for the 14 UKCP09 administrative regions. These are also available in the Observed trends report images section.
3) Tables: Tables of change over the period 1961-2006 by season and for the whole year are also provided for each of the 14 UKCP09 administrative regions. In addition, changes for temperature and precipitation are given for the period 1914-2006. These tables can be found in the key findings spreadsheet that can be downloaded from the maps and key findings selector.
Users are encouraged to refer to the full UKCP09 Observed trends report to view the maps, graphs and tables, and details of how the results were calculated.