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CDF data

Cumulative Distribution Function (CDF) data is one way that UKCP09 climate projection data is presented. CDF data show projections of future climate change associated with a given probability level.

In detail

Many of the image outputs provided by UKCP09 are produced using cumulative distribution function (CDF) data, including Cumulative Distribution Function plots.

CDF data provide the projected amount of climate change (relative to the baseline climate), for a particular climate variable, spatial locationtime periodemissions scenario and probability level.

Find out more


  • More information about Cumulative Distribution Functions is given in Annex 4.1 of the UKCP09 Climate change projections report.
  • An overview of how probabilistic projections are created and presented in UKCP09 is described in Box 3 of the UKCP09 Briefing report. More details are provided in Chapter 3 of the UKCP09 Climate Change Projections report, including an overview of the methodology and a discussion about the interpretation of UKCP09 probabilistic projections (see section 3.3) .
  • A discussion of sources of uncertainty in the UKCP09 probabilistic projections is available in Annex 2.4 of the Climate change projections report.