Scientific knowledge of future climate in contrast to data sets for applications

It is useful to distinguish between two broad types of projection information; scientific knowledge about the range of plausible climate change and datasets for use in applications.

The Cluster reports, Chapters 7 and 8 of the Technical Report and the Regional Climate Change Explorer of the website include qualitative statements as well as some quantitative ranges of change, with confidence levels, about projected climate change. This represents scientific knowledge of future climate, and is illustrated in the figure by the path on the left.

The path on the right of the figure, datasets for applications, represents the technical future climate datasets designed to meet data input requirements of quantitative impact assessment (described further in Chapter 9 of the Technical Report, and available on the website through the Map Explorer ).

Schematic of how climate model output contributes to knowledge of plausible regional change and data sets for applications

The scientific knowledge product can potentially synthesise a broader range of relevant evidence than the application datasets product and readily convey confidence and uncertainty, but is in a form that restricts its application to situations requiring more generalised climate change information.

The application-ready datasets product is usually designed to assist users in undertaking quantitative impact assessment. It draws on similar material to the scientific knowledge product, but is restricted to modelling techniques and approaches that produce projection datasets in a form suitable for use in applications. Typically this results in only a subset of the ranges of plausible future climate change being considered. A subset may be required if users require downscaled climate data (available from limited models) or if a small number of multivariate scenarios are required (best served by single climate models).

Thus application-ready datasets do not always represent the full range of changes provided by global climate models. As such, a key challenge is to ensure that application-ready data used in impact assessment are as representative as possible of current knowledge of climate change (described by the yellow arrow in figure). The Climate Futures web tool assists with the development of representative application ready data sets.