- If you are new to using climate change information, go to www.ukcip.org.uk
It is important to understand your vulnerability to the current climate before you look to the future. UKCIP have a number of tools to help you:
- UKCIP's Essentials pages (external website)
- UKCIP Adaptation Wizard (external website)
- UKCIP's Risk, uncertainty & decision-making framework (external website)
- Business Areas Climate Assessment Tool (BACLIAT) (external website)
- Local Climate Impacts Profile (LCLIP) (external website)
- UKCIP’s introduction to UKCP09 (external website)
- What is UKCP09 section
- UKCP09 provides future climate projections for land and marine regions, and observed climate data.
- There are key findings and maps
- In-depth reports are available online or to download:
- UKCP09 provides projections (possible), not predictions (probable)
UKCP09 offers projections of the future climate that is based on the current understanding of the climate system – there may be scientific unknowns that would affect the information provided. Hence UKCP09 should be seen as providing possible projections rather than absolute predictions or forecasts of future climate.
- UKCP09 is based on cutting-edge science, and is designed for a wide variety of users
UKCP09 are the first UK climate projections to be probabilistic in nature, and incorporate data from an ensemble of climate models. See What is UKCP09? for more information.
- Probabilistic information is challenging – but there's guidance, training & courses to help
UKCP09 is supported by online guidance:
- Reports & guidance section
- Case studies to help anyone who needs to use UKCP09
- Training and online courses
- FAQs on a wide range of subjects
- The Index will help to find what you are looking for
- UKCP09 Helpdesk
Unlike previous climate information, UKCP09 provides a range of possible outcomes rather than a single number or percentage. Decision-makers should consider the 10–90% range across the emissions scenarios. Selecting, for example, a single probability level and a single emission scenario would omit a wide range of possible outcomes which would affect the robustness of any decision made.
- UKCP09 is one of many tools available, don't use it in isolation
Users will need to assess their project's vulnerability to climate change, along with the impacts and risks of a changing climate, and identify potential adaptation plans. For further guidance on undertaking such assessments, go to the UKCIP website, for example the Adaptation Wizard and Risk management framework .
- Maps are best for communicating messages, not making decisions
Maps produced using UKCP09 are useful visual aids but, because of the probabilistic nature of the information, do not present a snapshot of future weather, and users should take care not to interpret them as such. See the Inappropriate uses section for more guidance on interpreting and using UKCP09 maps.
- Projections in the 10–90% probability level range are more robust
Analysis of the results of UKCP09 indicates that very high or very low probability levels (known as the tails of the distribution, e.g. 95% probability level) are not as as results within the 10–90% probability level range. For this reason anything outside of the 10–90% probability level range can be taken into account, but may not be considered robust in decision-making.
- To compare or combine climate variables, you will need to use the sampled data
The data set used to generate the maps and graphs is a single variable dataset which means the results for two or more climate variables should not be used together, e.g. not combined to say the climate is wet and cool. Mapped results for two or more variables should also not be overlaid on a GIS map. See guidance on CDF data. This does not apply to the joint probability plots, which use the sampled data; sampled data should be used for any multi-variable analysis.
- Not ALL potential futures are modelled
To make projections of future possible climates, assumptions had to be made about levels of future emissions of greenhouse gases. A number of emissions scenarios were developed by the IPCC (SRES) which reflect changes in the way economies are structured, population grows, technology develops, as well as energy intensity and land use changes. For UKCP09, three different emissions scenarios were used that span the full range of SRES scenarios, known as Low, Medium and High. None of these includes a scenario where action is taken to drastically reduce greenhouse gas emissions (known as a stabilisation scenario). For more information see Annex 1 of the Climate change projections report.
- Finer modelling resolution does not give greater confidence
The process of downscaling, where data from a large spatial scale model is reduced to smaller, more local scale, increases the uncertainty of the outcome.
- See this FAQ on uncertainty
- For an explanation of why , see this FAQ
The UKCP09 Weather Generator, although at 5 km resolution, does not contain any more climate change information than is available in the 25 km projections because the future sequences of climate are generated from the 25 km projections (). The 5 km grid does contain more topographical detail, which may be important for some users.
- Changes to the Gulf Stream are taken into account, as are carbon feedbacks & aerosols
Some recent studies have shown a reduction in the strength of the Meridional Overturning Circulation in the North Atlantic (MOC), sometimes called the Gulf Stream circulation. The effects of a gradually weakening MOC are included in the UKCP09 projections. See Annex 5 of the Climate change projections report for more information.
Carbon feedbacks and aerosols have also been taken into account in UKCP09.
- Confidence levels vary depending on the climate variable and time period
Our limited understanding of the climate system and the limits of our ability to model that system mean that, for example, there is relatively high confidence in projections of some variables, e.g. temperature, and relatively less confidence in others, e.g. precipitation (summer precipitation, particularly), and cloudiness.
- UKCP09 does not have projections for snow
It was not possible to develop probabilistic projections of future changes in snow in UKCP09. For more detail, see the Climate change projections report Section 4.8.