What does the DDC provide?
Data collections
The DDC provides four main types of data and guidance, which meet certain criteria laid down by the TGICA. They are introduced briefly here and described in more detail throughout the web site and accompanying guidelines:
1. Observed Climate Data Sets
The climate observations comprise 1961-1990 mean monthly data over global land areas for nine variables on a 0.5º latitude/longitude grid, together with decadal anomalies from this mean for the period 1901-1995. This data set is currently being updated to 2000 and interpolated to a finer resolution (10 x 10 arc minutes). Pointers are provided to other relevant global climatologies.2. Global Climate Model Data
Global climate model data is available as monthly means or as climatologies. Data is held for climate model projections used as input to the Second, Third and Fourth IPCC Assessment Reports. Full details of the variables held can be found on the relevant data pages. The climatologies aof climate model projections can also be viewed through the DDC visualisation service.Daily fields are not provided by the DDC, but are available from PCMDI or from the respective modelling centres.
3. Socio-economic data and scenarios
Socio-economic data and scenarios are required for describing socioeconomic development and adaptation capacity. The reference data include country and regional level indicators of socio-economic and resource variables. The scenario data supplied extend to 2100 and are based on the assumptions underlying the new set of emissions scenarios developed for the IPCC Special Report on Emissions Scenarios, SRES, as well as the six IS92 emissions scenarios prepared by the IPCC in 1992. There is also detailed guidance on the use of DDC data to develop socio-economic and adaptation scenarios as well as links to related guidance material developed by other agencies.4. Data and scenarios for other environmental changes
Some data and information for other environmental changes is also included in the site. These include data on global mean CO2 concentration, global and regional sea-level rise, regional ground-level ozone concentration, sulphate aerosol concentration and sulphur deposition. All of these scenarios were developed for the IPCC Third Assessment Report based on the SRES emissions scenarios. Detailed documentation and guidance is also provided for the use of these data.User support
- More information about the guidelines can be found here.
- There is a "Frequently Asked Questions" page.
- Results of a user survey conducted in April/May 2009 can be read here.
